Commercial Gardening

MARKET CHRYSANTHEMUMS
i. Le Peyron. 2. Freda Bedford. 3. Elsie Fulton. 4. Mrs. F. MacNeice

(Half natural size)

ffi

COMMERCIAL
GARDENING

A PRACTICAL & SCIENTIFIC TREATISE
FOR MARKET GARDENERS MARKET
GROWERS FRUIT FLOWER & VEGE-
** TABLE GROWERS NURSERYMEN ETC.

tMany 'Practical Specialists
under the Editorship of

JOHN WEATHERS

Author of "A Practical Guide to Garden Plants"
"French Market Gardening" "The Bulb Book" &c.

In Four Volumes: Fully Illustrated

VOLUME I (3D

(J! THE GRESHAM PUBLISHING COMPANY (JO
34-35 Southampton Street Strand London

~ ~ - "

PREFACE

The very title of this work at once distinguishes it from all other
treatises on Horticulture, and at the same time strikes a note indicating
its predominant features. The work is "commercial" in every sense of
the term, because it deals with gardening from the point of view of the
man who grows plants not so much for pleasure as for profit. It is also
" gardening " in the best sense of the word, as the cultural methods of the
best market growers are detailed. Commercial Gardening, indeed, is
intended as a work not only for the bookshelves, but for the hands of all
those who are engaged, or intend to become engaged, in Horticulture for
Profit, and who are desirous of growing those crops of fruits, flowers, or
vegetables likely to yield the most remunerative results.

In considering gardening from what may be called a pounds, shillings,
and pence point of view, it is essential to take note chiefly of those crops
that can be grown in the open air or under glass, and are likely to yield
a profit, large or small, upon their cultivation. It does not at all follow
that what may be justly regarded as the loveliest and most charming
flowers, the most decorative plants, or the finest-flavoured fruits or vege-
tables, are necessarily those that" will yield the handsomest profits when
cultivated on a large scale. Unfortunately the reverse is often the case,
and enormous numbers of various plants are grown, not because they
happen to be the very finest representatives of their class, but simply
because they find a more ready sale in the markets than their choicer
brethren. This is easily explained on the ground that those who grow
produce for sale, and those who buy it, belong to quite different classes of
the community. The market buyer usually is not a trained horticulturist,
and he will only invest in produce that has already made a name for itself,
and is therefore not likely to remain long on his hands. If he ventures
to invest in produce which he has never seen before, or knows but little
about, he finds that when he recommends it to his customers they leave

Preface

it severely alone evidently under the impression that he is trying to
push unduly the sale of what he considers to be a useless drug on the
market. Many excellent plants have met this fate, and it has taken years
before others have become sufficiently well-known to florists, greengrocers,
and street sellers to make their cultivation at all profitable. Sometimes,
however, a new kind or variety will jump into popular favour at once, and
the commercial gardener, who is regularly in touch with the markets and
is being constantly influenced by their atmosphere and traditions, proceeds
at once to propagate and cultivate the new favourite in sufficiently large
quantities to meet the demand. In this way some of the older favourites
are gradually displaced by the newer ones, and it is only when one comes
to compare the kinds or varieties of plants or flowers that were sold in
quantities twenty, thirty, or fifty years ago with those sold at the present
day, that one realizes what enormous changes have taken place.

Not only have new races superseded old ones, but the cultural methods
of commercial gardeners have also undergone remarkable changes. Cleaner
and more economic methods of cultivation also prevail to-day, and gar-
deners who have to make a living out of the growth of plants have in
many cases come to recognize the vast importance of the scientific aspects
of their calling. In these days the grower who would erect glasshouses
with small panes of glass and an enormous quantity of timber would be
regarded as insane. The importance of light and fresh air is now so well
understood, that the main object in view is to secure as much of each,
especially during the winter months, as is possible.

The market gardener has perhaps more to learn in this respect than
the market grower. In many instances he practises the old and erroneous
farming system of cramming and crowding his fruit trees and bushes to-
gether in such a way that in a few years they become a mass of diseased
and distorted vegetation, yielding very poor, if any, profit. It is one
of the most difficult things to make some of the old school of market
gardeners and farmers realize that the great bulk of the dry weight of
any plant fruit, flower, or vegetable is obtained from the carbon of the
atmosphere under the influence of sunlight. They simply will not believe
it because they cannot see it. It is ever present to the minda of such that
to give any plant a fair amount of space and air and light, according to
its nature, would be " wasting ground ", as they term it. The natural
corollary to this lack of knowledge is the thought that the greater the
number of plants put into a given area of ground, the larger and better

Preface

VII

the crops likely to be got out of it one of the most pernicious and
dangerous doctrines for any commercial gardener to play with.

In this work on Commercial Gardening the best and cleanest methods
of cultivation are those recommended, simply because they happen to be
the most economical. But no false economy is preached, and it may be
cheaper, even for the man with a small capital, to make a fair start by
thoroughly cultivating his ground to a depth of 3 ft., at a cost of 8 to
12 per ac., than to fritter away his substance for a lifetime and never
go deeper than six inches or a foot from the surface. The cultivator who
is now foolish enough to think that the methods employed by his ancestors
in the old non-competitive days are quite good enough for him, is making
a sad mistake in these speedy days of keen competition. The modern
grower is affected by the changes brought about by science and fashion,
and he must adjust his methods and vary his crops according to prevailing
circumstances. Perhaps it only remains to be said that the information
given in this work has been supplied by men most of whom are, or have
been, actually engaged in growing crops of various kinds for profit, and
are regarded as skilful cultivators and good business men. The Editor
takes this opportunity of thanking them for their kind assistance, and in
doing so would also like to express his indebtedness to many other com-
mercial gardeners who prefer to handle the spade rather than the pen
for many hints and much information given in regard to various matters.

Among the principal contributors the following may be mentioned, with
the initials used to mark their contributions throughout the work.

A. A. ARTHUR AMOS, Downing College, Cambridge.

A. J. B. A. J. BRIDGES, Nurseryman.

C. E. CARL ENGELMANN, Nurseryman and Carnation Specialist.

C. T. D. CHARLES T. DRUERY, President, British Fern Society.

E. H. J. E. H. JENKINS, Nurseryman and Horticultural Writer.

F. V. T. Professor F. V. THEOBALD, M.A., Zoologist to the S.E. Agricultural

College, Wye; Author of Insect and Allied Pests of Orchard, Bush,
and Hothouse Fruits.

F. W. M. Sir FREDERICK W. MOORE, M.A., F.L.S., Glasnevin.

G. G. GEORGE GORDON, V.M.H., Editor of the Gardeners' Magazine.
G. M. GEORGE MASSEE, F.L.S., &c. ; Author of Diseases of Plants.

Vlll

Preface

J. B. R. JAMES B. RIDING, Nurseryman and Horticultural Writer.

J. E. H, JOSEPH ERNEST HILL, J.P., Fern Specialist and Nurseryman.

J. F. JOHN FRASER, F.L.S., late Editor, Gardening World.

J. M. JOHN MAY, late Market Grower and Cyclamen Specialist.

J. M. H. J. M. HODGE, Blairgowrie.

J. U. JAMES UDALE, Chief Horticultural Instructor, Worcestershire County

Council.

J. W. JOHN WEATHERS, formerly a Market Grower, Author of A Practical

Guide to Garden Plants, French Market Gardening, Lecturer on
Horticulture, &c.

P. A. C. PERCY A. CRAGG, Market Grower.

W. M. B. WILFRID M. BEAR, Grape and Tomato Grower.

W. G. L. WILLIAM G. LOBJOIT, J.P., Market Gardener and Fruit Grower, Vice-
Chairman of the Market Gardeners', Farmers', and Nurserymen's
Association.

W. T. WILLIAM TRUELOVE, Nursery Propagator.

CONTENTS

VOLUME I

SECTION L GENERAL ASPECTS OF COMMERCIAL
GARDENING

Page

Introductory The Seed Trade The Bulb Trade The Hardy-plant
Trade The Nursery Trade Market Gardening and Market
Growing The Florist Trade Tree and Shrub Trade Japanese
Gardening 1

SECTION II. THE SCIENCE OF PLANT GROWING

1. SIMPLE AND COMPLEX CELL LIFE. Simple Cell Life - 20

2. STRUCTURE OF THE HIGHER PLANTS. The Growth of a Cell
Changes in Cell Walls Various Forms of Cells Plant Tissues
Uses of Different Cells - - 22

3. PLANTS OF DISTINCTIVE CHARACTER. Plants with Chlorophyll
Plants without Chlorophyll Desert Plants Clammy -leaved
Plants Insectivorous Plants Climbing Plants - 26

4. THE ROOT AND ITS WORK. The Primary Root Importance of
Primary and Fibrous Roots Relation of Soil to Roots Water
and Air Roots Tuberous Roots Work of the Roots The
Food absorbed by Roots Contractile Roots - - 29

5. THE STEM AND ITS FUNCTIONS. The Seedling Stem The Growth
and Thickening of the Stem The Cambium Dicotyledonous
and Monocotyledonous Stems Bulbs, Corms, Tubers, and
Rhizomes - - 35

6. LEAVES AND THEIR WORK. Seed Leaves and True Leaves
Structure and Contents of a Leaf Work of a Leaf Forms of
Leaves and their Clothing Arrangement of Leaves Modified
Leaves The Fall of the Leaf - - 42

7. MOVEMENTS OF WATER AND FOOD PRODUCTS IN PLANTS. Root
Pressure Water of Transpiration Transport of Food Materials
Water Plants Sap in Winter Bleeding - - 52

Contents

8. MODES OF GROWTH AND VEGETATIVE EEPRODUCTION. Mono-
podial and Sympodial Stems Forms of Inflorescence Flower
Buds and Pruning Propagation by Roots Propagation by
Stems Propagation by Leaves - 55

9. THE FLOWER AND ITS FUNCTIONS. The Parts of a Flower
Pollination and Fertilization Sexual Reproduction Cross-
breeding and Hybridization Various Forms of Fruit Seeds
Germination - - 60

SECTION III. METHODS OF PROPAGATION

Seeds Vitality of Seeds Seed Sowing Cuttings Woody Cuttings
Leaf Cuttings Ringing Root Cuttings Layering Runners
Suckers Offsets Bulbils Division of the Rootstock Bud-
ding Grafting Whip Grafting Cleft and Rind Grafting
Saddle Grafting Side Grafting Herbaceous Grafting Root
Grafting Inarching or Grafting by Approach Bottle Grafting 71

SECTION IV. THE SCIENCE OF THE SOIL

1. INTRODUCTORY - 89

2. CLASSIFICATION OF SOILS. Sand Clay Loam Chalk Lime

Peat Humus Advantages of Humus - - 91

3. MECHANICAL ANALYSIS OF SOILS - 96

4. How SOILS HAVE BEEN MADE. Water Frost Heat Wind

Vegetation - - 98

5. CULTURAL OPERATIONS. Ploughing Digging Double Digging
Trenching Ridging Up Raking and Harrowing Rolling
Hoeing - - 101

6. THE BEST TIME TO WORK THE SOIL - - 107

7. PLANT FOODS IN THE SOIL AND AIR - - 108

8. How TO EXTRACT PLANT FOODS FROM THE SOIL - 112

9. WATER IN THE SOIL. How Moisture is Lost Loss of Water
through the Leaves Movement of Water in the Soil Water
Lost by Weeds The Upward Movement of Moisture in Soils:
Capillary Attraction Conserving the Moisture in Soil: The
Use of Hoeing and Mulching - - 116

10. LIVING ORGANISMS IN THE SOIL. Nitrification Soil Inoculation

Deriitrification - - 125

11. STERILIZING SOILS. Burning and Steaming the Soil - - 130

12. ELECTRIFYING THE SOIL - - 131

13. SOIL ANALYSIS. Chemical Analysis Lime Carbonate Phos-
phates Potash Iron Calcium Carbonate Humus Magnesia 132

Contents xi

SECTION V. MANURES AND MANURING

Page

1. INTRODUCTORY. Misleading Experiments The Object of Manuring 137
2. KINDS OF MANURES - - 145

3. COMPLETE MANURES. Farmyard Manure or Dung Storing Farm-
yard Manure Value of Farmyard Manure A Warning
Green Manuring Leaves as a "Green Crop" Roots as a
Manure Guano Fish Guano Seaweed Soot Blood
Manures Night Soil and Poudrette Rape Cake and Rape
Dust Malt Dust or Kiln Dust Wool and Shoddy Hair,
Feathers, Skin, Leather Waste, Greaves - - 146

4. NITROGENOUS MANURES. Nitrate of Lime Nitrate of Soda or
Chili Saltpetre Nitrate of Potash Sulphate of Ammonia
Nitrolim or Calcium Cyanamide - - 154

1 5. PHOSPHATIC MANURES. Bones Superphosphate Basic Slag

Wood Ashes, &c. Limphos - - 156

.6. POTASH MANURES. Kainit Muriate of Potash Sulphate of

Potash - - 158

7. CALCAREOUS MANURES. Chalk Marl Gas Lime Gypsum (Cal-
cium Sulphate) - 159

1 8. MISCELLANEOUS MANURES. Magnesium Salts Iron Salt, or

Chloride of Sodium - - 161

.9. VALUATION OF MANURES - - 162

.10. MIXING MANURES - - 164

SECTION VI INSECT PESTS

Introductory Greenhouse Pests Fumigating Vaporizing Cyaniding
Outdoor Pests Seeking the Cause Life-history and Habits
of Garden Pests Methods of Prevention Chrysalides Table
of Insect Pests - 166

SECTION VII GARDEN FRIENDS

Ladybirds The Devil's Coach Horse The Violet Ground Beetle The
Tiger Beetle Frogs, Toads, and Lizards Hawkflies Ichneu-
mon Flies Lacewing Flies Ear-shelled Slug Spiders The
Weasel Centipedes - 197

SECTION VIIL FUNGOID DISEASES

Introductory Fungoid Diseases of Fruit Trees Fungoid Diseases of

Vegetables '- - - 203

xii Contents

SECTION IX. FUNGICIDES AND INSECTICIDES

Page

Ammoniacal Copper Fungicide or Cupram Arsenate of Lead (Sugar of
Lead) Bordeaux Mixture Carbon Bisulphide Caustic Wash
or Winter Wash Copper Sulphate (Bluestone, Blue Vitriol,
Copperas) Copper Sulphate and Washing Soda (Burgundy
Mixture) Eau Celeste Hellebore Powder Hydrocyanic Acid
Gas Iron Sulphate (Green Vitriol, Ferrous Sulphate) Paraffin
Emulsion (Petroleum, Kerosene, &c.) Paraffin Jelly Paris
Green (Emerald Green, French Green, Mitis Green) Pearl Ash
(Potassium Carbonate) Pyrethrum (Dalmatian Insect Powder,
Persian Insect Powder) Quassia Chips Quicklime Sodium
Cyanide Soft Soap (Whale-oil Soap, Train-oil Soap, Fish-oil
Soap, Potash Soap) Sulphide of Potassium or Liver of Sulphur
Tobacco Winter Washes of Lime and Sulphur Woburn
Wash - - 211

SECTION X. GLASSHOUSE BUILDING
General Greenhouses on Rails - - - 218

SECTION XL HEATING APPARATUS

Boilers Sectional Boilers Setting Boilers Principles of Hot -water

Circulation Quantity of Piping Required Fuel - - 231

LIST OF PLATES

VOLUME I

Page

MARKET CHRYSANTHEMUMS (in colour) - - -Frontispiece

1. Le Peyron. 2. Freda Bedford. 3. Elsie Fulton. 4. Mrs. F. MacNeice.

BULB FARMING AT WISBECH, CAMBRIDGESHIRE ... 4

JAPANESE GARDENING - 16

PERPETUAL CARNATIONS (in colour) - 28

1. Carola. 2. White Perfection. 3. Victory. 4. Enchantress.

DUTCH AND ENGLISH TULIP FARMS - 40

DUTCH AND ENGLISH HYACINTH FARMS - 56

SEED WAREHOUSES - 72

SALPIGLOSSIS (in colour) - - 100

A MIDDLESEX MARKET GARDEN AT DAFFODIL TIME; A CITY OF

GLASSHOUSES AT WALTHAM CROSS, NEAR LONDON - - 130

FLORAL ART - 160

PERENNIAL PHLOXES (in colour) - - 198

1. Crepuscule. 2. Coquelicot. 3. Tapis Blanc.

GENERAL VIEW OF MR. H. 0. LARSEN'S NURSERY, WALTHAM ABBEY;
VIEW OF MODERN GLASSHOUSES AT MESSRS. E. COBLEY & Co.'s
NURSERY, CHESHUNT - - 218

MODERN GLASSHOUSES - - 222

INTERIOR VIEW OF MODERN GREENHOUSE - 226

GREENHOUSES ON KAILS, SHOWING MOVABLE ENDS AND KAIL BETWEEN;

INTERIOR OF GREENHOUSE ON RAILS, SHOWING CROP OF NARCISSUS 230

TREES AND SHRUBS PACKED FOR EXPORT TO AMERICA AT MR. J.
SMITH'S NURSERY, DARLEY DALE, DERBYSHIRE; FORCED LILAC
PLANTS GROWN IN POTS FOR EXHIBITION - 236

xiii

SECTION I

General Aspects of Commercial
Gardening

During the past fifty or sixty years horticulture has sprung into a
prominent position as one of the leading industries of the United King-
dom. Horticulture, unlike its twin sister agriculture, is not represented
in Parliament, and the only legislative notice taken of it has been to
make its disciples pay rates and taxes on their skill and industry. When
we have a Minister of Horticulture, as the French and Belgians have,
then perhaps the horticultural trade will receive as much consideration
as agriculture does in connection with the rating of the land, and more
importance will be attached to it as a national industry.

Horticulture, as distinct from agriculture, has to deal with the cultiva-
tion of all kinds of plants and flowers, fruits and vegetables, both in
the open air and under glass. Besides our native hardy fruits, flowers,
and vegetables, the horticulturist also has to grow exotics from all parts
of the world from the tropics, subtropics, and temperate regions, from
the mountains and valleys, and from all kinds of soils and situations.
To bring these to perfection necessitates considerable skill, besides great
expense. The horticulturist has found out that the rather antediluvian
methods of the agriculturist would be of little use to him. He must
mix his soils and composts in various ways to suit particular crops, and
he must regulate the temperature by means of glasshouses and frames
and hot-water apparatus if he is to succeed. This necessitates outlay in
other directions, and the timber, glass, and iron trades benefit by his
enterprise, as well as many others that supply horticultural sundries.
Indeed it is almost impossible to describe the intricate details of horti-
cultural practice, and it must suffice to say that they are such as would
astonish the average agriculturist. Although both farmer and gardener
have to practise the same principles of cultivation for outdoor crops,
the gardener, even with these, will devote far more attention to detail,
and will spend an amount of money every year in cultivation that the

farmer would consider exorbitant or extravagant. The farmer leaves
VOL. I. 1 J

Commercial Gardening

a good deal to nature; but the gardener, and especially the commercial
gardener, cannot afford to leave his various crops altogether exposed to
the mercies of a somewhat fickle climate. He prepares his soil to a greater
depth, and feeds it more richly with manure than does the farmer; and
he also pays greater attention to cultural details. In addition, he must
gather his crops, not for cattle, but for human consumption, just when
they are ready, and he must pack them in such a way that they will
readily attract buyers in the markets. At one time, indeed, the market
gardener was little better than a farmer in his cultural and business
methods, and he sent produce to market in a very slipshod manner. The
stress of competition at home and the importations from abroad, however,
have completely changed the methods of the modern market grower. He
has found out by experience that the finer, better, and cleaner his produce,
and the better it is packed or displayed, the higher the prices and the
quicker the sales. He has learnt much in these respects from the way
produce from the Colonies and from the Continent is placed on the
markets, and he realizes that good stuff badly displayed will often fetch
miserably low prices.

This work on commercial gardening deals principally with those
classes of plants that are grown in large quantities either in the open
air or under glass for sale in the London and provincial markets, and
also those that are grown by nurserymen and hardy-plantsmen in fairly
large numbers to meet the demands of their customers who do not
patronize the markets. There are, indeed, so many ramifications of the
horticultural trade, each intimately associated with the other, and depen-
dent on each other, that it may be well to say a few words about each
to show how one is linked up with the other.

The Seed Trade. This branch of commercial gardening has assumed
immense proportions of late years. In various parts of the kingdom firms
have established trial grounds where their seeds are not only saved, but
where new varieties likely to have a ready sale are also tested and proved
before being placed upon the market. This work necessitates great care
and cultural skill; and expensive machinery, driven by steam or the more
modern electricity, is used to cleanse the seeds from impurities of every
sort. Large warehouses have to be built to accommodate the stocks, not
only of home-saved seed, but also of that imported from sunnier climes
than our own. To give some idea as to the trade done in seeds it is only
necessary to state that one firm alone sells each year about 50,000 bus. of
culinary Peas: 51,000 bus. of root-crop seeds; 6500 bus. of Beans; 41 tons
of seeds of the various Cabbage crops; 1300 bus. of Radish seeds; 25 tons
of Beet seed: 1400 bus. of Spinach seed; 10 tons of Onion seed; 17 tons of
Carrot seed; 220 bus. of Parsley seed; 10 tons of Parsnip seed; 15 tons
of Sweet Pea seed; 14 tons of Nasturtium (Tropaeolum) seed; and 3 tons of
Mignonette seed. Seeds of annuals, biennials, and perennials of all kinds
are sold in large quantities year after year, and are retailed in packets
costing from Id. upwards.

General Aspects of Commercial Gardening 3

The Bulb Trade. Although a large proportion of the bulb trade is
undoubtedly Continental, there has been a magnificent effort on the part
of British and Irish growers to produce large quantities at home. While
such bulbs as Hyacinths and Tulips and Daffodils have been for genera-
tions a staple industry of the Dutch growers, signs are not wanting that
equally good bulbs can be grown in several places in the United Kingdom.
With the exception perhaps of Hyacinths, other bulbs of a hardy nature
might be grown more extensively. In the Channel Islands and the Scilly
Islands, in parts of Ireland and England, Tulip and Daffodil bulbs are
now grown on a large scale and of the finest quality, but the methods
of British growers in calling attention to their stocks are far inferior to
those adopted by the Dutch. The latter band themselves together for
mutual trade benefit, and make a point of encouraging visits to their
bulb farms every season. The trade practically commences in the spring,
when Dutch growers book orders from the visiting growers, and deliver
the goods as early in autumn as possible. During the summer months
from May to August their travellers invade the British Islands and
America, and push the bulb trade so well that they take home fine fat
orders for early autumn delivery. From September to December the
trade is brisk amongst retailers, while the market grower has already
boxed his bulbs of Tulips, Daffodils, Hyacinths, Crocuses, Snowdrops, &c.,
to secure an early Christmas and Easter trade.

Tulips, Daffodils, Hyacinths, and Crocuses are abundant from Christmas
to Easter; while Lilium longiflorum is now practically in season through-
out the year. Gladioli of the Colvillei and nanus sections are also useful
for spring work, while the Brenchleyensis, Childsi, and Nanceianus sections
come in for late summer or early autumn work.

Apart from bulbs proper, such tuberous-rooted plants as Arum Lilies
are in great request from Christmas to Easter and Whitsuntide, the chief
trade being done in the blooms or spathes.

Ixias, Freesias, Snowdrops, German, Spanish, and English Irises,
Tuberoses, Montbretias, Solomon's Seal, Crown Imperials, Herbaceous
Paeonies, Eucharis, Dahlias, &c., are amongst other bulbous and tuberous
plants that find a ready sale throughout the year at their own particular
season, for the cut-flower trade. Each group is dealt with in its proper
place in Vol. II of this work.

Amongst retail nurserymen and bulb merchants other bulbous and
tuberous plants dealt in, as well as those mentioned, are Begonias,
Dicentras, Gloxinias, Hippeastrum, Leucojum, Chionodoxa, Scilla, Alstroe-
meria, Brodiaea, Brevoortia, Galtonia, Hsemanthus, Ranunculus, Winter
Aconite (Eranthis), Calochortus, Camassia, Colchicum, Erythronium or
Dog's Tooth Violet, Eremurus, Incarvillea, Ixiolirion, Lycoris, Milla or
Triieleia, Muscari or Grape Hyacinth, Ornithogalum or Star of Bethlehem,
and many others, including the Water Lilies or Nymphaeas which have
become popular of late years. Most of these are practically hardy, and
the trade in them is confined to nurserymen and hardy-plantsmen who

Commercial Gardening

deal with the owners of private establishments. Each genus is dealt
with amongst the "Plants and Flowers" in Vol. II.

The Hardy -plant Trade. Of late years the trade in hardy plants
has assumed almost gigantic proportions. Not only are large quantities
of hardy herbaceous perennials actually sent to the various markets for
sale packed in various ways and sold as "roots", but a still larger trade
is done through the post, by means of exhibitions, and by advertising
in the papers. Owing to the cost of erecting glasshouses, the cost of
fuel, and other items of expense many private people have discarded glass
altogether, or the newer generation has not taken a fancy to it owing
to the trouble and expense. To such, the hardy herbaceous perennials,
and hardy annuals and biennials, naturally appeal with great force.
There is no need to have glasshouses of any description to grow these
plants, and even a cold frame can be dispensed with; and yet a mag-
nificent display may be secured by a judicious selection of plants that will
flourish in the open air in most parts of the kingdom without any artificial
protection. This being the case, it is not to be wondered at that a large
trade has sprung up in these plants, and something like three or four
thousand different species are now dealt in by various growers, some of
whom hold valuable stocks of the best-selling kinds, while others cater for
a select group of plant connoisseurs and botanical establishments.

The grower of hardy plants, as a rule, does not go to market, and
his methods of business .are quite different from those of the market
grower. He relies very largely for his sales upon his catalogues (which
are often works of art), upon exhibitions in all parts of the kingdom,
and upon judicious advertising, very much in the same way as the
seedsman and bulb merchant do. Thousands of people now interested
in gardening will gladly pay a reasonable price for a plant in which
they are interested, and they will visit flower shows and exhibitions in
the hope of seeing something new, or something they would like to have
in their collection. The hardy-plantsmen, therefore, who make a practice
of displaying their specialities at the various exhibitions up and down
the country stand an excellent chance of making new customers if they
exhibit really choice and well-grown stuff', and set it up with all the
art of window dressing. The old style of jumbling plants up "anyhow"
at an exhibition is no longer sufficient. The exhibitor adopts various
devices, and when space permits he makes miniature herbaceous borders,
rock gardens, water gardens, and he arranges his goods in such an
artistic way that the would-be purchaser is at once captivated, and longs
to produce a similar floral picture in his own garden. This naturally leads
not only to the sale of plants, but also to the engagement of landscapemen,
who know how to turn a piece of waste land into a smiling flower garden.
Many firms now make a speciality of laying out gardens artistically and
naturally, and although some amateurs try their untrained hands at the
business, they generally have to call in the aid of the man who knows his
plants and their nature and uses by everyday intercourse and experience.

A FIELD OF NARCISSUS

A FIELD OF SPANISH IRISES

BULB FARMING AT WISBECH, CAMBRIDGESHIRE

(Mr. J. W. Cross)

General Aspects of Commercial Gardening 5

While exhibiting is one of the best means of doing business for the
grower of hardy plants, it must be remembered that it entails a large
expense. The mere carriage of the plants by rail or road, apart from
hotel and other expenses, often means a substantial sum, the recovery
of which will depend largely upon the weather and upon the class of
visitors to the exhibition.

Some growers of hardy plants rarely exhibit, but rely upon the post
and advertisements to dispose of their goods. Hundreds of thousands
of young plants and cuttings are sent through the post to the most
remote parts of the kingdom, to fill orders that have come to hand as
the result of reading an advertisement. Some, indeed, spend from 50
to 100 a week during the season in advertising alone, and this will
give some idea as to the volume of the trade. Not only are hardy
plants disposed of rapidly in this way, but also half-hardy and tender
plants during the season, as may be seen by referring to the advertise-
ment columns of the trade and amateur papers.

From what has been said it will be gathered that the great trade in
hardy plants of all kinds, and in seeds and cuttings, as well as in bulbous
and tuberous plants, is largely done by means of judicious advertising.
The plant grower not only supports the newspapers, but he also places
large orders with the printers for thousands of catalogues that are issued
broadcast, but not without considerable expense. Some of the larger
firms issue as many as eighty thousand beautifully prepared catalogues
every year, weighing in the aggregate from 90 to 100 tons; while smaller
men print and distribute catalogues according to their means. In all
cases, however, the General Post Office, the printers, and newspaper pro-
prietors have had the first pick at the seedsman's or hardy-plantsman's
purse, and he is left to settle his account with a more or less fickle public.

The Nursery Trade. This branch of commercial gardening has
extensive ramifications all over the kingdom. All kinds of plants, fruits,
flowers, and vegetables are grown for sale in the open or under glass,
and thousands of gardeners are employed to propagate and grow them.
There are many special branches in the nursery trade. Thus some make
a speciality of Roses, some of fruit trees, some of ornamental trees and
shrubs, some of stove and greenhouse plants, some of Ferns, some of
Orchids, some chiefly of forest trees, some of hardy herbaceous perennials
and alpines, and rock and water plants and perhaps not one of these
nurserymen ever sends a plant to a market. The nurseryman is quite
distinct in his methods of trading from the market grower and the market
gardener. He makes a speciality of various classes of plants, and has every
nook and corner of the globe ransacked by horticultural travellers, who are
on the lookout for any new plant likely to attract attention.

Besides pushing his trade by means of travellers, advertisements, and
catalogues, the nurseryman proper also relies largely upon exhibitions.
These are held regularly not only in London, where the finest class of
trade is done, but in almost every town of any importance in the kingdom,

6 Commercial Gardening

at different periods of the year. In some cases exhibitions on the Conti-
nent are also visited, and in this way some firms have worked up a large
international or cosmopolitan trade. These exhibitions naturally cost
much money, not only for transport, but for the maintenance and lodging
of the necessary staff; and it is essential to reap a good harvest in the
way of orders to enable one to pay the expenses and leave a balance on
the right side.

Market Gardening- and Market Growing-. The business of the
market gardener and the market grower is different in a technical sense.
The market gardener proper, as a rule, grows fruits and vegetables on
a large scale in the same way that the farmer grows corn and root crops.
If he indulges in glass at all it is a few frames at the most to raise early
supplies of seedlings to put out at the first favourable opportunity in
spring; or he may use bell glasses or cloches to protect his early cauli-
flowers and marrows, much in the same way as the French cultivators do.

Market gardening has been a great industry in the Thames valley for
generations, and notwithstanding the operations of the builder, and the
enormous growth of the London suburbs, there is still a large area around
the metropolis devoted to market gardening. Of course the market
gardener is being pushed farther and farther out, but with improved
methods of transit, and better roads, the man twenty or thirty miles from
London is probably in as good a position as his predecessor was fifty or
sixty years ago, when only a dozen miles from Covent Garden. Old
market-garden districts like Deptford, Fulham, and Chelsea have been
wiped out by the builder, and buildings and roads now take the place
of cabbages, rhubarb, fruit trees and bushes that not so many years
ago made those neighbourhoods truly rural. This pressure from the
centre has naturally driven the market gardener farthei out, and such
places as Feltham, Ashford, Sipson, Staines, West Drayton, Harmonds-
worth, Bedfont, Shepperton, Stanwell, and Cranford, in Middlesex, are
becoming covered with fruit and vegetable gardens. Kent, Surrey, and
Essex are being invaded in much the same way, and there seems to be
a tendency to increase the acreage under these crops. From Mortlake
to Richmond and Petersham, on the south side of the Thames, market
gardens still exist, but it will probably not be for very long. Chiswick,
on the north bank, still contains some of its ancient market gardens, and
these extend to Brentford, Isle worth, Heston, and Hounslow; but in these
famous market-garden areas the builder is rapidly covering the ground
with bricks and mortar. The vale of Evesham in Worcestershire has
become famous as a centre, not only for the market culture of fruits and
vegetables, but also as the first place in the British Islands where " inten-
sive cultivation " as practised around Paris was established. For particulars
of this system the reader is referred to Vol. IV.

While the market gardener is seeking fresh fields for his labours,
the market grower who brings his crops to maturity under glass has
come very much to the front during the past thirty or forty years.

General Aspects of Commercial Gardening 7

There are now enormous areas of glasshouses erected all round the
metropolis, but more especially to the north in such places as Edmonton,
Ponder's End, Enfield, Waltham Cross; in the north-west round Finchley,
Whetstone, and Potter's Bar; and to the west at Isle worth, Feltham,
Hillingdon, Uxbridge, Sipson, and West Drayton. In other parts of the
kingdom, notably Worthing and the Channel Islands (principally Guern-
sey), large areas of ground have also been covered with glass. This has
naturally led to the development of other businesses, such as the timber
trade and the iron trade. Glasshouses are now built on quite different
principles from what they were twenty or thirty years ago, and growers
are at last beginning to realize the great value of light to their crops, and
to appreciate structures that will allow the maximum amount of sunshine
through the glass. Less wood and more glass is now the rule. In the
iron trade, enormous quantities of material are used for the manufacture
of boilers and pipes; while the manufacturers of paint, putty, and other
materials also do a brisk trade with market growers. To these must
be added the various gas companies and colliery merchants, who provide
thousands of tons of coke or anthracite coal to feed the furnaces attached
to the glasshouses.

The crops grown under glass are naturally of a quite different nature
from those grown in the open air. They require greater care and skill
in cultivation, and frequent changes are made in accordance with the
alterations in fashion or the fluctuations of the market. Cucumbers,
Tomatoes, Grapes, Ferns, Palms, Aspidistras, Chrysanthemums, bedding
plants, Melons, Peaches, constitute some of the chief crops grown exten-
sively under glass, and they are all dealt with in their proper places in
Vols. II, III, and IV of this work. Such outdoor crops, however, as Cab-
bages, Lettuces, Radishes, Mint, Rhubarb, Sea Kale, Dwarf and Runner

o ' * '

Beans, Marrows, &c., are also now grown extensively under glass by many
to supply the early markets and thus pander to the fashion of having
everything in as early as possible before its natural period.

Notwithstanding the numbers of market growers who now send pro-
duce to the London and provincial markets, it is astonishing to see the
enormous quantities of fruits, flowers, and vegetables that are imported
from the Continent and the Colonies. The increased speed of trains and
steamboats now renders it possible to bring supplies to market that a few
years ago would have been considered impossible. The introduction of
the refrigerating system on trains and steamboats has still further aided
the introduction of colonial and foreign produce to British markets one
of the surest signs that they are the most lucrative in the world. If they
were not, supplies would soon cease, and trade would flow to the markets
where the " biggest penny " was to be secured.

The Florist Trade. There is scarcely a town of any pretensions in
the British Islands that does not boast of at least one florist's shop. In
large provincial towns there are many, and in the metropolis itself and
its suburbs there are many hundreds. The floral trade has developed

8 Commercial Gardening

enormously during the past twenty or thirty years, and the florists' shops
are the main outlets for most of the decorative plants and flowers grown
by market nurserymen. It would indeed be a poor prospect for the latter
if the business of the florist was interfered with or hampered by increased
burdens of taxation. The more florists there are in the country the better
for the growers of plants and flowers. Incidentally, the florists' shops are
a sign of the general prosperity of the people, because their trade may
be regarded more in the light of a luxury of art and taste than as an
actual necessity.

The business carried on by the florist is of a varied character. He is
an adept at the making of bouquets of all kinds for weddings or Court
functions. Wreaths, crosses, anchors, pillars, cushions, and numerous other
floral emblems for the departed also come within his sphere of influence,
in addition to which he sells masses of cut flowers in a natural state, as
well as decorative pot plants, little shrubs, &c. And where the florist
happens to be also a nurseryman, he undertakes landscape work and
jobbing. In all these operations his raw material consists of plants and
flowers of all descriptions, hardy and tender, and he is ever on the watch
to invent new designs, or to arrange his flowers, &c., in such a way that
they will attract attention and excite admiration. Some of the leading-
London florists have made their names famous by the taste and original
ideas they display not only in the making of wreaths, bouquets, &c., but
in the artistic way they decorate or furnish banquet halls, theatres,
reception rooms, &c. All important public functions in any town or
city lead to business being done by the florist; and he who displays the
greatest taste, originality, and industry is the one most likely to be
patronized.

The florist and furnishing trade indeed cannot be learned in a day.
Many an excellent grower of plants and flowers used in floral decorations
would make but a sorry job of it if he had to arrange his own procce
for a public function. It takes years to become an expert florist, and in
some branches of the trade, such as the making of wreaths, bouquets, &c.,
women stand as good a chance as men, if not a better. The operator
must be not only skilful and quick in " mounting " the flowers on various
kinds of wires and "foundations", but must display considerable taste in
the arrangement of the individual flowers, and of their effects upon one
another. It is quite possible for the choicest flowers to be as easily
spoiled in effect in the hands of an incompetent florist as it is for good
viands to be spoiled in the hands of an incompetent cook. A skilled
florist will produce a finer effect with a few inexpensive blossoms than
an unskilled one will with a cartload of choice material, just as some
women can dress charmingly at little expense while others will look
dowdy in the finest materials and jewellery.

There is no end to learning in the florist's business, and the fashion
of to-day may be out of date to-morrow. Great and wonderful changes
have taken place within the past thirty years in the way flowers are

General Aspects of Commercial Gardening 9

arranged. Formerly bouquets were made in a round, flat, and dumpy
style, having row after row of flowers arranged in circles round the
centrepiece. The whole arrangement was flat and formal, and was
finished up with a collar of fancy paper. This heavy style of bouquet
has long since disappeared, and a lighter and more graceful arrange-
ment has taken its place. This has been brought about by the introduc-
tion of different kinds of flowers and trailing plants, and the different
methods of sending them to market. Twenty and thirty years ago
nearly all flowers were cut with very short stalks, so that the florist,
to produce any effect at all, was obliged to mount many of them on
wires to raise them above their neighbours. In these days, however,
florists insist on having flowers with the natural stems as long as possible,
so that a variety of designs is more easily obtained. The grower who
would now send short-stemmed Roses or Carnations to market would find
his wares on his hands when the market closed. With some classes of
flowers, such as Camellias, Tuberoses, and Eucharis, it is impossible to
supply long stems to the individual flowers, and what they lack in this
respect must be made up by the florist in other ways.

Amongst the most important of the florist's accessories are wires of
various kinds, and moss for the foundations of wreaths, crosses, anchors,
and other emblems. The stiffish wires used for mounting flowers are
known as stubs, and are of varying length and thickness, according to the
purposes for which they are required. Special wires are also used for the
mounting of Roses, Camellias, Tuberoses, &c., and it takes some considerable
time for the beginner to find out, not only the proper stubs and wires to
be used for certain purposes, but to acquire that manual dexterity which
distinguishes the expert from the tyro.

The foundations of various sizes and shapes are made of strong galvan-
ized wire by the horticultural sundriesman, so that they will not bend or
twist when in use. These foundations are covered with soft moss tied on
with string or wire, and into the moss the flowers, mounted on wires or
stubs, are stuck. Years ago, before the use of stubs became common,
flowers were tied down to the moss foundations, and the general effect
was flat and unrelieved. Nowadays, however, flowers can be arranged
in various styles some flat, some slightly raised, some bunched boldly in
certain places and forming the piece de resistance of the whole work all
of which variations depend upon the artistic perceptions of the operator.
Owing to the more frequent interchange between British and Continental
florists now than formerly, constant changes are taking place, and one
notices how largely the ideas of the Continental florists are being assimi-
lated by their British brethren, and vice versa.

Popular Florists Flowers. Perhaps the florist attaches more impor-
tance to the colour than to the form of the flowers he uses in his business.
As a rule, flowers with clear and distinct shades of colour are most appre-
ciated; while those with confused tones or lacking in brilliancy are prac-
tically useless. A colour that will not show up well at nighttime under

io Commercial Gardening

gas-light or electric light is of little use, because a good deal of the
florist's art is seen under these conditions.

White Flowers. Taking the colours all in all, white is undoubtedly the
most popular, and enormous quantities of white-flowered plants must be
grown to meet the ever-increasing demand. Amongst the most important
plants used for a supply of white flowers to the florists the following may
be mentioned: Lily of the Valley; Lilium longiflorum (Harrisi); Lilium
speciosum or lancifolium album,; JSucharis grandiflora ; Camellias;
Tuberoses (Polianthes); Freesia refracta alba; Tulip, La Reine; Roman
Hyacinths; Florists' Hyacinth, La Grandesse; Gladiolus Colvillei, The
Bride; Stephanotis; Lapageria alba; Bouvardia; Rose, Niphetos; Gar-
denias; Carnations; Phlox; Chrysanthemums; Dahlias; China Asters;
Stocks; Azaleas; Pink, Mrs. Simkins and Her Majesty; Zonal Pelargonium
Hermione (double); Gloxinias; Snowdrops; Paper-white Narcissus; Star
of Bethlehem (Ornithogalum); Odontoglossum crispum; Christmas Roses
(Helleborus niger); Arum Lilies (Richardia); Hoteia (Spircea) japonica;
Gypsophila paniculata and G. elegans; Achillea, The Pearl; Sweet Peas;
Spanish Iris; Florentine Iris; Paeonies; Plialcenopsis grandiflora, amabilis,
RieTnstedtiana, &c.

Apart from white, flowers of all other colours are utilized in great
abundance, and the principal kinds used may be noted as follows: Roses
of all kinds; Violets, double and single; Carnations Perpetual and Border
varieties; Daffodils and Narcissi; Tulips; Hyacinths; Gladiolus; Dahlias;
Chrysanthemums ; Phlox ; Forget-me-nots ; Zonal Pelargonium Raspail,
double scarlet; Orchids such as Cattleyas, Dendrobiums, Oncidiurns, Odonto-
glossums, Laelias, and Phalsenopsis.

Trailers. For " shower " bouquets, festoons, and table decorations it is
useful to have certain plants with slender trailing stems and foliage that
will not soon wither. Amongst the best plants for this purpose are
Asparagus Sprengeri, A. plumosus, and A. plumosus nanus (all known
as Asparagus "Ferns"), A. medeoloides (or Myrsiphyllum asparagoides)
far better known to florists as " Smilax ". A great trade is done in the
trails of these plants, and some growers make a speciality of their culture.

Foliage. For backing up many flowers used in wreaths, crosses, bou-
quets, &c., it is sometimes essential to have foliage that will throw the
blossoms into greater relief, and a large number of plants are grown for
this purpose. Until the various kinds of Asparagus were introduced, the
fronds of the Maidenhair Fern were used in enormous quantities for almost
everything. Of late years, however, the foliage of other plants has been
utilized, and florists now stock in the proper season the leaves of such
plants as: Crotons, Maples, Holly-leaved Barberry (Berberis Aquifolium),
Copper Beech, Ivy, Copper Hazel, Purple Plum, Scarlet Oak, Galax
aphylla, large-leaved Myrtle, &c., to which must be added for winter work
sprays of Mistletoe and of Holly in leaf and berry. There is still a great
trade done in what is known as "French Fern" (Asplenium adiantum-
niqrum\ the fronds of which are sold in bunches. The old conventional

General Aspects of Commercial Gardening u

ideas, however, are gradually vanishing, and it is now customary to use
the natural foliage of any flower that may be used in floral work. Thus
violet leaves are most appropriately used with violet blossoms, as holly
leaves are the most suitable adjuncts to the scarlet berries. Indeed there
is no end to the methods employed by the modern florist to produce
a charming effect; and the plant and flower grower who will introduce
a new plant, or suggest a novel idea, is looked upon as a floral friend.

Tree and Shrub Trade. This is a very important branch of com-
mercial horticulture, and one about which the general public knows but
little. It may be divided into two principal groups, viz.: (1) that dealing
with forest trees, and (2) ornamental flowering trees and shrubs.

In regard to forest trees it is astonishing what an enormous number
of young plants are raised every year in different parts of England,
Ireland, and Scotland. Those who are under the impression that British
forestry is a dead or dying industry have no idea as to the amount of
business done in forest trees, and it is a pity that the Chancellor of the
Exchequer and the officials of the Board of Agriculture are not better
informed as to what is being done in this respect. There are hundreds
of capable men, who could not only plant all the waste land in the United
Kingdom in a comparatively short time, but who could produce millions
of young forest trees annually to fill the gaps that might occur. And yet
Mr. Lloyd George, when introducing his famous 1909 Budget, said in
reference to the scheme of afforestation : " I am also told that we cannot
command the services in this country of a sufficient number of skilled
foresters to direct planting. I am advised, and, personally, I am disposed
to accept that counsel as the advice of prudence, that the greater haste in
this matter will mean the less speed, and that to rush into planting on a
huge scale without first of all making the necessary experiments, organizing
a trained body of foresters, and taking all other essential steps to ensure
success when you advance, would be to court disaster which might dis-
courage all future attempts."

It would be interesting to know whose advice the Chancellor of the
Exchequer relied upon when he stated that " we cannot command the
services in this country of a sufficient number of skilled foresters to direct
planting", but there was no doubt about its misleading character. We
wonder what kind of men they are who raise and plant thousands of forest
trees annually? Have they no knowledge of the trees they raise, and are
they not skilled in planting and growing them? The Chancellor's some-
what misleading statement is calculated to injure the reputation of a large
number of skilful and hard-working men who earn a living by carry-
ing out the very duties which the Chancellor was advised were not and
could not at present be performed. These men, skilled in the raising,
planting, and cultivation of forest trees, may not, of course, be able to pass
an examination in Greek and Latin, or in Conic Sections and Trigonometry,
nor have they had the disadvantage of a "public-school training"; but
they know their business, and if the Chancellor of the Exchequer will only

12 Commercial Gardening

start the Government Afforestation Scheme at once, he will find plenty
of skilful foresters who will see that the preparation and planting of the
17,000,000 acres of waste ground in the United Kingdom are carried out
properly.

Raising Forest Trees. The simplest method of raising these is from
seeds. These are collected when ripe in autumn and carefully stored until
the spring. In some cases, however, like the Willow, Poplar, Elm, in
which the seed ripens early, sowing may take place during the summer
months. The seed land is prepared by ploughing or digging, and harrow-
ing and raking, until it is brought to a fine tilth. Drills are then drawn
at regular distances apart, varying from 3 in. to 12 in. according to the
kind of seed that is sown, each kind being covered with three or four times
its own depth of soil, and afterwards lightly rolled. In some cases seeds
are sown broadcast over beds about 5 ft. wide, but generally speaking it is
more economical, and better for the seedlings, to sow thinly in drills. To
allow for cultural attention like weeding, hoeing, watering, &c., the seed-
beds should not be more than 4 to 5 ft. wide, with an alley between, so that
half the seed-bed may be attended to from one side and half from the
other without having to tread upon the soil between the plants.

The forest and other trees raised in large quantities from seed are Oaks,
Beeches, Birches, Ashes, Poplars, Sweet Chestnuts, Horse Chestnuts, Elms,
Hollies, Hawthorns, Hornbeams, Limes, Mountain Ashes, Planes, Syca-
mores, False Acacias (Robinia), Maidenhair Trees (Gingko), Willows, Tulip
Trees (Liriodendron), and such conifers as the Firs, Spruces, Pines, the
Arbor Vitse, Cedars, Thuyas, Larches, Cypresses, &c.

Apart from the forest trees, there are hundreds of others of a more
ornamental character, chiefly used for the decoration of large parks and
gardens, public places and squares, streets, &c. These are raised not only
from seeds in the same way as forest trees, but in the case of special
varieties, or when seeds are not ripened in abundance, they are also raised
by means of cuttings, layers, buds, grafts, and suckers. The most impor-
tant plants in this group and in the forest section are dealt with in Vol. II
in the article on " Trees and Shrubs ", to which the reader is referred.

Of late years a great trade has sprung up, chiefly amongst nurserymen,
in ornamental flowering shrubs, which are grown in pots and gently forced
into early bloom in Spring (January to March and April). The principal
plants thus grown are Lilacs, Double Cherries, Azaleas, Almonds, Japanese
Quinces, Wistaria, Double Plums, Cydonia Maulei, Pyrus spectabilis,
Deutzia gracilis, Staphyllea colchica, Prunus triloba, Magnolia Soulan-
geana, Forsythia suspensa, Ribes sanguineum, &c. &c.

A trade also has sprung up again in clipped trees and shrubs of an ever-
green character. Such trees as the Box and the Yew, the Poet's Laurel,
and others are cut into various shapes, some more or less fantastic as
shown in the photograph (fig. 1). They are usually grown in tubs, and
are utilized for what some people call decoration, but others desecration,
of large gardens. [j. w.]

General Aspects of Commercial Gardening 13

Photo. Clias. L. Clarke

Fig. 1. Clipped Trees and Shrubs

Japanese Gardening 1 . Although the introduction of the beautiful
Japanese plants that now contribute to the charm of British gardens
belongs to the distant past, it was not until some fifty years ago that
commercial cultivators gave serious attention to the Japanese flora with
a view to obtain some other of its members for the further enrichment
of our gardens. If until the middle of the last century Japan was not
exactly a sealed book to the seeker after new forms of tree and plant
life, the restrictions imposed upon the members of other nationalities
were such as to render it extremely difficult for them to obtain access
to the country, much less to explore meadow or woodland, or plain or
mountain, and bring away on their return home the spoils of the ex-
ploration. The removal of these restrictions by the opening of the
Japanese ports to foreigners rather more than half a century ago gave

14 Commercial Gardening

the desired opportunity for collecting some of the many beautiful trees,
shrubs, and other plants that were likely to succeed under the climatic
conditions that obtain in the United Kingdom, and placing them at the
disposal of the general body of plant lovers. Then as now the nursery
firms of this country were remarkable for their enterprise, and there-
fore not slow to take advantage of the opportunity thus given them
for enriching gardens with new and beautiful forms of plant life.

As a proof of this one example will be sufficient. In April, 1860, the
late John Gould Veitch, a member of the well-known Chelsea firm, left
England on a voyage to the Far East, and arrived at Nagasaki in the
July following. He remained in Japan about twelve months, and during
that period he sent home a large number of trees, shrubs, and bulbous
and other plants, and of these the greater proportion have proved of so
high a degree of value as to obtain a place in gardens generally. Coni-
ferous trees included Abies firma, A. microsperma, Cryptomeria japonica
elegans, Juniperus chinensis aurea, Larix leptolepis, Picea Alcockiana,
P ajanensis, P. polita, Pinus densiflora, P. parviflora, P. Thunbergi,
and the varieties of Retinospora obtusa. The deciduous trees included
the varieties of Acer palmatum, the climber Ampelopsis tricuspidata
(or Vitis inconstans), and the plants Lilium auratum, Primula japonica
and P. cortusioides. The introduction of so many kinds of first-rate im-
portance within so short a period evinces much enterprise, for travel-
ling in Japan was very different in those days from what it is at the
present time. The Abies, Cryptomeria, Piceas, and Pinus represent species
that rank high in their respective genera, and the varieties of Retinospora
obtusa are so diversified in form and colour, and withal so attractive,
that they have throughout the period that has elapsed since their intro-
duction enjoyed a high degree of popularity and have been freely used
in the creation of garden scenery.

The varieties of Acer palmatum, in the varied form and colour of
their elegant foliage, are recognized as forming a group of small-grow-
ing trees of immense value for garden decoration; and Ampelopsis tri-
cuspidata is used more largely in clothing wall surfaces than all the
other climbers combined, and it contributes in no small degree to the
amenities of town life. The richly coloured Primula japonica continues
to be highly appreciated as one of the best of the moisture-loving plants
for fringing streamlet and pool in shady positions, and as the result of
the activities of various commercial horticulturists the varieties of
Primula cortusioides have been so multiplied as to form a large group
in which there is so great a range of colour as to greatly enhance their
value for various decorative purposes both under glass and in the open.

The plants thus briefly enumerated rapidly came into favour. They
were largely used, and soon made an impression on the scenery of gardens
where novelties of merit received a welcome. They greatly enhanced the
interest and attractions of gardens in which they were given a place, and
as a result they greatly stimulated an interest in Japanese plants, and

General Aspects of Commercial Gardening 15

gave rise to so strong a demand as to tax severely the resources of
nurseries for a long series of years, and have an immense influence for
good upon a great industry. They had another effect in their relation
to the garden, and that was to quicken an interest in rare and beautiful
plants from other parts of the world, by showing that there were subjects
other than timber trees and the common laurel suitable for furnishing the

garden.

In the case of Lilium auratum there was a brisk demand for bulbs
at a comparatively high rate, and when it became possible to supply
them at a price which placed them within the reach of practically all
owners of gardens, the demand increased to an enormous extent. For
forty years or more the importations of the bulbs of this Lily have
annually been on such a large scale as to represent a trade of consider-
able importance and to occupy a prominent position in the business of
those who are concerned with the distribution of bulbs. Lilium longi-
florum, which was introduced to this country in the year previous to
John Gould Veitch's voyage to Japan, has enjoyed a higher degree of
popularity than even that of L. auratum, not because of its flowers
being superior in beauty, but because of their adaptability for decora-
tive purposes. To the florists they are of immense value, for they can
be used more or less successfully in wellnigh all forms of the decorative
art, and with the aid of the refrigerator in retarding the bulbs they
can be had in abundance at all seasons of the year.

British cultivators are no longer wholly dependent upon Japanese
growers for their supplies of bulbs, but they annually obtain large im-
portations from them. The demand for this beautiful and useful Lily
is very great, and the importation and distribution of the immense
numbers of bulbs that are annually required in market-growing establish-
ments and private gardens has become so important a detail of com-
mercial horticulture that one could wish statistics showing the exact
quantities that annually reach this country from Japan were available.
Lilium speciosum, which also forms an important part of the trade in
Lily bulbs with Japan, was introduced from that country in 1833; but
since that year the Japanese growers of Lilies have sent us varieties of
this species which are so superior in the size, form, and colouring of
their flowers as to surpass those of the typical white and coloured forms
and to render them of quite secondary importance.

Of much interest is Iris Kcempferi, which was introduced to this
country from Japan in 1857, and attracted much attention when the
large handsome and richly coloured flow T ers were first presented to public
notice at the exhibitions, and began to make their appearance here and
there in private gardens. For a time they failed to make the headway
that was anticipated, and this was in a large measure due to the cultural
details being then imperfectly understood. Many of those who planted
this Iris in its varied forms failed to recognize the fact that to achieve
success the roots must have the run of a rich and moist soil, an abun-

16 Commercial Gardening

dance of moisture being especially necessary during the season of growth.
Hence large numbers were planted in beds or the mixed border, without
reference to their special requirements in the matter of food or moisture.
The growth was consequently unsatisfactory, and in course of time their
cultivation was greatly reduced. Within the past few years there has
been a great revival in the interest evinced in this and other of the
Japanese Irises.

The lessons that the Japanese growers have been able to teach us
have been taken to heart, and moist positions are selected for the moisture-
loving Irises, and, if these cannot be provided, care is taken to main-
tain the soil in a thoroughly moist state throughout the whole period
when the plants are in an actively growing state. The influence of the
Iris gardens of Japan has been felt in many gardens of this country, and
in not a few, large plantings have been made on the lake side and along
the margin of pools, and constitute delightful features. These examples
are of interest as showing that if we cannot have displays of Irises equal
to those which have made the gardens of Hori-kiri famous, we can with
their aid have in this country floral pictures of wondrous beauty.

Among the Japanese trees and shrubs that have been introduced but
have not as yet been planted largely, mention may be made of Magnolia
hypoleuca, which attains noble proportions, but does not produce its
handsome flowers freely until it has attained a large size; the Japanese
Horse-chestnut (^Esculus turbinata); the elegant Styrax japonicum;
Betula Maximowiczi, a handsome Beech remarkable for its large leaves
and yellow bark; Quercus acuta, Q. glabra latifolia, two Evergreen Oaks
of merit. Then there is Daphniphyllum glaucescens, one of the most
handsome of evergreen shrubs, and Vitis Thunbergi, which surpasses in
brilliancy of colouring V. Coignetice, long so popular for clothing trellises,
wall spaces, and tall pillars.

With a fuller knowledge of the distinctive characteristics of the
many beautiful trees, shrubs, &c., that had been introduced from Japan,
and the increased facilities for becoming acquainted with the various
phases of garden design that had long found favour in that country, it
is not surprising that a strong desire should have been felt by many
owners of gardens within the British Isles to create gardens more or less
in accordance with Japanese ideas. Practical expression has in numerous
instances been given to this desire, and, as might have been expected, with
varying results. Where the principles governing the making of gardens
on the lines followed by the Japanese landscape gardeners have been
acted upon as closely as circumstances would permit, the result has been
a distinct, interesting, and pleasing addition to the pleasure grounds. On
the other hand, where but scant attention was given to principles, the
results have not been altogether satisfactory.

The Japanese garden, as we understand the term, is not a swamp, as
suggested by some of the gardens that have come under our notice.
Neither is it a lake surrounded by an irregular belt of trees and shrubs

JAPANESE GARDENING

TWO VIEWS OF JAPANESE GARDENS ERECTED AT LONDON EXHIBITIONS
(Jas. Carter & Co.)

General Aspects of Commercial Gardening 17

and a winding walk, with, it may be, a bridge or stepping stones to cross
it at the narrowest part. The Japanese garden does not consist of one
or two features, but of many, and one of the distinguishing characteristics
of the Japanese landscape gardener is the skill with which he combines
the features of, it may be, a whole countryside, in an area of quite
moderate dimensions. Another attribute of his skill is the success
that is achieved in maintaining the relative proportions of the several
features, and also of the trees and shrubs with which the garden
is embellished. In accomplishing this important object he has in many
instances to use trees, ornaments, &c., of so small a size as to suggest to
the Western mind that the garden is intended as a model on a reduced
scale rather than for the enjoyment of the owner.

The garden in Japan is regarded from a somewhat different stand-
point from that which we consider it in this country. Here, to state
the case generally, we provide a garden adapted to the requirements of
the plants in which the owner is specially interested, with such embellish-
ments as may be considered necessary; to the Japanese, plants primarily
exist for the assistance they are able to render in the production of artistic
effects, and are utilized accordingly. One of the principal rules governing
the work of the landscape gardener in Japan is to follow nature as far
as is practicable, and to arrange the arborescent and other forms of plant
life in their natural associations. That is to say, plants which in a state
of nature have their home on the mountain side are not to be brought
down to those parts of the garden which represent 'the lowlands, and,
it may be, used in the formation of a flowery fringe to running stream
or silent pool. In like manner the plants that luxuriate in the moist
conditions that obtain at the lakeside are not used in the clothing of
the side of a hill or mimic mountain. The Japanese garden artist would
appear to give ready adherence to this rule, for he can readily include
in any given design the characteristic features of any given portion of
the native landscape.

Another rule of some importance is to avoid as far as practicable the
planting of deciduous trees, with a few exceptions, in the more prominent
positions of the garden. The exceptions are deciduous trees remarkable
for the beauty of their flowers, such as the Cherries and Plums, which
are not only immensely attractive when yielding their wealth of flowers,
but are great favourites with the Japanese. If it is intended to plant
a tree near the end of a bridge, one should be selected which will spread
its branches over it, and cast a shadow on the water. It is not considered
in accordance with the canons of garden-making to show the whole of
the volume of water tumbling over rocks, and therefore it is enjoined
that in selecting a tree for planting alongside a cascade that it will
throw its branches partly over the rushing water.

Shade-giving trees are considered the most suitable for planting near
seats and tea houses, and Pines are the most generally selected for the
purpose. Much the same rule applies to the planting of trees by the

VOL. I. 2

is Commercial Gardening

side of ponds and other small water areas, the object being to obtain a
cool retreat during the summer's heat. The selection of positions for
trees in the gardens is considered by the Japanese authorities as a matter
of much importance, and they feel, as do those in this country who have
had experience in such work, that when trees are planted without the
exercise of sufficient judgment the desired effect is lost.

For a long period Pines were the favourite garden trees, and they were
trained to form round heads or to some quaint shape to give a distinctive
appearance to the spot in which they were placed. Of late years Western
ideas would appear to have had some influence upon the Japanese, for
within the past decade or so trees more or less natural in growth have
come into favour, and the trees with formal heads or contorted branches
are no longer fashionable.

The Japanese Maples, of which there are now so many beautiful forms
in cultivation, are not always a complete success in British gardens, and
this is due in many instances to a failure to plant them in positions most
favourable to their full development. The Japanese, having a full know-
ledge of the elegance that characterizes the habit of these trees when
growing under natural conditions, and abundant opportunities for enjoying
the glorious colour effects produced by their leaves when the breath of
autumn has passed over them, freely use them in the creation of garden
scenery. They by no means limit their selection to the kinds that do
not take on their rich colouring until the summer months have run their
course, but group with freedom the many fine forms of Acer palmatum
that in the diversity in the form and colour of their leaves afford a rare
opportunity for the garden artist to produce colour effects of the most
beautiful description, extending from within a short time of the bursting
of the buds to the fall of the leaf. These Maples are of much value in
gardens, whatever may be their design, and particularly in those of small
size; and although the demand for them continues to be great, there is
room for an acceleration in the rate at which they are being planted.

The free use of stone in the making of Japanese gardens is a point
of much interest, and while it may not be regarded as of so much im-
portance as the trees with which the garden is furnished, sufficient care
and attention are bestowed upon its selection to ensure every piece being
suited to the position in which it is to be placed. Especially noteworthy,
also, are the stone ornaments, of which the lanterns of stone are the
most important. These lanterns may be of granite, sandstone, or lime-
stone, and they take us far back into the distant past. For many centuries
they were exclusively associated with the temples that have a prominent
place in many parts of the country; but in the course of the development
of the landscape art some of the leading exponents conceived the idea of
using them in the adornment of the garden, and within a comparatively
short period their use became general.

Stone lanterns are no longer confined to Japan, for larger numbers are
annually imported, and many are the British gardens wherein several may

General Aspects of Commercial Gardening 19

be found. These lanterns differ considerably in design, and there is no
difficulty in selecting one that is well suited to the position it is to occupy,
whether it be by the waterside, alongside the bridge of stone, or for forming
a contrast to the brilliant colouring of the Azaleas or Irises, or the feathery
growths of Bamboos and tall-growing grasses. It is one of the canons of
the landscapist's art that these lanterns should be partly sheltered by trees,
either at the back or front.

In the water scenery that usually has a place in Japanese gardens
stepping stones are freely used, and form walks that wind through the
water garden and afford an opportunity for closely inspecting the Water
Lilies, the Lotus, the Irises, and the many other beautiful plants that
thrive in or near water. In some of the more extensive gardens bridges
of stone are provided for crossing the deeper waters, but the quaint semi-
circular bridges of wood which are now so well known are the most
general. The tea house is an essential feature of the Japanese garden,
and it may be mentioned that it is usually so constructed of Bamboos or
light strips of wood as to allow the air to circulate freely through it, and
it is assigned a position on the bank of a lake or pond, on a prominent
island, or in some other part of the garden where scenes more or less
beautiful can be readily seen.

An essential feature of the Japanese garden is its bamboo framework
clothed with the Wistaria, which in its season gives a wealth of the long
pendent racemes of blue or white flowers; and even if the Wistarias fall
short of the magnificent specimens at Kameido, a suburb of the city of
Tokio, they afford displays of wondrous beauty. What has been accom-
plished in Japan in the cultivation of Wistarias may be done in Japanese
or indeed any other gardens in this country. Not less noteworthy for
their value in beautifying the gardens of Japan are the double-flowered
Cherries, such as Prunus pseudo-cerasus fl.pl., which are planted freely,
and annually produce delightful displays. All the best forms that are
grown in Japan are in trade collections in this country, and it is
much to be desired that with the increased attention that is now given
to Japanese gardens they may "be planted by the dozen, instead of singly,
as is now usually the case. [o. O.]

SECTION II
The Science of Plant Growin

i. SIMPLE AND COMPLEX CELL LIFE

The successful cultivation of plants requires a close familiarity with
their likes and dislikes, a knowledge of the conditions of their existence,
and how to meet those conditions to the best advantage of the culti-
vator; for the requirements of man are not always identical with the
objects of the plants themselves. By dint of practice alone and close
application to the art for a series of years one may become sufficiently
expert to grow a limited number of kinds to great perfection, but the
field for experiment and improvement is boundless in the domain of
gardening. Not merely are there plants, flowers, fruits, and vegetables
with which one is familiar, but new ones are constantly arising, differing
in some respect from those that preceded them; and hundreds of others,
whose cultivation is an undetermined quantity, or may have been known
to the successful growers of bygone times and since forgotten, may be
placed under the charge of the gardener. The traditions of the past have
not merely to be maintained, but the gardeners of the present have to con-
tinue the forward march of improvement, by introducing better methods
of cultivation wherever opportunity occurs, by improving the fruits,
flowers, and vegetables already under cultivation, and originating new
ones by the various means and methods at command. The field of
enquiry is wide enough for every class of worker, and the practical culti-
vator may avail himself of the assistance at his disposal from various
sources by acquiring a knowledge of the structure and nature of plants,
just sufficient to enable him to comprehend the meaning of the information
imparted by the more scientific worker.

Simple Cell Life. A good conception of plant life in its simplest
form may be obtained by an examination and study of some of the
lower organisms, such as the green scum to be seen on damp walls or
the trunks of trees, where the water runs down during rain. If a minute
particle of this green matter (Protococcus viridis) is put in a drop of
water and placed under a high power of the microscope, it will be seen
to consist of numerous tiny green bodies of various sizes, invested by

The Science of Plant Growing 21

a colourless envelope or cell wall. Each individual constitutes a com-
plete plant. The interior is filled with a particle of granular, jelly-like
matter, stained green. This jelly-like substance has been named proto-
plasm, and, as it is present in all living plants and animals, it is con-
sidered the seat of life. It is the essential part of the plant, as we shall
see presently. When any of the cells has reached full size, it divides
into two equal parts, which become separate individuals, and repeat
the history of their parent by feeding, growing, and again dividing.
Those who would see- this process must needs burn the midnight oil,
for one-celled green plants manufacture food from the atmosphere by
day in preparation for dividing by night. Rain brings down many of
these plants from the roof-gutters of the house, and if a drop of watei
from the water butt is examined in summer or other suitable time it
will be found to contain more or less numerous organisms, some con-
sisting of a particle of green jelly, without the cell wall, and larger
ones with an investing wall, but both sizes moving about rapidly. The
movement is due to the rapid vibration of two slender thread-like portions
of the protoplasm, without colour, and therefore invisible till something
is put in the water to bring the organisms to a state of rest. After
a time they lose these filaments, and become surrounded by a cell wall,
like those on the damp wall. From the damp wall, or from the water
in the butt, these lowly plants absorb their food, or rather the raw
materials from which they manufacture it. Already we can see that
the cell wall can be dispensed with as so much dead matter, while the
naked protoplasm is still termed a cell, and is equally an individual plant.

The Yeast Plant (Saccharomyces cerevisice), such as is used by the
brewer, if put in any clear liquid containing suitable food (malt, for
instance), the liquid, if stood in a warm place for some hours, will
become cloudy or muddy, this being due to the rapid multiplication
of the Yeast Plant. The temperature of the fermenting liquid is raised
as a result of the chemical changes being brought about in the con-
stitution of the liquid by the Yeast Plant. If a drop is examined under
the microscope, the plant is seen to be oval, smaller than the Protococcus,
but without the green colouring pigment of that, showing that it belongs
to the great group of Fungi. It is also rapidly multiplying by budding
at one end. The tiny protuberance or offset grows to nearly the size of
its parent, and drops away as a new individual.

The "clubbing" of turnips, cabbages, cauliflower, and other members
of the Crucifer family is due to another fungus, which lives within the
roots during summer and other mild periods, causing great swellings to
arise. At this period each individual multiplies rapidly, and rests
enclosed in a cell wall of its own during winter; but with a rise of
temperature in spring the protoplasm quits the cells and unites in
a jelly-like mass, which moves through or over damp soil in quest of
fresh plants to attack.

From these three plants it will be seen that the protoplasm possesses

Commercial Gardening

certain properties. They can absorb food materials, manufacture the food,
breathe, give off certain ingredients as waste products, reproduce them-
selves, and in two cases are possessed of motion, the
capability of which resides in the protoplasm itself
(fig. 2). The Protococcus can manufacture its own food
from raw materials, by reason of the presence of green
colouring matter under the influence of light. The
Yeast Plant must be supplied with malt, grapes (in
wine-making), or some other food already in an organ-
ized form. As the club-root fungus (Plasmodiophora
brassicai) is also colourless, it must have organized food,
and, as it feeds upon living plants, it is a parasite.
All of them absorb oxygen to give them energy, and
as it combines with some of their substance, carbon
dioxide is given off. The process is equivalent to
breathing or respiration, as in animals, and is abso-
lutely essential to all living things.

2. STRUCTURE OF THE HIGHER
PLANTS

Fig. 2. Protoplasm The Growth of a Cell. The three plants already

SZSSiSSlio* considered consist of a single cell, varying chiefly in
of Arrows size during their lifetime. Other plants, in an as-

cending scale of organization, consist of more or less
numerous cells united in a variety of ways to form the plant body, either
in the form of filaments, or flat plates of cells, as in freshwater or marine
algae. The larger seaweeds form a tissue resembling stem and leaves, but
a true stem and leaves are first met with in Mosses and Sphagnum. The
Ferns are still more . highly organized, by having true roots, stems, and
leaves. The flowering plants are the most highly organized, and gardeners
are chiefly concerned with them. The tiny Duckweeds, which cover still
ponds in summer, are flowering plants of very exceptional structure, for
they consist merely of a small mass of green cells, with one or more
root hairs from the under side. The smallest of all (Wolffia arrhiza)
has not even a root hair. The tallest tree and the smallest plant,
amongst flowering subjects, consist alike of an aggregation of cells, built
up in some definite form, according to the kind.

A full knowledge of plants may be obtained by a study of proto-
plasm and its protective covering the cell wall together with their
behaviour when acted upon by light, heat, air, and moisture. A very
young cell may be taken from the leaf of an apple tree, when beginning
to unfold. It may be oval or nearly round. Under a high power of the
microscope the wall appears double, but each individual has its own
wall, and the other is the wall of the cells that abut on the one under

The Science of Plant Growing

examination. The interior at first is entirely filled with protoplasm, in
the centre of which is a denser, oval body the nucleus consisting of
a granular groundwork of protoplasm, denser at its margin, and having
a fibrillar network of granules embedded in it. The nucleus plays a very
important part in the division of full-grown cells. As the cell increases
in size, cavities make their appearance in the protoplasm, filled with cell
sap and air, and this continues till the cavities unite and the protoplasm
can only form a lining to the wall, with a few
bridles connecting it with the layer of proto-
plasm surrounding the nucleus in the centre
(fig. 3). Streaming movements of the proto-
plasm may often be observed in the living
cells of various plants (the direction being indi-
cated by arrows in fig. 2). The large granules
to be seen embedded in the protoplasm are

chlorophyll or leaf green. The further history of this cell depends on
whether the tissue requires more cells or not for its full development.
If it does, then the nucleus elongates into spindle form, the protoplasm
forms a mass at each end of the spindle, the two masses being joined
by threads. A layer of protoplasm (the cell plate) then extends across
the cell from wall to wall, and from this layer a new partition is formed
simultaneously and continuously. Thus two cells are formed. The
common partition later on splits into two, so that each daughter cell has

Fig. 3. Isolated Cells (1 and 2)
with and (3) without Nuclei
highly magnified

123

Fig. 4. Changes in the Protoplasm of the Cell Nucleus during its Division

1, The Nuclear Fibrils distributed through the whole Nucleus. 2, The broken-up Nuclear Fibrils
arranged as the Nuclear Plate. 3, The elements of the plate separating from one another. 4, The same
elements forming two skeins at the poles of the Spindle. (After Guignard.) Very highly magnified.

its own complete wall and a half of the original nucleus (fig. 4). If the
full-grown cell does not intend to divide, the remainder of the protoplasm
is used up in thickening the walls, or is drafted away into younger and
growing cells. The empty cell is now dead for all time coming, though
it may exist for a thousand years or more, if it forms part of the stem
of a giant Sequoia gigantea of California. The cell wall at first consists
of cellulose, a substance closely allied to starch and sugar, all three being
made up of the chemical elements carbon, hydrogen, and oxygen, in
different combinations, and all becoming black when burned.

2 4

Commercial Gardening

Fig. 5. Section across
Wood Cells, showing concen-
tric layers of woody matter
surrounding a central cavity
Scolopendrium

Fig. 6. Elder Pith,
consisting of aggrega-
tions of Cells magni-
fied

Changes in Cell Walls. Although the cells of the higher plants
may be all very much alike when they begin life, they vary immensely
in size, shape, and structure by the time they reach
full development, their ultimate construction being
dependent upon the functions they have to perform
for the wellbeing of the plant. The most common
change is the thickening of the cell wall internally,
by successive layers of cellulose, till
the internal cavity is nearly filled
up, and the cellulose gets converted
into wood (fig. 5). The cells of the
pith remain thin -walled (fig. 6).
Those on the outside of the trunk
of the Cork tree, Elm, Ash, &c., get
thickened like those of the wood;
but in this case the material is con-
verted into cork, which is very light
and almost impermeable by water.

A thin layer on the outer face of all leathery leaves, like those of the India
Rubber and Palms, forms the cuticle, and is also of the nature of cork.

Various Forms of Cells. With the exception of lowly plants like

the duckweeds, the flowering plants gene-
rally furnish examples of cells of great
variety of form and length. Those which
become thread-like, but thickened inter-
nally, are termed wood cells (fig. 7), but
wood fibres when they become pointed at
the ends, with the thin portions spliced
or overlapping, so as to form continuous
masses of wood (fig. 7). The thickening
is by no means always uniform, for small
spots are left unthickened in pinewood,
and such are known as pitted wood cells
(fig. 7). The thickening may take the
form of single or double spiral bands in
the stems of Melons and Cucumbers (fig.
8), ring-like bands, or a mixture of an-
nular and spiral ones (fig. 8). In ferns
the bands unite in the form of a ladder.
These elongated cells may be placed end
to end and the partitions broken down,
thus forming continuous vessels, like a hose pipe, for the rapid convey-
ance of liquids. Sieve tubes are formed in the inner bark of stems by
the dividing plates of vessels becoming perforated by small openings.
Plants with a milky juice, like the Lettuce, Dandelion, and India Rubber }
have cells which join in a variety of ways and break down the inter-

Tracheids

Fibres
Fig. 7.-Wood Cells

The Science of Plant Growing

vening partitions, becoming continuous and forming what is known as
laticiferous tissue (fig. 8).

Spiral and Celandine Laticiferous
Annular Vessels Tissue

Dandelion Laticiferous
Tissue

Plant Tissues. All the above forms of cells and many more unite
in certain definite relations to one another, forming a tissue (fig. 9). Most
flowering plants, Ferns, Lycopods, and
Selaginellas have representatives of
various forms of cells, wood fibres, and
vessels in their tissues, and are spoken
of as fibro-vascular plants, and consti-
tute the most highly developed members
of the vegetable kingdom. A mushroom
is not a fibro-vascular plant, as it is
made up entirely of branching threads
of thin-walled cells.

Uses of Different Cells. The
thickened outer cells of leaves and
young stems are of a protective nature,
so far as the cuticle is concerned, while
the interior is thickened to impart
strength. Wood fibres give rigidity to
the stems of herbaceous plants and in
a greater degree to trees, which have
the greatest number of them; and they,
in conjunction with the continuous tubes
or vessels, serve for the rapid convey-
ance of liquids, containing ingredients
of plant food, as well as elaborated food
being carried to the points of growth or to be stored. The laticiferous

Fig. 9. Cut illustrating various tissues. To
the left Spiral Vessels, followed by long Conduct-
ing Cells. These are succeeded by Cellular Tissue
or Parenchyma. In some of the square cells are
Crystals of Oxalate of Lime. In the longer cells
are groups of Needle-like Crystals called Raphides.
To the extreme right are Pitted Cells.

26 Commercial Gardening

tissue is more obscure, but some of the contents are of the nature of stored
food. Some cells are set apart entirely for the purpose of marrying and
reproducing the plant. The other cells have their respective duties, and
have neither time nor opportunity for this. [j. F.]

3. PLANTS OF DISTINCTIVE CHARACTER

Plants with Chlorophyll. Most plants with which the gardener has
to deal contain chlorophyll or leaf green in their leaves and the super-
ficial tissues of their stems, at least during the first year. It consists of
a green pigment colouring the large granules that develop it and lie
embedded in the protoplasm, but are capable of shifting their position if
the light is too strong for them. These green granules, under the influence
of sunlight and electric light, are the agents by which all raw food materials
are chemically changed in character and converted into organized material
suitable for building up the plant body and enabling it to store food for
future use, or to provide for its offspring. The light must be accompanied
by the other necessaries of plant life, such as heat, air, and moisture.
Green plants are thus able to manufacture their own food and lead an
independent existence. Crotons, Dracaenas, Coleus, and other plants with
highly coloured leaves have chlorophyll in their tissues, but this is obscured
by the presence of other colouring matters, diffused through the cell sap.

Plants without Chlorophyll. Amongst flowering plants many species,
including the Broomrape (Orobanche) that lives attached to the roots of
Clover, and the Dodders (Cuscuta) that live on Clover, Nettles, Hop, and
other wild plants, have no chlorophyll in their tissues, and cannot manu-
facture their own food. They must needs attach themselves to the roots
or stems of certain green plants and absorb their food in an organized
form, thus robbing and injuring their hosts to a greater or less extent.
The Broomrape sometimes attaches itself to the roots of Pelargoniums in
pots, and one of them, kept under observation by the writer, was allowed
to flower, The result was that the Pelargonium was stunted in growth
and failed to recover itself, even after the parasite was removed. Such
plants are termed parasites, because they absorb their food from living
plants. The great group of fungi have no chlorophyll in their tissues,
and many of them are parasites, like the Club-root fungus of Cabbages,
the Mildew and Rust of Roses and Chrysanthemums, the Rust and Brand
of Wheat, and many other cultivated plants. A large number of them
are very minute, one-celled, and capable of producing diseases in plants,
man, and other animals. In these two latter cases they owe their existence
indirectly to green plants as the first and only manufacturers of organic
food. On the other hand, many fungi are harmless, because they live upon
dead and decaying plants and animals, and are termed saprophytes. The
Mushroom is one of them, and lives upon fermenting manures and other
decaying matter. So far it is the only plant without chlorophyll, that is

The Science of Plant Growing

of any importance to cultivators in this country. All fertile soils swarm
with minute, one-celled fungi or microbes, living upon dead matter and
converting much of it into a soluble form, suitable as food for green plants.
In a word, they are the agents alike of decay and fertility, preparing the
soil, the manure, and leaf heaps for the use of the higher plants.

Lichens are composite plants, consisting of a fungus and a small green
alga, working in co-partnership for their mutual benefit. Even some of
the higher plants, including several forest trees, have messmates or co-
operators amongst fungi, large enough to be seen by the naked eye
(fig. 10). The fungi closely invest the fibrous ends of the roots and absorb
the food they require from the trees. On the other hand, some of the
waste products of the fungi
are required by the trees to V^M* 1

complete their bill of fare.
It is not yet determined to
what extent this co-operation
prevails among cultivated
plants, but some plants diffi-
cult to cultivate may really
require this kind of assist-
ance. It is well known that
Rhododendrons and other
plants belonging to the same
family like a peaty soil and
hate lime in any form. In
all probability the lime de-
stroys the microbes in the
peat that are essential to the
welfare of the Rhododen-
drons.

Desert Plants. Echeverias, Crassulas, and Aloes, from South Africa
and Mexico, have fleshy stems and leaves. Cacti, including Epiphyllums
from Brazil, Mamillarias and Phyllocacti, from Mexico and other warm
and dry parts of America, are also fleshy but have dispensed with leaves
to economize their liquids. In their native habitats they get very little
rain, and make a point of storing up what they do get, while their struc-
ture is such as to prevent the liquids from escaping too freely. Under
cultivation many of them enjoy liberal treatment in summer, when the
temperature is high and they are making their growth, but they must
be kept relatively dry in winter when at rest and the light is bad. With
few exceptions they like a relatively high temperature even in winter.
They cannot give off moisture like thin-leaved, green plants, consequently
water must be withheld almost entirely during winter, otherwise they
would decay wholesale. A gardener can readily diagnose a plant of this
character, without knowing its name or from what country it comes, and
give it the proper treatment accordingly.

Fig. 10. Illustration of Co-partnership or Symbiosis

1, Roots of the White Poplar with Myeelial covering. 2, Tip
of a Root of the Beech with closely adherent Myeelial covering ;
x 100 (after Frank). In these cases the Myeelial threads on
the roots are of fungous origin, deriving nourishment from the
roots on which they grow, but at the same time supplying
food material to the roots.

28 Commercial Gardening

Other plants of dry countries produce hard and wiry leaves, like the
Grass tree of Australia (Xanthorrhoea), and must likewise be kept on the
dry side during winter. The Rushes (Juncus) of our marshes and river
banks belong to the same family, but their stems are very largely made
up of loose, spongy tissue, surrounded by a thin layer of more solid
structure, almost like a skin. They are therefore capable of giving off
large quantities of water at any time when circumstances require it.
Some plants of dry climates and arid soils and situations clothe themselves
with a more or less dense coating of hairs; and in proportion to the density
of this covering must they be kept dry in winter, otherwise they would
sooner or later get into an unhealthy condition and ultimately perish. The
roots are usually the first to suffer from an excess of moisture, but the
functions of the leaves and other parts also get deranged. The common
Stock, in a wild state, inhabits dry chalk cliffs, and all parts of the stems,
leaves and calyx are densely covered with star -shaped, branching hairs.
Seedlings under cultivation are extremely liable to damp off while quite
young, if kept too close and moist in the seed pans or boxes. The exces-
sive moisture renders them liable to attack by the " damping-off" fungus
(Pythium debaryanum). It is not usually regarded as a desert plant, but
it serves to explain a similar difficulty when brought under cultivation
from its dry, wild habitats.

Clammy-leaved Plants. At first sight these may not seem peculiar,
when Petunias and Salpiglossis are mentioned, for there are many other
examples under cultivation. They are plants, however, which delight in
sunshine and flower best in dry weather. The writer has seen Pelar-
goniums and other plants remain stunted and lose their foliage in a dry
garden on the chalk formation, in a droughty summer, while Petunias,
Gaillardias, and other clammy-leaved plants were the only flowering sub-
jects in the beds. While young and making growth they enjoy fairly
liberal watering, with a moist atmosphere, but to bloom freely they must
have plenty of light and air, and be kept dry overhead. The viscid hairs
with which they are covered enable them to recuperate themselves during
the night from the deposit of dew in the open ground.

Insectivorous Plants. Many plants, whose root system is not well
developed, or which live in swampy places, where they have difficulty
in procuring a sufficiency of nitrogen in the usual way, have evolved
some peculiar contrivances for eking out the supply. The Sundews
(Drosera), Venus Fly-trap (Dionasa), Pitcher Plants (Nepenthes), (fig. 41).
Butterworts (Pinguicula), and Bladderworts (Utricularia), belong to this
class, and many of them are cultivated. By various means they manage
to capture and detain insects and other small creatures, which they
digest or dissolve, absorbing the nitrogen. The Sundew (fig. 11)
develops on the upper surface of its leaves numerous tentacles, each
terminated by a sticky gland. Flies alighting upon a leaf get held fast
by the viscid matter, while the other tentacles close upon their victim.
The protoplasm now forms a " ferment", and the liquid is spread over the

PERPETUAL CARNATIONS
i. Carola. 2. White Perfection. 3. Victory. 4. Enchantress

. (Half natural size)

The Science of Plant Growing 29

fly till dissolved, when the juices are reabsorbed. A stone or other object
would cause the infolding of the tentacles, but if such objects contain no
nitrogen the tentacles soon unfold, without having produced any chemical
changes in the protoplasm, thus proving that nitrogen was the element
of food required.

Climbing" Plants. The Convolvulus, Wistaria, and Scarlet Runner are

123 4

Fig. 11. To show contraction induced by the contact of insects. Tentacles on Leaf of Sun-dew (Drogera)

1, Glands at the extremity of a Tentacle; x 30. 2, Leaf with all its Tentacles inflexed towards the middle.
3, Leaf with half the Tentacles inflected over a captured insect. 4, Leaf with all the Tentacles extended.
2, 3, and 4x4.

examples of plants that climb by twining their stems round some support-
ing object. If the top or free end of a Scarlet Runner is observed at
different times during the day, after it has commenced to run, it will be
seen to be swinging round in a wide circle, and should it chance to touch
a stake, string, wire, or other support, it commences immediately to coil
tightly round the same and to make rapid progress. The stem is sensitive
to contact and this sensitiveness resides in the protoplasm, being one of
its properties. Scarlet Runners grown in the field without stakes often
twine round one another, but without proper support they never attain
the length of which they are capable, nor do they produce so heavy a
crop. The saving of labour and the extra cost of stakes are the chief
reasons for this method of culture. Sweet Peas, garden Peas, Cucumbers,
Melons, Vines, and others climb by special structures known as tendrils.
The leaf stalks of Clematis and Tropseolum twist round supporting objects
in a similar fashion, and they as well as tendrils are sensitive to contact.

[J. F.]

4. THE ROOT AND ITS WORK

The Primary Root. The first structure that emerges from the interior
of a germinating seed is the primary root or radicle, which goes perpen-
dicularly down into the earth. If the minute structure of the tip of this
is examined it will be seen to consist of very small square cells at and
behind the growing point (fig. 12). Around and in front of this is a layer
of brick -shaped, corky cells, most of which are empty and dead. This is

Commercial Gardening

the root cap, which is intended to protect the tender growing point as it
pushes its way amongst the particles of soil. The nature of a young root
may readily be seen by filling a punnet with light sandy soil and scatter-
ing some Mustard seed thinly over the top. Stand it in a warm, moist,
shady place for a few days till the seed germinates, and
then in a well-lighted position. From the sides of the
radicle numerous hairs arise, enter the soil in a horizontal

direction, and place themselves
in close contact with the par-
ticles of soil (figs. 13, 14, 15).
These are the root hairs, and
their function is to absorb
water containing food in solu-
tion. The interstices or spaces
between the particles of soil
are filled with air, or should be,
for land plants, but the par-
ticles themselves are covered
with a thin film of water, and this is all that the root hairs can absorb.
If the interspaces are filled with water, the soil is water-logged and the
radicle and root hairs cannot breathe, but soon get asphyxiated and perish.
The radicle does not absorb water at the tip but some way behind it, and
only while the outer walls remain quite thin. The root hairs continue

their work for a few days or
weeks, then die away and
leave no trace behind; but as
the radicle lengthens and sec-
ondary roots are formed, new
,^ % root hairs are continually

Fig. 12. Section through the Root
Tip of Pentstemon. The bowl-shaped
mass at the tip is the root cap; x 60.

Fig. 13. 1, Seedling
with the long absorp-
tive cells of its root
(" Boot Hairs ") with
sand attached. 2, The
same seedling: the sand
removed by washing

Fig. 14. Koot Tip of Pentstemon with Root Hairs penetrating
between the particles of soil ; xlO

fig. 15. Root Hairs or Absorptive
Cells of Pentstemon with adherent par-
ticles of earth

being produced, thus tapping fresh areas for food. In Dicotyledons
generally the primary root is permanent, and, if undisturbed, may attain
a great size and age in forest trees. From an early stage of growth it
commences to give off secondary roots which branch repeatedly, permeating
the soil in every direction with their finer ramifications or root fibres. In

The Science of Plant Growing 31

Monocotyledons, like Lilies, Daffodils, Onions, Palms, and Grasses, the
primary root soon ceases to lengthen or dies, but its place is taken by
numerous, secondary, and even adventitious, fibrous roots. Some of these
attain a considerable thickness in large Palms and Screw Pines (Pan-
danus), but in grasses they remain slender and fibrous (fig. 16).

Importance of Primary and Fibrous Roots. In
general terms roots serve to fix the plant in the soil. The
primary, descending root of forest trees is of considerable
importance to many of them, like the Oak, Elm, and Ash,
in preventing them from being overturned during gales
and hurricanes of wind. To gardeners it is of leading
importance in the case of such root crops as Carrots, Par-
snips, and Beet. Great care is taken in preparing the soil
to a considerable depth, and the seeds are sown where the
plants are to grow till they reach maturity. No trans-
planting is permissible. If the primary root or radicle were
broken, a shapely taproot would be impossible. All of
them could be transplanted with the greatest facility,
and, with care, almost every root would grow, but they Grafs -Fibrous d Root
would be short, stumpy, forked, misshapen, unsaleable, and
useless except for cattle. A deeply worked and well -pulverized soil is
necessary to enable the radicle to descend perpendicularly without twist-
ing or bending between stones and hard lumps; and if well manured for
some previous crop, the radicle and slender, lateral fibres will be well able
to forage for the requirements of a large and shapely root. It is quite
different in the case of Cabbages, Apple, Pear, and other fruit trees,
because transplanting multiplies the number of fibrous, feeding or absorb-
ing roots. The more fibres upon the roots of Cabbages, Onions, and the
like, the sooner they get established in their permanent positions when
transplanted. Taproots are undesirable in fruit trees, because they often
get down into uncongenial subsoils, while plenty of fibrous roots near the
surface induces early fruitfulness and permits of feeding.

Relation of Soil to Roots. As already observed above, the root hairs
of plants apply themselves very closely to the particles of soil, in order to
absorb the thin film of water adhering to them. This film contains plant
food in a state of solution, and in greater quantity than in the root hairs
themselves, but at the same time the solution is very dilute and the root
hairs have to absorb a much greater quantity of water than is actually
required by the plant in order to get a sufficiency of food. The nature
of a soil bears a definite relation to its fertility. A sandy soil, being made
up of relatively large particles, can hold only a very limited quantity of
water, because the spaces between the particles are large and filled with
air. If manure is applied it rapidly decays and much of the plant food
in it is washed away into the drainage by rain. If liquid manure is
applied, most of it runs away. On the other hand, the particles of a clay
soil are much finer, hold more water and plant food, either in solid or

32 Commercial Gardening

liquid form. If some of the latter is poured on a clay soil, it can abstract
ammonia, free potash, phosphoric acid, and various salts containing plant
food and hold them till they are absorbed by plants. All clay soils, if
not originally fertile, can readily be made so by artificial means, and it
only remains for the cultivator to make them sufficiently porous by good
tilth to enable the roots of cultivated plants to penetrate freely and collect
the food stored.

Water and Air Roots. While the roots of land plants can only absorb
the film of water adhering to the particles of soil, the roots of water plants
are able to absorb the free water with which they are surrounded. They
are greatly elongated, much more branched than those of a land plant,
and thin -walled, without cuticle or root hairs on their surface. A land
plant may produce water roots, as when Hyacinths are grown in glasses

of water. Another good instance in nature may
often be seen where the roots of trees penetrate
tile drains and actually choke them up. If the
roots of a land plant are immersed in a vessel of
water they continue to absorb water for a time, but
soon develop true water roots and the earlier or
original fibres die. They get their food and air
dissolved in the water surrounding them. One
peculiar form of air root may be seen in Orchids.
The root is surrounded by a membrane of cells,
several layers deep, more or less thickened, per-
forated with holes, and filled with air. They ab-

17. -Dahlia-Tuberous Root sorb rain containing plant food in solution, and
deposited at first in the form of dust on or near

the root. If such roots develop on the outside of a flower pot or basket
they must not afterwards be buried either in soil or Sphagnum. The
writer has seen a fine batch of Moth Orchids (Phaleenopsis) killed by
placing the small baskets inside larger ones and filling the space between
with Sphagnum. In many Aroids that produce aerial roots the surface
is loose and spongy and more or less densely covered with root hairs
which absorb moisture from the air.

Tuberous Roots. The primary and secondary roots of the Dahlia
become greatly swollen and spindle-shaped (fig. 17). The thickened
portion is intended for the storage of reserve material with which to
make a good start the following season in the production of the flower
stem. The material stored is inulin. The base of the stem and the upper
part of the root of the Turnip becomes greatly thickened and tuber-like,
storing starch for the requirements of the flower stem in the second
season. In the case of the fleshy, thickened taproots already mentioned,
the Carrot and Parsnip store starch for the same purpose as the Turnip,
and, all being good for food, they are cultivated for this special purpose
by man. The same applies to Beet, which stores a sugar very like cane
sugar.

The Science of Plant Growing 33

Work of the Roots. In summarizing the above remarks it may be
said that roots fix the plant in the soil, commence to absorb watery solu-
tions of plant food at a very early stage; they breathe, and, in the case
of land plants, must be grown in well-drained soils, while they are modified
in certain plants to perform similar functions in water, or air, and have
become fleshy and constitute a storehouse of reserve food in the cases men-
tioned. Some substances of plant food are soluble in pure water; others
are rendered soluble by the presence of carbon dioxide, lime, and other
ingredients in the soil. The root hairs and the younger slender fibres of
the root are able to dissolve other substances. Their cell walls are actually
permeated with acid sap, and this dissolves substances with which they
come in close contact. If a small slab of polished marble is placed in the
bottom of a flower pot in which a Sunflower, Broad Bean, or Scarlet
Runner is grown during the season, and examined in autumn, it will be
found that the roots have left their exact impression by eating away the
polished surface. If the ingredients of plant food absorbed were to remain
unchanged inside the root hairs the sap would soon be of the same density
as the watery solution outside the membranous wall, and the inward cur-
rent would cease; but their chemical nature is continually being changed
in one or other part of the plant, and the cells abutting on those having
the root hairs absorb the food from the latter, and so on in succession, until
it is carried into the vascular tissue of the root, and thence into the stem.
This absorption goes on continually night and day, so long as the con-
ditions are favourable. The result is that a current of sap is being pushed
into the interior of the plant by the activity of the roots, and is known
as "root pressure", some of the effects of which will be discussed in the
chapters on the stem and the leaf. Energy is required by the roots in
order to perform all this work, and that is obtained by the absorption of
oxygen from the air in the process of breathing. For this reason alone,
trees and shrubs should not be planted too deeply, nor should soil be
heaped over the surface, where such are already established. We have
frequent evidence of large trees being killed outright in a few weeks by
the deposition of 3 to 5 ft. of muddy soil or clay over their roots, which
cannot breathe nor perform any other function for want of air. Badly
drained soils have similarly evil effects. When the soil in flower pots is
over-watered, or the drainage hole gets stopped up by worms, the roots
cannot get sufficient air, and their functions become deranged, or they die.

The Food absorbed by Roots. Of the ten elements of plant food
that are absolutely essential, all of them, except carbon and a small quan-
tity of nitrogen, are absorbed by the roots. They are oxygen (the free
oxygen of the air is used only in breathing), hydrogen, nitrogen, sulphur,
phosphorus, potash, calcium, magnesium, and iron. They are not absorbed
in this simple form, but in various combinations termed salts (such as
nitrates), acids, &c. Oxygen and hydrogen are absorbed in the form of
water; nitrogen in the form of ammonia and nitrates; sulphur as sulphates;
phosphorus as phosphates; potash and lime in combination with sulphur,
VOL. I. 3

Commercial Gardening

phosphorus, nitrates, &c.; and iron in a variety of compounds. Most of
the above are present in sufficient quantity in soils generally, and when
land requires manuring, nitrogen, phosphorus, and potash are usually most
deficient. Lime is occasionally deficient, and is useful for a variety of
purposes. Except in the case of Leguminous crops, such as Peas, Broad
Beans, Dwarf Beans, and Scarlet Runners, nitrogen is always necessary
unless the soil is very fertile. Leguminous plants have bacteria in small
nodules upon their roots, and these bacteria are capable of fixing the free
nitrogen of the air. Farmyard manures are very valuable in light soils
by increasing their power of holding water, independently of the plant
food they contain.

Contractile Roots. Apart from the functions already described, a
large number of bulbous plants are provided with roots which have the

Fig. 18. Seedling Plant of Gourd (Cucurbito Pepo) with Radicle, Caulicle, and opposite Cotyledons.
Liberation of the Cotyledons from the cavity of the Seed or Fruit Husk, showing in the central figures
the little peg or radicle that serves to fix the seedling.

power of contracting at certain periods, and thus pull down the bulbs or
corms deeper into the soil. These roots are known as " contractile ". They
are generally thicker and fleshier than the more fibrous feeding roots, and
are recognized by the transverse wrinkles or rings upon them. The young
or new corms of Gladiolus and Crocus, and the young bulbs of many Liliums
and other bulbous plants, are all provided with such roots. In the case of
seedlings, Dr. Scott says, in his Structural Botany, that the young bulb
"is gradually drawn down year by year owing to the shortening of the
adventitious roots. As the end of the root attaches itself firmly to the
soil, the effect of the contraction is to exert a downward pull on the bulb.
The upper part of the root is alone capable of contraction, and is much
thicker than the rest. The inner cortex is the actively contractile tissue;
as it contracts, the external layers are thrown into transverse wrinkles.

The Science of Plant Growing

New roots of this kind are formed each year, until the bulb has reached
its normal depth." [j. F.]

5. THE STEM AND ITS FUNCTIONS

The Seedling" Stem. Almost any seedling will serve to show the
origin and development of the stem from an early stage of its growth.

Fig. 19. 1, 2, Seedling of Nasturtium (Tropceolwn majus). 3, 4, Seedling of Water Chestnut (Trapa
jiatam) with section of seed. 6, 6, Seedling of Austrian Oak (Quercus austriaca). 7, 8, 9, 10, Stages in
the germination and growth of Date Palm (Phoenix dactylifera) with sections. 11, 12, 13, Seed and
germination of same of Reed Mace (Typha Shuttlewwthi). 14, 15, Seedling of Sedge (Carex mtlgaris).
1-8 nat. size ; 9, 10, x 8 ; 11-13, x 4 ; 14, 15, x 6.

It forms part of the embryo, while still in the seed. A Stock, China Aster,
Cabbage, or Gourd seedling (fig. 18) will serve the purpose. Between the
ground and the seed leaves the short, upright portion is the first visible
part of the stern, to which various names have been given, including

36 Commercial Gardening

cauiicle, which means little stem. Structurally it is mado up of cells,
fibres, and vessels, built up in the form of tissue characteristic of a stem.
Its functions are to hold up the seed leaves to the light and supply them
with water and food materials. Between the seed leaves the first bud of
the plant, known as the plumule, will be noticed. It is really the apex
of the young stem, covered with the rudiments of the first true or rough
leaves. Many variations are met with amongst seedlings. For instance,
in the Scarlet Runner, Broad Bean, and Oak the seed leaves remain in
the seed, below-ground, during and after germination. In these cases the
cauiicle remains very short, the seed leaves do not make their appearance,
and the plumule is the first part to rise above ground. The cauiicle under-
goes modification in other ways in certain plants. The upper portion of
the tuberous swelling of the Turnip and Radish consists of the cauiicle,
enlarged and fleshy, to serve as a store for reserve food.

The Growth and Thickening- of the Stem. As the plumule grows
and develops into a stem of some length in the Stock or China Aster, it
is seen to be self-supporting, because the thickness and woody matter in
the interior is proportionate to the height. The leaves of the Cabbage
are much larger, and the stem becomes greatly thickened to support them.
The stem of the Gourd becomes enormously lengthened in proportion to
its thickness, but has to lie on the ground unless supported. If the stem
of any of these plants is cut across it will be found to have a core of pith,
consisting of thin-walled cells, surrounded by a layer of wood of greater
or less thickness, and that again by a bark of no great thickness, and
covered on the outside with a skin or epidermis. Such sterns of the first
year are usually green, because they contain chlorophyll, and are capable
of manufacturing plant food. The skin of green stems also has air pores,
or stomata, such as leaves have, and takes in oxygen from the atmosphere
for the purpose of breathing. The above, in general terms, is the structure
of a stem of one season's growth.

In order fully to understand the thickening of a stem it will be neces-
sary to consider the structure of a shrub or tree, say the stem of an Apple
tree of some size. If the stem is cut across, the pith (fig. 20) will be found
in the centre, and probably of small size, owing to the pressure of wood
upon it. This is surrounded by a number of layers of wood, each ring
corresponding to one year's growth, and thus the age of the tree may be
determined. This wood is made up of cells, wood fibres, and vessels more
or less thickened internally. Surrounding the wood in winter is a thin
layer of thin-walled cells, termed the cambium (No. 8), to be considered
presently. Outside of the cambium is a ring or rind forming the bark,
now of considerable thickness by comparison with that of a Stock or
Gourd. It has lost its skin or epidermis (No. 1), and in place of the
stomata, openings loosely filled with cork cells, and known as lenticels,
may often be observed on stems or branches not too old. These are
breathing pores. A large portion of the bark is made up of corky tissue
(No. 2), gradually breaking away from year to year, while the inner

The Science of Plant Growing

portion is younger and more fibrous. Collectively the various members of
the rind are known as bark. Some of the fibres are thickened, and known
as hard bast (No. 5), while the inner cells remain thin-walled, constituting
the soft bast (No. 6). Archangel mats are made from the hard bast of the
younger portion of the bark of the Lime tree. Sieve tubes (No. 7) are
included in the hard bast, which serves to give toughness and pliability
to stems and branches. The bark, collectively, also serves to protect the
cambium from injury and the wood from decay; hence one good reason
for careful pruning and judicious lopping of all trees whatever.

3*5678 9 10 11 12

Fig. 20. Portion cut from a Branch of a Leafy Tree x about 200 (diagrammatic)

1, Superficial coat (Epidermis). 2, Cork (Periderm). 3, Cortical parenchyma. 4, Vascular bundle
sheath. 5, Hard bast. 6, Soft bast. 7, Sieve tubes. 8, Cambium. 9, Pitted vessel. 10, Wood
parenchyma. 11, Scalariform vessels. 12, Medullary sheath. 13, Medulla or pith.

The Cambium. Even in winter, when the trees are leafless and com-
paratively at rest, the thin-walled cells of the cambium are small and filled
with protoplasm; it really constitutes the only live portion of the tree at
this period. It forms a thin, cylindrical jacket to the trunk of the tree, and
gradually tapering cylinders to each branch and twig, till continuous with
the small core in each live bud on the tree. The cambium descends to the
roots in like manner. When the temperature rises in spring the cells are
excited into rapid growth, and, with abundant supplies of stored food
close to hand, they soon reach full size, divide, grow, and multiply rapidly.
The cells on the inner side develop new fibre-vascular bundles, side by side,
in a continuous ring all round last year's wood. Those on the outside of
the cambium form new hard and soft bast. Thus the wood increases in

Commercial Gardening

thickness by the deposit of a new ring on the outside of its mass, while
the bark thickens by the deposit of a new ring on the inside of last year's
one.

The existence of the cambium explains the art of budding a Rose,
grafting a scion or shoot of one Apple tree on to another, inarching a
young Vine on the rod of an old one, and the grafting of shoots of a
Clematis, Tree Pseony, and Wistaria on to the roots of another for the
purpose of increasing their numbers. The object in each case is to get
the only live portion of the scion of the tree, shrub, or climber into contact
with the cambium of the stem and root, respectively, used as stocks. The
cambium of the one coalesces or joins with that of the other, and forms
a new layer of wood over the old. If the grafted portion of an Apple or
other tree were examined after one hundred years,
the old cut surfaces would still be present, for
mature or ripened wood, being dead, never unites.
The whole of the wood of a tree, after it is fully
ripened, is dead, though it may exist for one
thousand years or more, protected by the bark,
and be of service to the tree.

Fig. 21. Section of Dicotyle-
donous Stem, showing central
pith, three zones of wood, and
bark on the outside (diagram-
matic)

Fig. 22. Section of Stem of Palm and Fern

Dicotyledonous and Monoeotyledonous Stems. The above descrip-
tions relating to the thickening of stems and the cambium layer apply
entirely to Dicotyledons. The structure of a three-year-old stem is repre-
sented by fig. 21. Trees and shrubs are less numerous amongst Mono-
cotyledons, whilst herbaceous types in cultivation are very numerous.
Structurally they are all much alike, whether herbs, shrubs, or trees, of
one or many years' duration. Palms, some species of Pandanus, and a few
Bamboos are the only plants of tree-like habit or dimensions in the class.
The stem of a Palm may be taken to consider details of structure (fig. 22).
There is no pith in the centre, nor bark on the outside. There is a skin
on the epidermis, and that is permanent. The body of the tree is made
up of short-celled ground tissue, and distributed through this are very
numerous strands or bundles of fibro-vascular tissue. They are isolated
in the ground tissue, and when the cells, fibres, and vessels of which they
are composed have reached their full size, and thickened their walls, they
can make no further growth, as there is no cambium. Towards the circum-
ference of the stem the fibro-vascular bundles are the most numerous, and

The Science of Plant Growing

Fig. 23. Lily Scaly Bulb. Onion Tun icated Bulb

as the cells of the ground tissue in that region thicken their walls greatly,
it follows that the outside of the stem of a Palm is very hard. A seedling-
remains without a stem till the leaves have attained a large size and a
certain number, when the stem rises up almost of the same thickness
throughout. As Palms generally do not branch or increase the number
of their leaves, the thickening
of the stem is unnecessary.
Some species of Dracaena
thicken their stems slightly by
some of the cells of the outside
of the ground tissue retaining
the power of dividing and form-
ing new tissue like the rest.
The stem of a Fern consists of

ground tissue, with an inter- l W<V \U

rupted ring of woody tissue in
the form of curved plates and
isolated pieces (fig. 22). In all
these cases strands of fibro- vas-
cular bundles pass from the wood of the stem or branches into the leaves.

The functions of the stems and branches of all the above plants are to
support the leaves, so that they may be properly spread out to the light,
and to convey water and food to the leaves, flowers, and fruits. As the
stems of trees must be strong to bear the weight of branches and leaves,
so they develop a much larger proportion of woody
tissue than herbaceous plants require to do.

Bulbs, Corms, Tubers, and Rhizomes. A bulb is
really a very much enlarged bud, consisting for the
most part of leaves, with a very short and thin flat
stem. Lilies have scaly bulbs (fig. 23), while Hyacinths,
Tulips, Daffodils, and Onions (fig. 23) have tunicated

bulbs, so called because the sheaths

are continuous all round, like a tunic.

If the sheaths or scales are pulled off

one by one there will remain a thin,

solid part, which is the stem. The Tiger

Lily, and several others, bear bulbils, or

small bulbs in the axils of their leaves,

and their structure is similar to the

parent bulb. The bulbils form a ready

means of propagating the plant (fig. 24).

Conns are produced by the Crocus, Gladiolus, Colchicum (fig. 25) and
others. They consist of a short, flattened stem, covered with dry, scale-
like sheaths, or modified leaves, and surmounted by a tuft of perfectly
developed green leaves. They root from the base. They produce a new
conn, or several, on the top of the old one every year, the old one dying.

Pig. 24. Bulb-bearing
Lily Portion of Stem

Fig. 25. Colchicum
Corm

Commercial Gardening

Small ones are produced at the base of the Gladiolus corm and serve for
propagation.

A tuber is a short, not flattened, but fleshy stem, growing a little at
the apex and dying a little at the base every year. Roots are given off
from the sides, as in the Arum Lily and Caladium. The tuber of the
Potato is the thickened and fleshy end of an underground branch, which
develops into a new plant, the stem of which bears the roots, while the
old tuber dies. The Potato stores starch, while the tuber of the Jerusalem
Artichoke stores inulin, and both are cultivated for these reasons, being
useful for food. The tuber of the Jerusalem Artichoke is of similar origin
or structure to that of the Potato.

Rhizomes are creeping, underground stems, giving off roots below and
leaves and flower stems at the end of the main axis or side branches.

Fig. 26. Rhizome of Iris

Fig. 27. Rhizome of Sedge (Carex)

Examples of stout rhizomes are those of Solomon's Seal and many of the
Irises (fig. 26). Slender rhizomes are produced by Couch Grass, Sedges
(fig. 27), Lily of the Valley, and many others. The stem nature of these
rhizomes may often be testified by the presence of very much reduced
scale-like leaves, as in the cultivated Spearmint and Peppermint.

The object of bulbs, corms, and tubers is to store food with which
to commence growth, flower, and fruit in the following year. Rhizomes
serve a similar purpose as well as to increase the plant and extend it
into fresh ground. Mints are noteworthy in this respect. All of these
types are of easy propagation by offsets and divisions in gardens. By
virtue of the stored food in their bulbs Hyacinths, Tulips, Daffodils,
Snowdrops, and others may be grown in the dark till their flowers are
visible, when they must be placed in the light for the benefit of the
young leaves. The Hyacinths and Daffodils may be, and are, grown
entirely in clean water till they have finished flowering, solely as a result
of the starch stored in the leaves and fleshy stems constituting the bulbs.
They require to be grown in good soil for some years afterwards in order
to recuperate before they can flower as well again.

Besides such modified stem structures as corms, tubers, and rhizomes

A DUTCH TULIP FARM

DOUBLE TULIPS GROWING AT WISBECH, CAMBRIDGESHIRE (Mr. J. W. Cross)

DUTCH AND ENGLISH TULIP FARMS

The Science of Plant Growing 41

there are many plants in which the stems have assumed the form of
leaves. One of thft best-known examples is the Common Butcher's Broom

Fig. 28. Plants with Leaf-like Branches

1, Young shoot of Rugcus Hypoglossum. 2, The same branch fully grown with flowers on the cladodes.
3, Young shoot of Jiuscun aculeatua. 4, The same branch with flowers on the cladodes.

(Ruscus aculeatus); others are Ruscus Hypoglossum (fig. 28) and the
Alexandrian Laurel (Dancea Laurus or Ruscus racemosus). These plants,
being apparently unable to develop true leaves, have modified some of their

Commercial Gardening

shoots for the purpose of assimilation. These shoots are flat and leaf-
like, but it will be noticed that they bear flowers near the centre, a thing
no true leaf does. It will also be noticed that instead of spreading out
horizontally these peculiar shoots (known botanically as cladodes or phyllo-
clades) are set more or less vertically. Other plants with modified struc-
tures are to be found in such genera as Asparagus, Acacia, Eucalyptus,
Grevillea, Phyllanthus, Phyllocactus, Phyllocladus, Semele, &c. [J. F.]

6. LEAVES AND THEIR WORK

Seed Leaves and True Leaves. The first leaves of a plant are those
formed in the seed, and which may or may not rise above-ground during
germination. Those of the Cabbage, Mustard (fig. 13), Gourd (fig. 18),

Beech, and Onion rise above-ground
and become green. As soon as this
has taken place the seedling has
started life on its own account,
manufacturing its own food in the
green seed leaves and stem. The
seed leaves of many plants become
fleshy, store food while in the grow-
ing seed, and never rise above-ground
during or after germination, but
supply food to the seedling till able
to forage for itself. Examples of

Fig. 29.-Vertical section through Leaf of Frawiscea fafe may be geen J n the gar( ] en
eximia, showing Epidermal, Palisade, and Spong n en TI t*^ x ft

Tissue, and two stomata cut through Pea, Sweet Pea, Broad Bean, Scarlet

Runner, Horse-chestnut, and Oak
The seed leaves differ more or less widely in form
All of the plants mentioned in this
paragraph, except one, have two seed leaves or cotyledons and belong
to the class Dicotyledons. The Onion, Lily, and others have only one
cotyledon, and are Monocotyledons. The seed leaves of Iris and grasses
never rise above-ground, and as they have only one each they belong to
the latter class.

The true or rough leaves are those that follow the seed leaves in
succession, increasing in size and varying in form with each individual
till the plant reaches the adult state. The leaves, taken altogether, con-
stitute the foliage of the plant.

Structure and Contents of a Leaf. The naked-eye characters of a
leaf may be seen in that of a Vine. The leaf is three- to five-lobed,
with as many primary veins running from the base to the tip of each
lobe. Smaller veins pass through the leaf in a variety of directions, the
smaller ones forming a kind of netting. The veins are fibro- vascular
tissue that come from the stem, pass through the leaf stalk, and divide

(fig. 19, p. 35).

from the true leaves that follow.

The Science of Plant Growing

into three or five main branches at the base of the blade. The spaces
between the veins are occupied by thin - walled cells of various forms
according to their function. A section
through a part of this kind of tissue
in Franciscea (or Brunfelsia) is shown
in fig. 29. The layer of empty cells on
the upper side is the skin or epidermis,
the cells of which are filled with water
in the live state. The outer walls on
the exposed surface are more or less
thickened, the thickening being termed
the cuticle. In leathery leaves, like
those of a Camellia, Palm, Laurel-
cherry, or Rhododendron, the cuticle
is considerably thickened to keep out water and to prevent the loss of it
from within. In many leaves the interior (fig. 31) of the wall is greatly

Fig. 30. Vertical section through a Leaf, show-
ing Epidermis, Palisade, Spongy Tissue, and a
Stoma cut through

Fig. 31. 1, Shows Epiderm with thickened upper wall and palisade cells beneath, filled with
chlorophyll. 2, Epidermal Cells thickened on one side, with Cellular Tissue beneath.

thickened to impart strength and protection to the softer tissues. Below

the skin are palisade cells, placed at

right angles to the surface and one,

two, or more layers deep. These are

filled with protoplasm, chlorophyll,

starch, sugar, and sometimes other

substances. Between the palisade

cells and lower epidermis lies a mass

of spongy tissue not always so open

as in this particular leaf, but filled

more or less with similar materials

to the palisade cells. The lower

skin shows two air pores or stomata

cut through and leading into breath- Fig. 3-2. stomata

ing or respiratory cavities. The latter

are continuous with others leading

all through the leaf. The air pores

of land plants are most often situated on the lower surface of the leaf, but

may be equally numerous on both sides of the leaves of Iris, Carnation,

Surface view of a portion of the Frond of a Fern,
Nephrodium FUix-mas.

44 Commercial Gardening

and others equally exposed to light on both surfaces. The internal struc-
ture in these cases is alike on both sides. The leaves of Water Lilies and
others which float on water have the air pores on the upper surface; while
leaves developed under water have neither cuticle nor air pores. The
tissue of a Mushroom contains neither chlorophyll nor starch.

Work of a Leaf. The leaves and other green parts of a plant con-
stitute a workshop of many compartments, in which the raw food ma-
terials are organized into more or less simple or complex substances for
the building up of the various parts of the plant body. The green chloro-
phyll granules are the agents, under the influence of sunlight, whereby
these remarkable chemical changes are brought about. Starch is the first
visible product, and first makes its appearance in the form of small grains
in the chlorophyll granules. The leaf breathes by absorbing oxygen from
the air, and that gives it power or energy by which the other chemical
changes are brought about. The oxygen attacks and destroys some of the
material in the cells, unites with carbon to form carbon dioxide, which
is given off into the air as in the breathing or respiration of animals. The
leaf also absorbs carbon dioxide from the air, breaks it up, gives off the
oxygen, and the carbon unites with the elements of water brought into
the plant by the root. The more complex composition of the protoplasm
is effected in the leaf by the addition of the other necessary elements of
plant food absorbed by the roots (see p. 33). This process of building
up organized matter from the raw materials is termed assimilation, and
can only be carried on during daylight, though it may possibly be done
artificially by electric light. Plants which have no leaves, like the Cacti,
assimilate by means of the chlorophyll in their stems and branches.

The effect of light and shade on the leaves of plants is not fully
appreciated by all gardeners. Too often we see plants crowded so much
together that only a very small percentage of the leaves have any
chance of being bathed in sunshine during the day. Fruit growers will
have too many trees to the acre, probably thinking that the crops will
be weighty in accordance with numbers. The exact reverse is really the
case, for the simple reason stated above that only under the influence
of daylight can the starch and other building-up materials be formed in
the cells of the leaves. The great bulk of the dry weight of any plant
is obtained from the atmosphere, not from the soil; hence the necessity
of allowing a fair amount of space between one plant or one tree and
another. (See pp. 108, 141.)

Another kind of work carried on by leaves is transpiration, or the
passing off of watery vapour into the air. The cells bordering the inter-
cellular spaces when gorged with water give off some of it in the form
of watery vapour into the cavities communicating with the stomata.
During daylight, and when the air is comparatively dry, the stomata
open and the watery vapour passes out. The cells bordering the air
cavities would soon get dry and flabby, but prevent this by absorbing
water from cells behind them, and these in turn from cells more deeply

The Science of Plant Growing

seated. This is continued through the leaf, its stalk, the branches, stem,
and roots until a current of water, known as the "transpiration current",
is set up from the roots to the leaves. In the open air and on a windy
day this current is often so great that the roots cannot supply it, more
especially if the soil is dry, and the leaves flag as a consequence. This
phenomenon may often be observed in the case of pot plants if allowed
to get dry, whether under glass or outside. It can be remedied by water-
ing the soil in the pots and by syringing the foliage. The undue loss
of water from plants under glass can be more effectually prevented by
closing the ventilators before syringing, and shading may be resorted to
in extreme cases. The atmosphere then becomes saturated, thereby largely
checking transpiration for the time being, and the
leaves resume their wonted stiffness. This rapid ascent
of water serves to keep the plants cool in hot weather,
the cells turgid, and also brings in plant food. Trans-
piration is a vital process regulated by the protoplasm
in the leaves and is somewhat different from evapora-
tion pure and simple. For instance, a Stonecrop may
be placed between sheets of paper, covered by a board
and held down by a weight. It will continue to elon-
gate and even open its flowers under such conditions;
but if placed in a basin and some boiling water poured
over it to kill it the stems and leaves will part with
their moisture in a few days. At night the stomata
close, and transpiration ceases. Another phenomenon
may often be observed in the morning. Drops of
water may be seen on the tips of the leaves of Aspi-
distras, Arum Lilies, Fuchsias, Chinese Primulas, and
many others as a result of root pressure. Over the
ends of the vascular bundles of the leaves of those
plants water pores are situated, and unlike stomata they never close. The
roots continue to absorb water, night and day, and when transpiration
ceases the cell walls become saturated. Water then filters into the cavities
of the wood fibres and vessels under pressure from the roots until it
reaches the water pores, where it escapes from the overgorged tissues.

Forms of Leaves and their Clothing 1 . Seed leaves are always simple
or in one piece, though they are lobed in a few cases. Simple leaves
(fig. 33) are represented by those of the Cherry, Apple, Fuchsia, and
Camellia. They may be more or less deeply and palmately lobed, as in
the Vine, Ivy, Sycamore, Plane, and Hop. The lobing may be in the
form of a feather, as in the common Polypody, Marguerite, Oak, and
Water-cress. This form is termed pinnatifid. The cutting is carried
still deeper in Celery, Parsnip, and Carrot, and the simple leaf termed
pinnatisect, or it may be twice pinnatisect in the Carrot. Leaves are
"compound" when each separate piece into which they are divided is
jointed, as in the Laburnum (fig. 34), the Virginia Creeper, Horse-chest-

Fig. 33. -Simple Leaf

p, Petiole, with Stipules
at the base ; 1, midrib ; 2, 3,
branches of the midrib.

4 6

Commercial Gardening

nut (fig. 35), and Aralia Veitchi. The latter three have palmate leaves.
The feathered type of compound leaves is termed unequally pinnate in

the Rose, Robinia (tig. 36), Ash, Elder, and
Walnut. The Laburnum and Clover have
ternate leaves, because cut up into three
jointed leaflets. The forms of leaves are prac-
tically endless, and should be studied from the
textbooks.

The surface of leaves may be smooth or
glabrous, that is, without hairs, or they may
be covered with hairs varying greatly in den-
sity, length, or form. Hairs that lie smooth
and close are silky; those that are interwoven
with one another are felted or tomentose (fig.
37); long and loose ones may make the leaves
shaggy or woolly. Amongst the hairs on the
leaves of the Nettle some have a swollen base
and are stinging. Those of the Stock are
branched in a starry fashion and are termed
stellate. To this class belong the hairs on
Draba (fig. 37), while this is carried further
in Elseagnus and other shrubs, the branches
of the hairs being united in the form of cir-
cular scales, like a Japanese parasol in mini-
ature, with a very short stalk. The hairs are
useful in a variety of ways, by running the
moisture off the plants, by preserving the
liquids in the leaves of plants that live in dry places; while the hairs and
bristles on many Cacti serve to keep them cool

under the influence of

a scorching sun in

desert regions.

Arrangement of

Leaves. They are op-
posite or in pairs in the

Carnation and Sweet

William; in whorls of

three in the Oleander,

and in whorls of four,

six, eight, or a higher

number in species of

Bedstraw. They are

alternate in the Lime,

Beech, Elm, and others,

where the third leaf comes in a line with the first, counting upwards or
downwards. They are spirally arranged on the shoots. This also applies

Fig. 34. Seedling with opposite Coty-
ledons and alternate Foliage Leaves
(Cytisus Laburnum)

Fig. 35. Horse-chestnut -Com-
pound Palmate Leaf

. 36. Robinia Compound
Unequally Pinnate Leaf

The Science of Plant Growing

to the Apple, where the sixth leaf comes above the first, after the spiral
has passed twice round the shoots. This means that the leaves are
separated from one another at an angle of two-fifths the circumference

Fig. 37. 1, Felted Hairs on Leaf of Edelweiss. 2, Stellate Hairs on the Epiderm of Draba.

of the stem. These arrangements are intended to distribute the leaves
so that all will get a due share of light. This is well shown in the
Elm (fig. 38) and the Ivy (fig. 39).

Fig. 38. Leafy Horizontal Twig of an Elm showing Leaves naturally arranged to catch the light

Not only are the leaves arranged so as to secure the maximum amount
of light, but they are also so placed as to contribute to the nourishment
of the roots. In the case of such trees as Apple, Pear, Plum, Cherry, Oak,

Commercial Gardening

Chestnut, Beech, Elm, Lime, Ash, &c., the leaves are arranged over each
other like tiles or slates on a roof to throw the water from the centre to
the outside. In this way the rain trickles from one leaf to another, and
the great bulk of it falls around the circumference. It is just at this
place that nearly all the fibrous feeding roots of such trees exist. Con-
sequently, when the rain falls they get the first supplies, and are thus
refreshed and enabled to take up more food from the earth in solution.

In the case of the Yew and many Coniferous trees and shrubs the
rain is thrown inwards as well as outwards, owing to the way in which
the leaves and branches are arranged.

In the case of other plants, e.g. the Caladium (fig. 40), it will be noticed
that the leaves are so arranged that water is thrown to the circumference

Fig. S9. ivy on the ground showing normal arrangement of Leaves to catch the light

or periphery of the plant, to which the fibrous roots extend from the
tubers. On the other hand, in the case of the Rhubarb (fig. 40) the large
leaves directed upwards naturally collect the rain and direct it towards
the centre of the plant, and thus down to the thickened rootstock, the
fibres from which do not extend horizontally. The leaves of Turnips,
Radishes, Beetroot, Parsnips, Carrots, Dandelions, Chicory, &c., and most
bulbous plants are arranged in a similar way, to conduct water inwards
for the benefit of their rootstocks.

Modified Leaves. The scales on the bulb of a Lily are modified by
being fleshy, without chlorophyll, and filled with starch. Those of the
Daffodil and Onion are made up of the sheathing bases of leaves, and go
right round the bulb. The Onion stores a glucose-like substance or grape
sugar in the sheaths of the bulb. The stored materials enable the plants
to make a good start into growth the following year, and to throw up their
flower sterns. In late summer and autumn the apex of each shoot and
twig of most trees is covered with brown scale-like leaves for the purpose
of protection. The flowers of the Peach, Horse-chestnut, and Rhododen-
dron are covered in the same way during the winter. The scales are

The Science of Plant Growing

simply ordinary leaves arrested at an early stage of growth, and have
the same arrangement as they. At the base of the individual flower
stalks in many plants are small leaves, termed bracts; in the Carnation
they come close up to the base of the calyx in two pairs. The bracts are
very numerous in the Marguerite, Cineraria, and other composites, and
closely surround each flower head, like overlapping scales. The bracts
surrounding the clusters of flowers of the Poinsettia are large and highly
coloured.

Fig. 4U. Transmission of Water by Leaves towards circumference in (1) Calladium, and towards

centre in (2) Khubarb

The leaves of some plants, like the Sarracenia (fig. 41), Darlingtonia
(fig. 41), Nepenthes or Pitcher Plant (fig. 41), and Heliamphora nutans
undergo complete changes in appearance for special purposes, chiefly for
the purposes of catching insects and afterwards digesting and absorbing
them. In the case of the Sarracenia, Darlingtonia, and Heliamphora the
leaves roll themselves into a tube or trumpet, on the inner surface of
which a honey-like substance is secreted, and on which numerous sharp,
bayonet-like hairs point downwards. The insects, being attracted by the
honey, enter and feed till satisfied, but when they attempt to get out they
are repulsed by the bayonet-like hairs, and eventually sink back exhausted
and die.

In the case of the Pitcher Plant (Nepenthes) the leaves are normal flat
expansions for a considerable length. The tissue on each side of the midrib

VOL. I. 4

Commercial Gardening

Fig. 41. Pitcher Plants

1, Sarracenia variolarix. 2, Darlingtonia cali/omica. 3, Sarracenia laciniata. 4, Nepenthes
villosa, reduced to one-half natural size.

suddenly ceases to grow, and the midrib develops by itself for several
inches. Eventually, however, a pouch-like organ or "pitcher" is formed

The Science of Plant Growing

at the tip, and is provided with a lid. This soon opens and allows the
ingress of various insects, which ultimately meet the same fate as those
entering the other plants referred to. In fig. 41 (4) the stout downward-
pointing teeth around the rim of the pitcher are shown.

Another plant with similar contrivances of modified leaves is the
Australian Pitcher Plant (Cepha-
lotus follicularis), (fig. 42).

The Fall of the Leaf. From
the earliest development of the leaf
in spring, preparations are being
made at the base of its stalk,
whereby it will be thrown off' in
autumn in the case of deciduous
trees and shrubs. This is brought
about by the development of a
layer of cork cells right across the
stalk, exclusive of the vascular
bundles. During the autumn, but
especially in October and Novem-
ber, this layer of cork becomes
completed by the maturing and
dying of the cells, and it needs
only a breeze of wind or a night's
frost to snap the vascular bundles
and bring the leaves down in
showers. The leaves of the Ash
are still quite green when this
happens. This state of maturity
in the leaves of the Peach is
favoured by giving abundant
ventilation both at the top and
bottom of the house in the case
of planted trees. Those in pots
should be stood outside after the
fruit is gathered. Pot Vines may
be served in the same way. Estab-
lished Vines that are tardy in dropping their leaves may be assisted to
mature them by an abundant ventilation, with a dry atmosphere, and a
gentle heat from the hot-water pipes. It would be unwise to hasten
the process unduly by keeping them very dry at the roots.

[J. F.]

Fig. 42. Cephalottts follicularia

52 Commercial Gardening

7. MOVEMENTS OF WATER AND FOOD
PRODUCTS IN PLANTS

Root Pressure. Having considered the mechanism and some of the
properties and contents of roots, stems, and leaves, the way is now clear
to discuss some of the phenomena exhibited by plants as a whole or in
a connected way. There is no regular circulation of sap in plants com-
parable to the blood in animals, nor a constant flow in any one direction,
except temporarily. The flow is in many and diverse directions, according
to the particular kind of work being conducted and the part of the plant
where it is taking place. The movement is a progressive, not a circulating
one. Root pressure, taken on the whole, is the most constant or continuous
force at work in causing a rise of watery fluid in the plant. The pressure
it exerts may be most readily observed in spring, when all the tissues of
deciduous trees and shrubs are gorged with water, prior to the expansion
of the leaves. The Vine exhibits this pressure in a marked degree, and
though it varies within limits, according to the size and vigour of the
plant, it has been found to support a weight of nearly 15 Ib. to the
square inch. This alone enables the sap to rise to the apex of the
longest rod, because the force of capillary attraction must also be reckoned
with when it is remembered that the cavities of the fibres and vessels of
the wood get filled with water and air a combination that is difficult to
move. Trees, shrubs, herbaceous plants, and annuals exhibit this root
pressure, but in low-growing plants it is most observable at night and
early in the morning, that is, some time after transpiration has ceased and
before it commences to take effect again with daylight and a drying atmos-
phere. Root pressure is of great importance to plants that are making
their growth, by keeping their tissues gorged and extended with water,
without which growth would be impossible. It is equally important to
deciduous trees and shrubs, which require a considerable force to expand
their winter buds and urge them into fresh growth. Plants grow more
rapidly by night than by day, because root pressure is then exerting its
full force. Even if this is not sufficient to raise water to the tops of the
tallest trees, a considerable pressure is exerted on the buds by the expansion
of the air bubbles in the water of the wood cavities as a result of the rise
of temperature in spring.

Water of Transpiration. As above stated, this current is set up by
the action of the leaves, and by some has been described as a " transpiratory
pull". The effect it has towards the base of the stem is that of "suction".
It acts only during the day, and, in the case of deciduous trees, only comes
into play when the leaves are expanded and the air pores or stomata are
sufficiently developed to commence work. When transpiration has been
at work for a time the cavities of the wood fibres and vessels get drained
of their liquid contents and filled with air, root pressure is subjected to
a negative pressure as a result, and the up current of transpiration is

The Science of Plant Growing 53

dominant. When pot plants and those in the ground are well supplied
with water, and their leaves do not flag, it is clear that the great volume
of water being given off by the leaves must be coming directly from the
roots, and that the absorbent activity of the latter is equal to the demand
made upon them. It has been calculated that hundreds of pounds of water
are given off by the leaves of trees on a hot day (see p. 120). The water
of transpiration is the most rapid current of watery fluid known in plants,
and is most characteristic of woody plants; it is more feeble in herbaceous
plants with a less-developed vascular system; and non-existent in cellular
plants. Since the vessels of the wood are filled with air, the water must
necessarily travel in the walls of the wood, so that there is a continuous
passage or highway for it from the longest or remotest root fibres to the
tips of the leaves. In trees, like the Oak, Ash, Lime, Apple, Cherry, and
all other Dicotyledons, there is one main current through the trunk. This
flow is chiefly through the younger or sap wood, also known as alburnum,
less feebly through the heart wood or duramen, owing to obstructions
caused by age. The pith and bark may be removed without causing any
diminution in the rise of the sap. In Monocotyledons, like Palms, there is
not one main current, but hundreds of small ones in the trunk of a good-
sized tree. The transpiration current rises in the small, isolated fibro-
vascular bundles distributed through the ground tissue.

In the case of the two great causes of the movements of water in
plants just discussed, it must be presumed that the temperature is adequate,
since they take place under natural conditions. When Vines, Peaches,
Figs, Melons, Cucumbers, and Tomatoes are being forced, out of their
natural season, the necessary temperature best suited to each subject
must be supplied artificially. Feeding, watering, and the amount of
atmospheric moisture have to be controlled likewise by the cultivator, if
the best produce is to be secured. Light is liable to be deficient in winter,
and full advantage must be taken of it, considering how vital it is to
growing plants, from the start till the fruit is matured. This requires
properly constructed houses with- the glass kept clean. Ventilation, during
the middle of the day, at least, is beneficial in promoting transpiration,
drying the atmosphere, keeping the functions of the leaves in healthy
condition, and hardening the tissues of stems and leaves by the proper
thickening of their cell walls, thereby preventing them from becoming
unduly " drawn ". The houses can be closed early in the afternoon, thereby
conserving the sun heat, if any, for that is more favourable to growth
than artificial heat. The foliage may be syringed, if the nature of the
weather for the time being warrants or requires it; transpiration will
be immediately checked and root pressure will soon begin to exercise its
powerful effect upon growth, so that no time is lost by giving timely
and judicious ventilation.

Transport of Food Materials. All the food of green plants is manu-
factured in the leaves and other green parts, and it follows that it must be
transported or conveyed to the various points where growth is going on.

54 Commercial Gardening

When the temporary reserve in leaves consists of starcn, it is first con-
verted into liquid sugar or glucose, and can then be conveyed to the
growing points of stems and branches, with the young, undeveloped leaves
upon them, to flowers, fruits, and seeds. This necessarily means minor
currents of slow motion, with usually short distances to travel. Towards
the end of the season, when growth is more or less completed, much of
the food prepared in the leaves must be carried away and stored in the
trunks of trees, in bulbs, corms, tubers, tuberous roots, taproots, and other
parts of plants according to the kind. This implies downward currents
of water, containing the food materials dissolved in them, and these must
also be slow movements. In the case of trees and many other plants it is
well known that a considerable number of new roots are made in autumn.
This is due to the warmth of the ground and the autumn rains, as well
as to the existence of a plentiful supply of ready-made food. The rain
softens the previously dry and hard earth, and thus enables the roots
to penetrate it and extend their system. In trees this food must often
travel considerable distances, but rapid transport is favoured by the
presence of sieve tubes or continuous vessels in the hard bast, situated
in the inner and younger layers of bark. In Palms and other Monocoty-
ledons this hard bast is situated in the isolated fibro- vascular bundles, as
there is no bark in these cases. Storage may take place in cells that
contain no protoplasm.

Water Plants. As these contain little (or no) woody matter in their
tissues the rise of sap is of a feeble character, but when wholly submerged
there is no transpiration current at all. When the roots are in soil, food
would be brought in that way, while the oxygen for breathing purposes
and the carbon dioxide absorbed by the leaves are taken directly from
the surrounding water. The leaves and stems have no cuticle, so that
each cell comes in direct contact with water holding food in solution.
Floating plants get all their food directly from the water, except the
carbon dioxide of the air available to the exposed leaves.

Sap in Winter. When the leaves fall in autumn, transpiration ceases.
Root pressure continues till all the tissues get filled with water and turgid,
including the cavities of the wood fibres and vessels, which also contain
air. The gradual falling of the temperature also makes the roots less
active, though not entirely dormant. A considerable number of plants
bloom in winter and require a modicum of water. Evergreen trees, shrubs
and herbs, which retain their leaves, must have a certain supply of liquid
to keep them turgid and alive. The roots themselves keep extending for
an unknown length of time after the fall of the leaf, except when the
ground is frozen; and what is used up in these various ways must be made
good by the absorbent hairs and superficial cells of the younger roots. It
is natural and necessary that the roots of plants belonging to temperate
climates should have an adequate supply of water even in winter. This
explains bud-dropping in Peaches that have been allowed to get over dry
at the roots in winter till the buds perish, as the extremities of the trees

The Science of Plant Growing 55

are the first to suffer. Then when growth recommences in spring the dead
buds are thrown off, if not before. Camellias suffer in the same way, in
conjunction with fluctuations of temperature. If a period of dry weather
succeeds the transplanting of Hollies, Laurel-cherries, Conifers, and other
evergreen subjects in winter they often get killed, thus proving that the
leaves give off more water from their surfaces than the mutilated roots can

supply.

Bleeding*. If a Vine rod is cut into the wood in spring, before the
expansion of the leaves, it will bleed strongly for many days, and may even
die or become so weak as to be useless. Its tissues are gorged with watery
fluid containing a considerable amount of liquid plant food, dissolved by the
water from cells where it was stored. Root pressure is very strong at this
period, and the vessels of the wood of the Vine are very large. Much of
the stored food is thus lost, as well as the pressure of sap necessary to start
the dormant buds into fresh growth. If a Vine is cut in June or July,
when in full leaf, it will not bleed, because the vessels are then filled with
air, as a result of the transpiration current. Inarching of Vines should not
be attempted till they are fairly into leaf, for these reasons. If pruning
is accomplished in autumn, before the wood is perfectly ripened, Vines often
bleed in spring when root pressure becomes strong. This phenomenon of
bleeding, when cut in spring, may be observed in various other plants,
including the Birch and Maple. The former will bleed at a considerable
height from the ground (12 to 15 ft.), though most strongly near the base
of the trunk. Sugar is extracted from the sap of the Sugar Maple, and
Rubber from the sap of various Rubber Trees. [j. F.]

8. MODES OF GROWTH AND VEGETATIVE
REPRODUCTION

Monopodial and Sympodial Stems. When a seedling of a shrub or
tree has completed its first year's growth, it usually terminates in a bud,
covered with scales. If, on the resumption of growth next spring, this bud
continues the growth of the stem or axis, the latter would be monopodial,
and would continue to be so from year to year, so long as this order of
growth is maintained. The Conifers are good examples of monopodial
stems, particularly the species of Pinus, Abies. Picea, Sequoia, and Arau-
caria. If the leaders of such trees get broken, or eaten off by animals, or
killed by frost, they rarely recover themselves by the production of a new,
upright axis. Araucaria excelsa is a rare exception to this rule. If the
leader is cut off for the purpose of propagation, one or more upright shoots
on the old stock will result, and these may be utilized in the same way.
The side branches are useless, because they do not grow into true tree
shape, even though they produce roots. The side branches are secondary
monopodia, continued by growth at the apex, but they always retain the
same relation to the primary axis. Trees of this character may often be

56 Commercial Gardening

improved by stopping the growth of too rampant lateral shoots, but not
the leader.

Sympodial stems are very numerous, and are not the result of the
continuous growth of the primary axis from year to year. For instance,
a seedling Vine would be monopodial until it produces a tendril, which is
the termination of the primary axis. A bunch of flowers or berries is the
equivalent of the tendril, and in any of these cases the axis is continued
by the growth of an axillary bud or axis that pushes the primary one to
a side. It will be noticed that the tendril or bunch of flowers is always
opposite to a leaf, not in its axil. A similar method of growth may be
noted in the Tomato. The first bunch of flowers is really the termination
of the axis of the seedling plant. An axillary bud grows
strongly and pushes the bunch of flowers on one side, and
in its turn terminates in a bunch of flowers, and so on
indefinitely. The number of bunches on a single-stemmed
Tomato is an index to the number of axes thus super-
posed, and forming the "sympodium" or combination of
several separate axes. This mode of growth is brought
about in the Willows by the dying of the terminal bud at
the end of each season, and as a result of it the growth
next year must be continued by an axillary bud. Sym-
podial branching may be observed in the Lilac and Horse-
chestnuts. Whenever a stem or branch ends in a bunch of
flowers, the axis afterwards dies back to the first pair of
buds, which will produce two new axes, if they are leafy
buds, but if flower buds, then growth must be continued
from a lower pair of buds.

Forms of Inflorescence. When flowers occur singly
at the end of an axis, as in the Tulip, it is terminal and

,., , , , a . , , . . Fig. 43. Racemose In-

SOlltary; and when only one flower is produced in the florescence- indefinite

axil of an ordinary leaf it is termed axillary and solitary.
More often two or any larger number of flowers are associated together on
a floral axis, with or without bracts at the base of the individual flower
stalks, and such an association is termed an "inflorescence". The floral
axis shows greater variation in the modes of branching than the ordinary
stem. The monopodial or indefinite form is seen in the Wallflower,
Rocket, Lily of the Valley (fig. 43), and Laburnum, in each of which the
inflorescence is a raceme. The lowest flower is the oldest and first to open,
and is succeeded by others in centripetal order, and each is furnished with
a stalk of its own. The spike is also monopodial, and differs from the
raceme by the absence of stalks to the flowers, as in Orchis and Verbena.
The corymb is a form in which the lower flower stalks are long, so as to
bring the flowers all to the same level, as in Star of Bethlehem. The umbel
has its flower stalks all of the same length, and arising from one point, as
in the garden Polyanthus, Cowslip, and Cherry. The compound umbel is
seen in the Carrot, Parsnip, Parsley, and Celery. The first or primary

A DUTCH HYACINTH NURSERY

A BULB FARM AT WISBECH, CAMBRIDGESHIRE (Mr. J. W. Cross)

DUTCH AND ENGLISH HYACINTH FARMS

The Science of Plant Growing

flower stalks do not bear flowers, but give rise to secondary umbels of
stalked flowers. The capitulum (fig. 44) is seen in the Daisy, Dandelion,
and Marguerite. It consists of an aggregation of small flowers or florets,
in a head, surrounded by numerous bracts. The outer florets are the oldest
and first to open, as in other indefinite inflorescences. The panicle is a
branching inflorescence, the branches of which may be in racemes, as in the
Cabbage, or in spikes, as in Beet.

Sympodial or definite inflorescences are fairly numerous, but all are
characterized by the axis terminating in a flower which is the oldest and
the first to open, but the stalk soon ceases to lengthen, and all the other
flowers are produced on branches which spring from a point lower down

and soon overtop the primary axis. The various
forms of definite inflorescence are termed cymes.
The dichasial cyme is seen in the Stitchworts
(Stellaria), Lych-
nis, and others, in
which both lateral
branches are de-
veloped equally,
each terminating in
a flower (fig. 45).
The scorpioid

cyme is seen in
Forget-me-not and
Heliotrope. The
corymbose cyme is
that in which the
branches all ter-
minate on the same

level, and the Sweet William comes near this type. The panicled cyme
may be seen in the herbaceous Spiraeas.

Flower Buds and Pruning". The art of pruning cannot be properly
accomplished without a close study of the habit and mode of growth of
each species of plant whose cultivation is undertaken. The object of
pruning in each case should be strictly kept in view, and the time and
method of operating guided accordingly. Apples, Pears, Plums, Nuts, and
Cherries form their flower buds in the late summer and autumn previous
to their expansion in spring. In most cases they are produced on short,
lateral spurs, and may readily be distinguished soon after the fall of the
leaf by their plump and rounded form. Those of the Morello Cherry,
Peach, Nectarine, and Black Currant are scattered along the shoots of the
previous year, and these must be retained full length or only the weak tips
removed. Red and White Currants flower chiefly on buds thickly clustered
on the old wood, so that the young shoots should be cut away almost
to the base, except the leaders of young bushes, which may be left 4 to
6 in. long. The Vine flowers on the wood of the current year, so that the

Fig. 44. Inflorescence (Capitulum)
of Dandelion

Fig. 45. Cymose Inflorescence Definite,
the central flower opening first

58 Commercial Gardening

laterals may be pruned back to one or two good buds near the main rod.
Hybrid Perpetual and bush Tea Roses produce their flowers on the growths
of the current year, and for this reason may be pruned hard back to get
good flowers. Climbing Tea Roses, like Gloire de Dijon and Bouquet d'Or,
Climbing Hybrid Teas, Noisettes like William A. Richardson, and Wichu-
raiana Roses, must not have their long young stems cut hard back, or few
or no flowers will be obtainable during the forthcoming season. Banksian
Roses produce their flowers on shoots of the first or second year's growth
from the main stem, and these secondary or tertiary shoots must be tied
or nailed up full length. All these climbing types require thinning chiefly,
and two-year-old stems removed to prevent crowding. Deutzias, Guelder
Roses, Lilacs, Cytisus, Genista, Forsythia, Hydrangea hortensis, and other
shrubs that set their buds on wood of the previous year must not have
these cut back till after the flowering period, and then it should be done
at once where necessary.

Propagation by Roots. Many plants may be propagated by cutting
up the roots into short lengths and inserting them as cuttings, and in the
absence of seeds they may be rapidly increased in this way. The roots
of the Gean (Prunus Aviuni), Plum stocks for varieties of garden Plums,
Poplars, and English Elm naturally develop suckers on their roots and
may be propagated in this way. The roots of Bouvardias, Senecio pulcher,
Anemone japonica, Ailanthus glandulosa, Seakale, Horse Radish, and many
others may be cut into short pieces and inserted as cuttings, when they
give rise to buds which grow into plants. Some of these roots are fleshy,
but in any case they can only give rise to buds owing to the presence
of formative matter or reserve food in them, usually starch. The under-
ground parts of Mints, Solomon's Seal, Lily of the Valley, and many
others used for propagation are not roots but rhizomes or underground
stems, and branches in the case of the Potato and Jerusalem Artichoke.

Propagation by Stems. This is the most common method of in-
creasing plants, whether by cuttings, budding, grafting, inarching, layering,
rhizomes, corms, eyes, or runners. Due care must be taken as to the
likely places where starch or other reserve material may be stored. For
instance, a Dahlia cutting, with a piece of the old tuber, will strike with
more certainty than a piece of the young stem alone. The same applies
to cuttings of Everlasting Peas, Lychnis chalcedonica flore pleno, L. dioica
flore pleno, Gypsophila paniculata flore pleno, Begonia Gloire de Lorraine,
and other choice varieties, which it is desirable to keep true to name.
They should be cut as near the rootstock as possible. The same reason
holds good with cuttings of Roses and many other shrubs, to be cut at
a joint, or with a heel of the old wood. Such cuttings are always more
solid at a joint than elsewhere, and less liable to damp off, but there is
always a greater storage of food in those places than between the joints,
because it comes from the leaf, and the bud or young shoot in its axil
has to be fed.

Propagation by Leaves. Many Ferns, including a large number of

The Science of Plant Growing

Aspleniums (&g. 46), Bryophyllwn calycinum (tig. 46), Tolmicea Menziesii,
Cardamine pratensis, and its double variety naturally produce buds on
the margins, base, or upper surface of their leaves, which grow into
plants under conditions favourable to the production of roots. The
leaves of Begonia Rex and its varieties may be induced to form buds
artificially by cutting through the thick ribs, laying the leaves on sand,
pegging or fastening them in position in a moist, warm frame, till small

tubers bearing a bud are
formed. On the other
hand, those leaves may be
cut into strips, each with
a thick rib, and inserted as
cuttings in sand. Leaves
of Gloxinias, Streptocarpus,
and allied plants may be
dealt with in the same way.
The fleshy leaves of Coty-
ledon (Echeveria), Semper-
vivum tabulceforme, and
the bulb scales of many
Lilies and Hyacinths may
be pulled off in their en-
tirety and laid on sand, kept
moist, or lightly dibbled
into the sand, and they
will form small or young
plants. Lastreas, Scolo-
pendriums, and other ferns
often form a small plant at
the base of the leaf stalk,
or may be induced to do
so by inserting the thick
base in sand and keeping
it moist. Reserve materials
are present in all these

cases, together with a plentiful supply of water within the tissues, and
this serves to keep the leaves alive and carry the food materials to the
point where a tuberous callus is formed, from which the roots are emitted.
The leaves of the Cotyledons have a cuticle as well as a layer of wax,
which prevents the escape of their sap, and they must not be kept wet
by too frequent watering, or they will damp off. It is possible that most
leaves could be rooted in this way if they could be kept alive without
damping till roots are formed.

All the above are methods of vegetative or asexual reproduction, and
their object is to multiply the plant and keep varieties true to character
and name. They furnish a means of increase where no seeds or spores

Fig. 46. Formation of Buds on Fronds and Foliage Leaves

1, 2, on the pinnules of A&plenium bulbiferum; 3, on the margins
of the lobes of the leaves of Bi-yophyllum calycimnn.

Commercial Gardening

are obtainable, or might not come true to the parent, and in the case of
choice and rare ferns may be the only means cf perpetuating them.
None of the above processes gives rise to a new individual, but merely
young or rehabilitated pieces of the old ones, and this is what vegetative
reproduction implies. [j. F.]

9. THE FLOWER AND ITS FUNCTIONS

The Parts of a Flower. Phanerogams, or flowering plants, differ
from Ferns and other vascular plants in the great modifications which
the leaves have undergone in the construction of the flower. A complete
flower consists of four sets of organs, termed respectively the calyx,
corolla, stamens, and pistil. Each member of these sets
or whorls of organs consists of a leaf, modified according
to the function which it has to perform in the economy
of the plant. The axis bearing these floral leaves ceases
to lengthen when the flowering stage of the plant has

been reached.

1. The Calyx. The number of

parts forming the calyx varies, but

four (as in the Wallflower) and five

(as in the Buttercup) are extremely

common numbers. These parts are

situated on the outside of the flower Fi - 48 - - campanula

- , r . /. Flower, showing a regu-

proper, and when tree irorn one an- i ar flower with flve-
other are termed sepals: but when Pf te , d c , alyx and corolla -

The leaf on the pedicel

Fig. 47. Strawberry
Flower

p, petals ; , sepals.

is called a bract.

more or less united they are described
as the segments, lobes, or teeth of the
calyx, according to the length of the free portion. Usually they are small,
green, and serve to protect the other parts of the flower. In the Christmas
Rose (Helleborus niger), Marsh Marigold (Caltha), Delphinium, and Aconi-
tum they are large, highly coloured, showy, and perform the function
of the corolla in attracting insects.

2. The Corolla. The second set of organs, proceeding inwards, con-
stitutes the corolla; and, if the parts are free, they are termed petals,
as in the Buttercup, Rose, Camellia, Sweet Pea, and Strawberry (fig. 47).
Very often all the pieces are united for a greater or less part of their
length, when the corolla is said to be gamopetalous, as in the Primrose,
Salvia, Dandelion, Stephanotis, Gardenia, and Campanula (fig. 48). The
lower part of these flowers is the tube and the expanded portion the limb;
the latter is often two-lipped, as in Salvia and Lamium (fig. 49, l). The
corolla is bell-shaped in Campanula, funnel-shaped in Convolvulus, and
so on. It is usually the most showy part of the flower, protecting the
inner parts, but designed more particularly to attract and guide insects
to the nectar. In the Christmas Rose, Winter Aconite, and Globe Flower

The Science of Plant Growing

(Trollius), the petals are small and modified to form nectaries, and this
would explain why the sepals are large and highly coloured. The modi-
fications are endless, and usually have some reference to the method of
fertilization. The corolla is said to be regular when all the parts are
alike, but irregular when they are of different sizes, shapes, or disposition,
as in Salvia, Snapdragon (fig. 49, J), or Sweet Pea.

Fig. 49. Forms of Corolla

A, Cruciate. B, Caryophyllaceous. c, Papilionaceous. D, Tubular. E, Campanulate. F, Funnel-shaped,
o, Rotate. H, Ligulate. I, Labiate. J, Personate. K, Personate and spurred. L, Nectaries.

In many flowers the outer and inner whorls, representing calyx and
corolla, may be of the same texture and colour, and in such cases they
are collectively termed the perianth, as in Daffodils, Lilies, Amaryllis,
Tulips, Crocuses, Irises, and other Monocotyledons. In many Dicotyledons,
however, there is only one set of organs, which may be green or coloured,
and the term perianth is also applied to them, as in Daphne, Marvel of
Peru, Knotweeds (Polygonum), and Docks. The large white leaf of the
Arum Lily is not a corolla, but a large bract enclosing a spike of small
flowers, and termed a spathe.

3. The Stamens. These are situated just inside the corolla, and may
vary from one to a hundred or more in one flower. They consist of a
filament or stalk, comparable to a leaf stalk, and an anther on the top,
corresponding to the blade of the leaf. The filament may be absent but
the anther is essential, as it contains the powdery-looking pollen grains
(fig. 50) that fertilize the embryo cell. The filaments may be free from

Commercial Gardening

one anotner, or united in one, two, or more bundles, these various con-
ditions being indicated by special names in the textbooks, which may be

consulted where necessary.
They may also be seated
on various parts of the
flower, and the distinc-
tions are very valuable in
systematic botany.

4. The Pistil This in-
cludes all the organs in the
centre of the flower, and
being the female parts of
the same, are as essential
to it as the stamens. Tak-
ing the White Lily as an
example, the lower, inflated
portion is named the
ovary, the long stalk on
the top of it the style, and
the knob on the apex of
that the stigma. If the
ovary be cut across, it will
be seen to have three cells
filled with numerous ovules
or young unfertilized seeds.
The three cells are an in-
dication that the pistil con-
sists of three carpels or
modified leaves closely
united. The pistil of the
Buttercup, Potentilla, and
Strawberry (fig. 51) con-
sists of numerous carpels,

all free from one another, and popularly termed seeds, but each consists

of an ovary, style, and stigma. The
Barberry, Pea, and Peach have a pistil
consisting of one carpel in each flower.
The number of carpels that go to the
composition of the pistil of the Poppy
may be determined by the number of
rays to the stigma and the incomplete
partitions that project into the in-
terior of the ovary. This may be
done in the Mallow, Carnation, and

Carrot by counting the number of styles, and in Geranium, Pelargonium,
Mint, and Salvia by counting the number of stigmas.

Fig. 50. Pollen Grains highly magnified

1, Cobcea scandens. 2, Pinus Pumiiio. 3, Passiflora kermexina.
4, Cirecea alpina. 5, Nymphcea alba. 6, Epilobiuin august if olium.
7, Cucurbita Pepo. 8, Hibiscus ternatus.

Fig. 51. Strawberry with Section, showing
thickened receptacle bearing the true fruits or
pips on the surface

The Science of Plant Growing 63

5. The Ovule. A young seed before it has been fertilized is termed
an ovule. A Buttercup or Strawberry contains only one ovule in each
carpel; a Cherry or Peach contains two, but only one reaches maturity.
The Pea may have from four or five to a dozen, arranged along the edges
of the ventral suture, one of the two separable edges of the pod. The Pansy

Fig. 52. A Monoecious Plant

1, Pistillate flowers on upper part of twig of Oak (Quercus pedunculate); staminate flowers in drooping catkins
below (nat. size). 2, Single pistillate (female) flower. 3, Three staminate (male) flowers, x 4.

has numerous ovules, in three distinct rows on the side walls of the ovary,
and defined as parietal. In the White Lily they are on the inner angles
of the cells of the ovary, and therefore axile. ' The part to which they
are attached is termed the placenta in each case. The placenta is free
and central in the Chinese Primula, and the ovules are inserted all over it.

6. The Receptacle. After all the parts of a flower have been removed
there remains, as a rule, a small core or axis, which is the receptacle, and

6 4

Commercial Gardening

is really a very short piece of stem that bore the various floral leaves
just described. It undergoes many modifications in different plants. In
the Buttercup and Wallflower it remains small; in the Strawberry it
becomes enlarged and pulpy (fig. 51); in the Raspberry and Bramble it
becomes large, conical, and spongy; in the Apple it grows up around the
carpels, completely enclosing them, and, though only a fleshy, cellular
flower stalk, it forms the edible portion of the fruit. The receptacle of

Fig. 53. A Dioecious Plant

1, Twig of Crack Willow (Salix fragilis), with pistillate (female) catkins. 2, Twig of same with
staminate (male) catkins (nat. size).

the Cherry or Peach forms a little cup round the base of the ovary, and
carries the sepals, petals, and stamens on its edges. In the Rose or Brier
it forms a hollow tube enclosing the carpels, and becomes the brightly
coloured hip at maturity. The Fig is also a hollow receptacle, enclosing
a whole inflorescence of numerous small flowers.

A flower is said to be hermaphrodite when it contains both stamens
and pistil; male, when it contains stamens only; female, when only the
pistil is present. A plant or tree is monoecious when male and female
flowers occur on different parts of the same individual, as in Begonia,
Cucumber, Marrow, Oak (fig. 52), and Melon; and dioecious when only

The Science of Plant Growing

male flowers occur on one individual, and only female on another, as in
the Willow (fig. 53), Poplar, Aucuba, and Ash.

Pollination and Fertilization. When pollen is carried from the
stamens of one flower by insects, the wind, or other agency, and deposited on
a stigma of another flower, the process is called pollination. If the pollen
is placed on the stigma of the same flower, that would be self-pollination;
and if the flower accomplishes this itself, as it frequently does, that would
be automatic self-pollination. The
word fertilization is often loosely
used to imply the same act, but no
fertilization can really take place
till the pollen tube has reached the
germinal vesicle in the ovule and
formed a union with it.

Sexual Reproduction. Ex-
cept in minor details this is ac-
complished much in the same way
in all vascular plants, which in-
clude Ferns, Selaginellas, and their
allies. The pollen grains of a
flowering plant are equivalent to
the microspores of a Selaginella;
and the anther in which they are
produced to the microsporangiurn
of Selaginella. The germinal
vesicle or egg cell is equivalent to
the megaspore, and the embryo
sac in which it is produced to the
megasporangium of a Selaginella.
The pollen is the male element and
the egg cell the female. A pollen
grain has two coats or skins, and
when it reaches the stigma the
inner coat soon after protrudes
and grows down the loose, con-
ducting tissue in the interior of the stigma and style, in the form of a
blind or closed tube (fig. 54), then passes into the ovary, and enters the
micropyle or opening of the ovule until it comes in contact with the egg
cell (fig. 56). The growing or elongating pollen tube contains two nuclei,
and the first and larger one fuses with the nucleus of the egg cell and
fertilization is complete. In other words, the male and female elements
have united to form one cell, which forthwith develops into an embryo
or new individual. If the pollen has been brought from another plant
of the same kind, the embryo will inherit the characters of both parents,
and, though it may not seem to differ much from either when it grows

into a plant, it is usually more vigorous than an embryo which is the
VOL. i. 5

Fig. 54. Flower of Cistus: Sepals and Petals removed.
The Stamens are hypogynous, and some of them have
their Anthers in contact with the Stigma. The Pollen
Tubes are shown passing down the Style and entering
the Ovules.

Commercial Gardening

result of self - fertilization.
This is sexual reproduction,
and is vastly different from
the increase of numbers se-
cured by cuttings, layers, and
offsets, which are merely pieces
of the individual from which
they were taken.

Cross-breeding* and Hy-
bridization. When pollen is
taken from the flower of one
variety and placed on the
stigma of another variety of
the same species, and plants
raised from the seeds so ob-
tained, the process is rightly
termed cross-breeding. Of the
hundreds of varieties now in
existence of the Sweet Pea,
Carnation, and Chinese Pri-
mula, none of them are hy-
brids, although cultivators often speak loosely of hybridizing them. A

hybrid can only be produced by
ft taking pollen from the flower of one

species and placing it on the stigma
of another species, such as Cattleya
labiata and C. bicolor, Pelargonium
zonale and P. inquinans, Begonia

Fig. 55. Section of Style of Lilium Jlariagon, shoving Pollen
Grains on the Stigma, and sending down their Tubes along the
conducting tissue of the Style

Fig. 56. Section of an Ovule, showing the entry of the
Pollen Tube into the Embryo Sac

Fig. 57. Lythrum. Section of Flower,
showing two rows of Stamens one short,
one long. The Style is short.

boliviensis and B. Pearcei. Species belonging to different genera are
sometimes hybridized, such as Cattleya labiata and Lcelia crispa, and the

The Science of Plant Growing 67

resulting seedlings named, Laeliocattleya or Catlselia, by compounding the
names. Three genera have been united by crossing the product of the
first two with a third, namely, Brassavola, Cattleya, and Laelia, and indi-
cated by the name Brassocatlselia.

Hybrids are by no means always sterile, as was at one time supposed,
when they were termed "mules". The hybrid progeny of Orchids, Be-
gonias, Roses, and other plants may be used as parents for still further
improving the race. To what extent hybridization can be carried is un-
certain, as it largely depends on sexual affinity. Some varieties refuse
to cross, and many species refuse to hybridize with one another. The
difficulties are increased when it is attempted to mate species belonging
to different genera, and the members of different natural orders refuse to
hybridize at all. When species are distantly related, the possibilities of
hybridizing them can only be determined by experiment. When this is
done artificially it largely depends on the skill of the operator, who must
get the pollen in mature and good condition, and apply it to the stigma
when perfectly developed and receptive, either moist, as in an Orchid or
Rose, or covered with a fine downy pile, as in a Carnation, Begonia, Chrys-
anthemum, or Cineraria. To make sure of the pollen applied being effective,
the anthers of the flower to be operated upon must be removed before they
have burst, and after applying the pollen the flower should be covered with
thin gauze to exclude insects for a few days till the pollen has time to take
effect. In winter and under glass this is scarcely necessary, and in summer
tiffany may be put over the open ventilators to exclude insects.

Plants grown for seed in the open field must be kept widely apart, if
they are at all closely related, or insects may mix the stocks by carrying
the pollen of one to another. Varieties of the cabbage tribe, such as
Cauliflower, Kale, Brussels Sprouts, and Cabbages are very liable to be
indiscriminately crossed in this way and rendered useless. Sports may be
explained by the characters of a cross-bred or hybrid plant becoming
separated or dissociated in certain of the buds on the stem, and the flowers
of such buds, or the shoots from them, are of a different colour.

Various Forms of Fruit. As the result of the fertilization of the
egg cell and the production of an embryo, the pistil becomes the young
fruit. Usually this includes only the ovary and stigma, with the style if
present, as well as the ovules. In those cases where the receptacle grows
up around and adheres to the ovary walls, that also forms part of the fruit,
as in the Cucumber, Melon, Apple, and Daffodil, with the withered remains
of the flower on the top of it. The simplest forms of fruit may be seen
in the Buttercup and Strawberry, in which the small, mature fruits
resemble seeds. In the Christmas Rose and Columbine it becomes dry,
splits along one edge, and is termed a follicle; in the Pea it splits along
both edges and is named a legume or pod. The Pansy, Poppy, and Snap-
dragon have dry seed vessels, opening by valves or pores and named
capsules. The fruit of the Gooseberry and Currant is a true berry, because
inferior, one-celled, and pulpy. The fruit of the Apple is called a pome.

Commercial Gardening

Fig. 58. Section through
the Fruit (Drupe) of a Plum,
showing the Epicarp (ep) or
Skin, the Sarcocarp (sar) or
Flesh, the Endocarp (en) or
Stone. In the centre is the
solitary Seed or Kernel.

The inner wall of the ovary becomes bony in the Cherry, Peach, and
Plum, while the portion between this and the skin becomes pulpy; the
fruit is a drupe (fig. 58). That of the Raspberry and Bramble consists of
an aggregation of drupels or small drupes. The Mulberry fruit resembles
it, but is made up of a large number of flowers, the perianth of which
becomes fleshy, and the fruit is termed a sorosis.
This sisterhood of clustered fruits is carried still
further in the Pineapple, the flowers, pistils, bracts,
and axis forming one pulpy mass. The Fig has a
fruit consisting of a whole inflorescence, enclosed in
the hollow, pulpy axis, each seed, so-called, being a
tiny fruit from the botanist's point of view.

The circumstances which favour the ripening of
fruits under glass are a drier atmosphere, plenty of
air, and a higher temperature than usual to secure the
chemical changes, whereby harsh and acid juices may
become pleasant to the palate, and starch and other
reserve matters may be converted into sugar. Black

grapes require to be shaded by their foliage, and white varieties to be
exposed. Cucumbers require a thin shading to prevent the development
of too much carbon in them, which means the loss of the green colour.
Apples, Pears, Plums, Cherries, Peaches, and Nectarines require full expo-
sure to sunlight to change the chlorophyll granules in the skins into red

and yellow ones. Apples and Pears grown
in pots take on the brightest and darkest
colours if stood out-of-doors to mature.

Seeds. When the ovule is fertilized by
the union of the nucleus of the pollen tube
with the egg cell it becomes a seed. At this
stage it consists of three parts: (1) The testa,
or skin, made of two layers or coats, and
belonging to the mother plant; (2) the endo-
sperm, a mass of tissue developed to nourish
the embryo; and (3) the embryo or young
plant. The endosperm and embryo are new
developments, resulting from the act of fer-
tilization. As the seed progresses to matu-
rity it undergoes great changes, and, in many
cases, remarkable developments (figs 59, 60).
The testa may remain thin and membra-
nous, especially in those cases where it is
covered by the walls of the fruit at maturity and after it has fallen away
from the mother plant, as in the Buttercup, Clematis, and Chrysanthemum,
the fruits of which must not be mistaken for seeds. The testa also remains
thin in the Peach and Cherry, where it is protected by the bony endocarp
or stone. It becomes leathery, spongy, or fleshy in different species of Iris,

Fig. 59. Seeds, showing the Outer Skin
or Testa with rugged prominences or pro-
jections. The sections show the Seeds cut
lengthwise, and show the Embryo with its
two Cotyledons, and the Radicle surrounded
by the Perisperm.

1, Hue (Ruta graveolens).
below.

2, Snapdragon

The Science of Plant Growing

and crustaceous in the Honeysuckle ; while it may be much wrinkled,
crustaceous, tubercled, or warted in species of Delphinium. Tubercled seeds
may be found in Lychnis, Silene, and Stellaria; netted or pitted ones in
Poppy, Passionflower, and their allies. In the Willow Herb (Epilobium)
the seeds develop a long pencil of hairs at the top, and in the Willow and
Poplar the parachute of hairs arises at the base; and in all cases the hairs
are intended to assist the dissemination of the seeds by the wind. This,
also, is the intention where the testa develops round the edges or at both
ends into a membranous expansion or wing, as in the Bignonia and Moon-
seed families, in the Stock, Arabis, and many others.

As the seed matures, the endosperm
grows and becomes fleshy, horny, or
mealy in different families, and fills up
the interior of the seed to a greater or
less extent, or may disappear altogether,
as in the Crucifers and Rose families,
where the embryo uses it all up before
maturity. The embryo may remain
small or grow to fill the seed, and inter-
mediate stages are very numerous. It
may store all the food materials in itself
and the cotyledons may remain thin or
become fleshy. At maturity the seed
assumes various colours, such as red,
brown, white, or black, and these colours
are a sign that growth has ceased. The
testa dries up, but the endosperm and
embryo remain alive and retain theii*
protoplasm and other contents, though
the embryo alone is capable of resuming
growth in most cases. The Castor-oil
seed is an exception, for the endosperm
also grows during germination.

Germination. The essentials to ger-
mination are air, moisture, and a suitable temperature. The oxygen of
the air is necessary for the purpose of respiration, to keep the embryo
alive even while it is resting in the dry seed; but before germination can
take place it must respire more freely to induce the chemical changes
necessary for the resumption of growth. Moisture is required to soften
the testa and other hard parts with which it may be surrounded, as well
as to swell up the tissues of the embryo and endosperm, where such is
present. A certain degree of heat is necessary before any growth can
take place, and this has to be determined in each particular case. The
seed of the Sycamore may germinate at freezing-point, but many other-
plants require a considerably higher temperature. On the other hand,
very few species of plants will germinate in a higher temperature than

Fig. 60. Seeds with the Testa or Skin winged,
or provided with a tuft of Hairs, the object in
each case being to secure the dispersal of the Seed

1, Lepigonum. 2, 3, Aspen. 4, 5, Cinchona.

Commercial Gardening

104 to 108 F. The best temperature, therefore, for germinating seed lies
somewhere between freezing-point and the last-named figures. The tem-
perature at which seeds will germinate most quickly is the best in all
cases; hence the value of ascertaining this approximately. As soon as
germination is completed most plants will thrive best with less heat, more
air and light, but particularly those seedlings whose cotyledons rise above-
ground and become green.

Seeds which contain no endosperm usually germinate very quickly
because the embryo already contains all the reserve food within itself, as
in the Cabbage, Turnip, Mustard, and Willow. The Almond, Plum, and
Cherry take a long time to soften the hard shell in which the seed is
enclosed, while endosperm is absent. The seeds of many trees fail to
germinate at all if kept dry over the winter before being sown. If allowed
to get dry, the seeds of Canna often require filing and steeping in warm
water before they will absorb sufficient water to induce germination.
Carrots, Parsnips, Parsley, and Onions take a long time to germinate,
because the small embryo has to feed on the endosperm and grow to some
size before it can leave the seed. Grass seeds have a starchy endosperm,
but germinate quickly because the embryo is situated on the outside of the
mass and remains attached to it by the cotyledon while the first leaf rises
above-ground. The stored materials are converted from insoluble into
soluble matters, which the embryo can absorb. Starch is changed into
liquid sugar or glucose by a kind of ferment set up in the endosperm or
in the tissues of the embryo itself. Many seeds contain a large quantity of
oil, which gets changed into starch and finally into sugar, before being used
up by the embryo. Light is unnecessary for these processes, and is detri-
mental chiefly by drying up the moisture and causing great fluctuations of
temperature. After the seed leaves are expanded light is of the greatest
importance. Oily seeds soon lose the power of germination; starchy seeds,
like wheat and barley, and the seeds of the Pea family, which contain no
endosperm and little or no oil, may live for ten to forty years, but the
process of breathing alone would, in the course of a relatively short period,
consume the live substance of any seed. [j. F.]

SECTION III
Methods of Propagation

In commercial gardening enormous numbers of plants are disposed of
each year from the open ground and from under glass, and as soon as one
crop is finished, another, as a rule, is ready to take its place. To maintain
the equilibrium it is obvious that in accordance with the disposal of the
plants a corresponding number must be raised each year.

Crops are raised in various ways, viz.: From (1) seeds; (2) cuttings of
stems, leaves, or roots; (3) layers; (4) runners; (5) suckers; (6) offsets;
(7) bulbils; (8) division of the rootstocks; (9) budding; (10) grafting and
inarching. The commercial grower naturally adopts the method of propa-
gation that will produce him a saleable crop within the shortest possible
period, although a particular crop may be raised by more than one
method.

Seeds. Although in a state of nature this is the natural means of re-
producing plants, it is not always the best or most satisfactory under other
conditions. A whole host of plants, however, are raised from seeds each
year, and in this way the seed trade already referred to at p. 2 is kept
well employed. Such plants as annuals and biennials are necessarily raised
from seeds, because they cannot well be perpetuated in any other way,
owing to the short time they live. All natural species that ripen seed in
our climate, and many florists' flowers, may be raised from seed, and the
young plants will reproduce all the features of their parents. In the case
of many florists' flowers, however, like Begonias, Dahlias, Chrysanthe-
mums, Carnations, Snapdragons, Pentstemoiis, Petunias, Gloxinias, and
many others, special varieties are propagated by other means, as they
are unlikely to come perfectly true if raised from seed. Variations may
and do occur as the result of cross-fertilization by insect agency, and this
is often sufficient to alter the character of the flowers. All choice varieties
of fruit trees and roses are not raised from seeds, except in the first in-
stance. Most vegetable crops, being of an annual or biennial nature, are
raised from seeds. Great care, however, is taken by raisers to keep their
stocks of special varieties quite pure and free from cross-fertilization with
inferior strains. The plants to bear seeds are grown in places as far as

72 Commercial Gardening

possible from those of a similar nature, to prevent the pollen being carried
from one to the other.

Seeds vary considerably in size, from almost dust-like grains to that
of Peas, Beans, Acorns, and upwards, to Coconuts. They are borne either
singly or severally in their pods or ovaries, some plants like Begonias,
Poppies, Marrows, &c., having from 300 to 600 seeds or more in a pod,
while there are several thousands in many orchids. Whatever the size
may be, each seed is the result of an ovule having been fertilized by the
contents of the pollen tube that penetrated the tissues of the pistil from
the stigma downwards, as the result of the pollen grains germinating. In
the case of Fern spores which are popularly known as " seeds " the process
is quite different, and is explained in the article on Ferns in Vol. II.

Each seed, when thoroughly ripe, contains sufficient nourishment to
start the young plantlet in life under favourable conditions, and the main
object of the cultivator is to get the seed-leaves up to the light as soon
as possible, so that they may be able to assimilate the carbonic acid gas
from the atmosphere to develop further tissue. Some seeds germinate
more quickly than others, and seeds of the same plant will germinate
either quickly or slowly according as it is in a favourable temperature
or not. Under the best conditions some seeds take a long time to

germinate, often owing to the extreme hardness and thickness of their
coats. Experience has proved, however, that hard -coated seeds will
germinate readily as soon as they drop from the parent plant; but if kept
for a few months, and then sown, a considerable time may elapse before
they begin to sprout. For this reason seeds of Cannas, Nelumbiums, and
many of the Leguminosae are often filed before being sown, to reduce the
thickness of the hard bony coat surrounding the embryo plant within.
It may be worth while to quote the following remarks of the late Herr
Max Leichtlin, from the Gardener's Assistant: "If practicable, it would
be best to sow all seeds of hardy plants at once when ripe; we only delay
sowing for the sake of convenience, because we should, in the case of
autumnal sowings, be obliged to house a very large number of pans and
boxes of young plants too small to pass the winter outside. Hard-shelled
seeds must be sown at once, also all seeds of hardy bulbous plants. If
seeds of Colchicum be exposed to the air for a few days, not more than
5 per cent come up within a year, and the rest may take five years to
germinate, whereas, sown as soon as the seed pod splits, 30 per cent will
germinate in the first year. Delay sowing the seeds of Lilium, Fritillaria,
Tulipa, &c., and you will lose from 20 to 80 per cent. Campanulas
and Ostrowskya readily germinate when sown at once, but if sowing is
deferred till spring the seeds will probably lie dormant for a year, if they
do not perish altogether."

The following data as to the number of days taken by various seeds
to germinate may be of interest. The night temperature was about 60 F.,
and the day temperature ranged from 65 to 70 F. Those marked with
an asterisk (*"> were sown in the open air.

SHOWING ELECTRIC SEED-CLEANING MACHINERY (James Carter & Co.)

SHOWING MACHINERY FOR FILLING SACKS WITH SEED

SEED WAREHOUSES

Methods of Propagation

Name of Plant.

Date of Sowing.

Date of
Germinating.

Number of
Days.

African Marigold ... ...

April 4

April 9

African Marigold* ... ... ... ...

Antirrhinum, Sunlight
The Bride
Aquilegia coerulea ... ... ... ...

March 3

M 7

March 13
13
24

10
6
21

,, glandulosa
, , hybrids

3
3

28
23

25
20

Auricula, Alpine

,, 18

Calampelis scabra

April 8

April 19

Calendula, Meteor ... ... ... ...

Callistephus hortensis *
Candytuft

8
,, 11

22
, 15

14
4

Centranthus macrosiphon*
Chrysanthemum, tricolor ...
Chrysanthemum, tricolor*

8
4
8
8

22
14
22
22

14
10
14
14

Dahlia, double

French Marigold ... ... ... ...

Gaillardia arista ta ...

,, 5

,, grandiflora

,, 5

7
4

Gilia tricolor*

,, 8

,, 22

Godetia ... ... ... ... ...

Godetia* ... ... ... ... ...

,, 8

,, 22

Hibiscus africanug

Hollyhock, double ...

,, single ... ... ... ...

Ma. h 3

March 1 1

Ipomoea purpurea ... ... ... ...

April 4

April 14

Lavatera arborea, var.
Nicotiana affinis ... ... ... ...

,, 10

March 3

March 13

5
10

,, sylvestris ...

,, 3

Papaver nudicaule ... ... ... ...

April 4

April 12

,, ,, double
Pea, Everlasting

,, 19

4
11

Petunia grandiflora ... ... ... ...

March 3

March 12

Pyrethrum aureum ... ...

>, 7

Solanum giganteum ...

,, pryracanthum
,, robustum ...

3
3

25
,, 25

22
22

,, Warscewiczii
Stocks, Ten Week

April 4

25
April 10

Sweet Sultan ...

Whitlavia grandiflora
Zinnia elegans

4
5

9
9

5
4

,, Haageana

,i 10

The table on next page shows the number of days it took various vege-
table crops to germinate from seeds sown in the open air.

Vitality of Seeds. While some seeds retain their vitality or power
of germinating for twenty years or more, it is generally safer to utilize
fresh and well-ripened seed to secure good plants. The stories circulated
as to the seeds of "mummy" wheat germinating after two thousand or
three thousand years have been discredited long ago, and need not be
considered. As a rule, fleshy seeds like Peas, Beans, Acorns, Horse-
chestnuts, Sweet Chestnuts, and Walnuts lose their germinating powers
more readily than smaller and less fleshy seeds; but the latter also
deteriorate if kept more than two or three years. In the case of
Cucumbers and Melons, growers generally consider that they obtain a

Commercial Gardening

Name of Crop.

Date of Sowing.

Date of
Germinating.

Number of
Days.

Beet, "Blood Red

March 21

April 21

Dell's Black

,, 27

Broad Bean, Early Long Pod
Carrot, Early Scarlet Nantes

April 1
4

29
21

28
17

,, Long Surrey Bed ...

March 14

French Bean, Canadian Wonder

July 14

July 25

Lettuce, All the Year Round

March 19

April 4

,, Commodore Nutt

Feb. 2

March 12

,, Paris White

March 19

April 4

Onion, White Spanish

April 1

Parsnip, The Student

March 21

,, 27

Pea, Veitch's Perfection

July 14

July 23

Spinach, Victoria

April 1

April 1 7

Turnip, Early Snowball

March 14

April 1

> >

., 27

greater percentage of plants from two-year-old seed than from one-year-
old, which would rather indicate that they require a further period to
mature properly after being taken from the fruit and cleansed.

Seed Sowing". Seeds are sown in the open air either "broadcast"
or in " drills ", and under glass in pots, pans, or boxes of varying sizes.
In the latter case the gardener mixes his compost beforehand, and drains
his seed pans or pots more or less carefully and elaborately according to
the class of seeds he intends to sow. Special pains are taken with minute
seeds such as those of Begonias, Gloxinias, Rhododendrons, &c., and with
the spores of Ferns. The gritty surface soil is rendered very fine by pass-
ing through sieves of small mesh, and when pressed down firmly makes
a fairly solid rooting medium for the plantlets, and also prevents the seeds
from dropping down too far from the light. In the case of Orchids, which
are now raised from seeds in thousands, the dust-like seeds are sown on
the surface of the mossy or fibrous compost in which the parent plant is
growing, the little plants being transferred to thimble-like pots when large
enough for the purpose.

In the open air, market gardeners and farmers prepare their soil also
in accordance with the nature of the seeds. For small seeds the ground,
after being ploughed or dug, is well harrowed or raked, and rolled if
necessary to secure sufficient firmness. When large quantities of seed are
being sown it is more economical and quicker to use a drilling machine.
The seeds are put in a box, and drop through a slot at regular intervals
in the drills that are made as the machine is drawn or pulled over the
surface. The depth of the drills and the distance apart are regulated
beforehand. Generally speaking, however, seeds are sown far too thickly,
and in the case of such crops as Carrots, Parsnips, Turnips, Beet, Mangels,
Peas, and Beans about 95 per cent of the seedlings have to be destroyed
to make room for the others to grow. The waste is not so great with crops
that are to be transplanted, as every plant almost may be utilized.

When large areas are to be sown broadcast a sowing fiddle (fig. 61)

Methods of Propagation

is sometimes used. This contrivance takes its name from the fiddling
action of the operator when distributing the seeds. It consists of a light
canvas-covered box frame, which is suspended by a strap from the right
shoulder, and is carried under the left arm. At the base of the box is
a neck with a controlling slide through which the seed passes, its flow
being made continuous by a jigger action from an eccentric from a spindle
which carries at its bottom a distributing disk. This disk, which has four
radiating ribs, is actuated by means of a thong which forms the string
of the bow, and which is passed once round the spindle. When recipro-
cated, as in fiddling, the bow causes the disk to revolve rapidly in alternate
directions, thus giving the seeds
a throw of 15 to 30 ft. Where
Radishes are grown extensively
under glass the sowing fiddle is
often used for sowing the seeds.
Generally speaking, however, it :'v-:
is more of a farmer's than a s.
gardener's implement. v|

Cutting's. A very large &*
number of plants may be raised '. : ;::
by means of cuttings of the stems '!; : ; : .';
or shoots. Soft-wooded or her- ;/.';
baceous cuttings having leaves "X
are used in many cases, the shoots '///.
being in a half-ripened condition, - : - :
that is, neither too young and
sappy on the one hand nor too
old, dry, and woody on the other. Fig. ei. sowing Fiddle

Such cuttings, according to the

hardy or tender nature of the plant, are usually inserted in sandy or gritty
soil, and most of the leaves are stripped off to check evaporation of moisture
from the tissues through the stomata or breathing pores. One, two, three
or more leaves are retained, according to the nature of the plant, so that
a certain amount of assimilation may be carried on and induce a " callus "
to develop over the base of the cutting. Once the callus is formed from
the coagulated sap, roots are soon emitted, and the cutting then becomes
an established and independent plant. As a rule, stem cuttings are cut
immediately beneath a joint, because at that point the fibrovascular
bundles containing starchy food matters are closer together, and the
callus forms more quickly from the descending sap.

While the cuttings of some plants (e.g. shrubby Calceolarias, Pent-
stemons, Snapdragons, Phloxes, &c.) root freely in cold frames, others
require warmer and more genial surroundings, and must be placed in
a hotbed or propagating frame with bottom heat. Indeed, even with
hardy plants, the application of bottom heat will often induce cuttings
to "strike" or root more readily than they would in cooler surroundings.

Commercial Gardening

Fig. 62. Begonia Gloire de Lorraine : Stem Cutting

In some cases (e.g. Heaths, Epacris)
great care is exercised to encourage
roots to develop. The pots or pans in
which the cuttings are to be inserted
are carefully drained with clean crocks
to within an inch or so of the rim, and
a compost consisting of 1 part peat and
3 parts silver sand is used for the cut-
tings. Glasses are placed over them for
some weeks, to keep a moist atmosphere
around them, and each day superfluous
moisture is wiped from the glasses to
prevent injurious dripping on the cut-
tings. The cuttings of such plants as
Zonal Pelargoniums, Fuchsias, Calceo-
larias, Dahlias, Begonias (fig. 62),
Phloxes, Pentstemons, Snapdragons,
Carnations, Pinks, Lobelias, Aucubas,
Roses, Heliotropes, Euonymus, Golden
Privet, Skimmias, and many others root
readily in any ordinary garden compost of a somewhat gritty nature if

kept shaded from brilliant sunshine, and
occasionally sprinkled overhead when
there is a tendency for the air to become
too dry.

Woody Cutting's. Many hardy trees
and shrubs may be raised from leafless
cuttings of the well-ripened young shoots.
The best time to take these cuttings is
about the end of October and during
November, although many will also root
freely if taken in spring just when the
sap is beginning to rise. With hard-
wooded cuttings the basal half, being the
ripest or most mature, makes the best cut-
ting, and if taken with a "heel" of the
older wood attached it is almost certain
to root. The cuttings vary from 1 in. or
more to 1 ft. in length, and the larger ones
may be inserted about three -fourths of
their length in the soil when placed out-
of-doors. In this way such plants as
Gooseberries, Currants, Roses and Rose
stocks like the Brier and the Manetti,
Dogwoods, Brooms, Cotoneasters, Diervillas (Weigela), Forsythia, Jasmines,
Kerria Mock Orange (Philadelphus), Flowering Currant (Ribes san-

Fig. 63. Shoot of Skimmia japonica Rooting

Methods of Propagation

Fig. 64. Leaf Cutting of Begonia Gloire de Lorraine
A shows old leaf from base of which new plant is arising.

guineum), Willows, Shrubby Spiraeas, Tamarisk, Skimmias (fig. 63), and
many others, are readily raised.

While small herbaceous and leafy cuttings are inserted with a dibber,
which is used for mak-
ing a hole and packing
the soil round the base,
long woody cuttings are
inserted in trenches
made with the spade, or
they may be inserted
with a dibber. In the
first case a line is
stretched the length of
the row, and a trench
with a vertical side is
made with the soade.
The cuttings are then
placed against the ver-
tical side of the trench and pushed into the soil, the distance between the
cuttings being about 3 or 4 in. The soil is placed against them and trodden
down firmly with the feet, being afterwards levelled. When several rows
of hard-wooded cuttings are
to be inserted, about 1 ft. is
left between the rows, to allow
room for weeding and hoeing
during the season of growth.

Vines may be raised from
cuttings inserted in the open
air in the way indicated. As
a rule, however, they are
raised from single eyes in-
serted in small pots in heat.
Clematises may also be raised
from cuttings in the same
way. With some evergreens,
like Aucubas, quite large pieces
of a plant having several leafy
branches will root readily if
placed in coconut fibre or leaf
mould with a little bottom
heat.

Leaf Cutting's. Many
plants may be raised simply from leaves. The well-known Begonia Gloire
de Lorraine and its relatives are largely raised in this way as well as
from stem cuttings. Single leaves with stalk are inserted in sandy soil,
several in a pot or pan. When placed in heat they soon root and develop

Fig. 65. Leaf Cutting of Achi-
menes showing development of
Catkin-like Ithizomes and young
Leaf

Commercial Gardening

young plants from the top of the leaf stalk, as shown in the sketch
(fig. 64). Achimenes are also raised extensively in this way (fig. 65), as
are also Gloxinias, foliage and other Begonias, Echeverias, Kleinias, Cras-
sulas, Pachyphytons, &c. In the case of Gloxinias and foliage Begonias
the leaves are laid flat on the soil, and have slits made across the midrib
and main veins with a sharp knife. They are kept in position by small
stones or pieces of broken pot, and kept moist and warm, and soon develop
little plants from the slits. In the case of the Indiarubber plant (Ficus
elastica), while the single leaves will develop roots, as
shown in the sketch (fig. 66), and remain fresh for
many months, they seem to be incapable of develop-
ing plants.

Fig. 66. Leaf of India-
rubber Plant (Ficiis
elastica) Rooting

Fig. 67. Offsets from a Stonecrop (Seduin dasyphyUum)

1, Entire plant, nat. size. 2, 3, 4, Offsets at different levels on the
stem in the axils of the leaves. 5, Offsets from floral region.

The thick scaly leaves from the bulbs of many Liliums, if inserted in
sandy soil, will produce little bulbs at the base, and these in the course
of two, three, or four years will attain the flowering stage. Echeverias
are readily propagated in the same way, the detached matured leaves giving
rise to plants in due course. Many other fleshy plants may be increased
from their leaves, as shown in the annexed cut of Sedum dasyphyllv/rn
(fig. 67).

Some Orchids (e.g. Thunia Marshalliana) may be raised from stem
cuttings, as shown in the annexed drawing (fig. 68). The stems of Ficus
elastica, cut up into pieces each containing one leaf and an eye, root readily
in a temperature of 75 to 80 F. Dracaena stems cut up in the same
way but without leaves, also root freely, and produce plants when buried

Methods of Propagation

about 1 in. deep in a hotbed of coconut fibre. The tops of Crotons,
Dracaenas, Araucarias, Aralia Sieboldi, and others also root when inserted
in a similar hotbed.

Ringing". This method of propagation may be called overhead layer-
ing. It consists in making an upward or circular slit in the stem of
a plant that has become too tall or leggy. Some sphagnum moss and

leaf mould is then tied round
the wound, and is kept damp
with the syringe every day.
In a short time the elaborated
descending sap from the leaves
develops a callus and a mass of
roots through the moss. When
a sufficient number of roots has
been produced, the rooted head
is severed and potted up. In
this way tall Dracaenas, Crotons,
Cordylines, Aralias, Ficus elas

Fig. 68. Stem Cutting of Thunia Marshalliana

A, Old stem showing fibres from joints. B, Young shoot
with roots at base (i nat. size).

Fig. 69. Aerial Layering

tica, American Carnations, &c., may be propagated, as well as by other
methods mentioned. If considered worth while, trees with branches too
far from the ground might be propagated in this way, but the trouble
would be to maintain moisture round the ringed portion. The sketch
(fig. 69) shows how this method of propagation may be adopted for
trees and shrubs, using a pot with a slit in one side for the purpose.

Root Cutting's. By cutting up the roots of certain plants into pieces
2 or 3 in. long, and covering them with about 1 in. of gritty soil, it is
possible to raise new plants. This method of propagation may be prac-
tised about October and November, of in. February and March, the root

Commercial Gardening

cuttings being inserted in a hotbed of moderate temperature. Some plants
like Horse-radish and Sea-kale are easily and generally raised in this way;
while such weeds as the Bearbind, Dock, Thistle, Dandelion are also in-
creased quite as readily by chopping up the roots. Other plants that may
be raised by means of root cuttings are Anemone japonica, Acanthus
mollis, Boeconia, Dictamnus Fraxinella, the Sea Hollies (Eryngium), the
Globe Thistle (Echinops), the Oriental Poppy (Papaver orientale), Statice
latifolia, &c. Many kinds of trees and shrubs like Hawthorns, Plums,
Apples, Pears, Quinces, Roses, Poplar, Mulberries, False Acacias (Robinia),
Sumach (Rhus), Paulownia, Sophora, &c., may be propagated from root
cuttings.

Layering 1 . This method of propagation consists in making an incision
in a branch or shoot, and then bending it down and covering with soil.

Border Carnations are usually
propagated by layering. In the
open air the work is done about
the end of July and during
August. Non-flowering shoots
are slit upwards with a sharp
knife in a fairly well -ripened
portion, thus forming a "tongue".
The layered shoots are pegged
into the soil with hairpins or

pieces of bent wire, and are
covered with a nice gritty soil,
and given a good watering. At
the end of three or four weeks
a mass of fibrous roots are

emitted from the callused surface of the tongue. Each rooted layer may
then be severed from the parent plant which has been feeding it, and
may be planted out at once, or potted up to be kept in cold frames during
the winter.

In the case of American or Perpetual-flowering Carnations the shoots
may be layered whenever they are sufficiently ripe; but it is found more
convenient, as a rule, to raise them by cuttings, or by " ringing ".

Many trees and shrubs are propagated by layers when they cannot
be raised in any other way, or when they are raised most quickly by
that method. The young shoots near the ground are bent down and
covered with soil, being kept in position by means of bent wires or
wooden crooks. Some plants root readily from the joints without any
incisions being made, but others are slit in the same way as Carnations,
care being taken to keep the tongue open or away from the shoot. In
fig. 70 a shoot a is shown pegged down at 6, while a stake c is placed
to the aerial portion to keep it erect. In fig. 71 the tongue of the
shoot is shown at 6, while another method is shown on the right at /,
where a ring of bark is taken off the wood. It will be noticed that all

Fig. 70. Layering a Woody Shoot

Methods of Propagation

Fig. 71. Layering by Tongueing and Ringing

buds are rubbed off on the portion of stem beneath the soil, while they
are retained on the overground portions shown at 1, 2, and h. Many
fruit - tree stocks, like the Crab and Paradise for Apples, Mussel and
Brussel Plums, Pears and Quinces, the Mahaleb Cherry, ai-e usually raised
from layers, as are also many ornamental shrubs like Magnolias, Cratsegus,
Osmanthus, Phillyrea, Viburnum, Hamamelis, &c.

In the case of such plants as
Vines, Clematis, Wistaria, Lapa-
gerias, and others with long flex-
uous shoots, the latter are bent
down at intervals of a foot or
two, as shown in the sketch
(fig. 72), the portions e being
pegged down and covered with
soil 6, the overground portions
d being furnished with buds.
Owing to the snake -like ar-
rangement of the shoots this
system of layering is known as
" serpentine ".

Many plants like Goose-
berries, Black Currants, Loganberries, and Blackberries, &c., layer them-
selves naturally when the stems are allowed to lie upon the ground, and
they may be propagated in this way if necessary. Many other woody
plants could also be propagated by layering if necessary or desirable.

Runners. A runner is a slender whip-like shoot sent out from the
parent plant to root at some distance away, and at certain intervals to
produce fresh plants. The Strawberry is the best-known example of a
runner-bearing plant, and gar-
deners readily seize upon this
character to raise thousands
every year. New varieties of
Strawberries, of course, are
only obtained from seeds after
a more or less lengthy process
of cross-fertilizing and selec-
tion ; but, once established, new
varieties are also propagated

from runners. Other plants besides the Strawberry throw out " runners "
or "stolons", examples of which are met with in the Sweet Violet, the
Houseleek, some Saxifrages (like 8. sarmentosa), and these may be used
for propagating purposes. In the case of Couch Grass the underground
stolons are produced with more than desirable frequency and pertinacity
from the cultivator's point of view.

Suckers. A sucker is an aerial shoot springing from an underground

stem or root. Suckers usually have some fibrous roots attached to them,
VOL. I. 6

Fig. 72. Serpentine Layering

82 Commercial Gardening

and when severed from the parent may be regarded almost as estab-
lished plants. Such plants as Chrysanthemums, Plurns, Black Currants,
Raspberries, Blackberries, Loganberries, produce suckers freely, and may
be propagated by them. In the case of Apples, Plums, Peaches, Necta-
rines, Roses, &c., any suckers arising are, of course, from the wild stocks,
and are detached as early as possible, unless they are required later on
to form stocks themselves.

Offsets. Most true bulbous plants, like Tulips, Daffodils and Narcissi,
Hyacinths, Liliums, Snowdrops, &c., produce offsets from the parent bulbs.
When the offsets are detached and replanted they produce flowering
plants the following season, or a season or two afterwards. If some
bulbous plants e.g. Daffodils and Snowdrops are left undisturbed for
years they increase rapidly and produce numerous bulbs. Nerines, Vallotas,
Hippeastrums, Crinums, Pancratiums, &c., also develop numerous offsets
from the base of the older bulbs.

Corms as produced by Gladioli, Montbretias, Crocuses, Colchicums, are
known as "solid" bulbs as they have no coats as in Tulips and Daffodils
or thick scaly leaves as in Liliums. They produce numerous offsets, but
the old corm always shrivels up or vanishes while the new ones are
forming on top. In such corms as those of the florists' Gladioli (Brenchley-
ensis. Childsi, Lemoinei, and Nanceianus) numerous seed-like outgrowths
are also to be seen. These are known as " spawn " and will produce new
plants in a year or two if sown like seeds in nice gritty soil.

In the case of tuberous plants like the Arum Lily, Jerusalem Arti-
choke, the Potato, the Dahlia, &c., large numbers of tubers or tuberous
roots are produced, each one of which will give rise to one or more plants.
The tubers of the Artichoke and Potato, for example, if cut into pieces
each containing an " eye " or bud, will produce several plants. The tuberous
roots of the Dahlia and the herbaceous Pseony, however, must have a piece
of the old stem attached, as no shoots are produced by the roots themselves.
The tubers of Begonias, Cyclamen, and Gloxinias may be cut into pieces
each with an eye or sprout.

Underground sterns or rhizomes, as met with in the German, Florentine,
and other Irises, Solomon's Seal, Mint, &c., are utilized for increasing the
stock, each portion having a bud being capable of forming a new plant.

Bulbils. Many bulbous plants like Lilium bulbiferum and others
produce seedlike bodies known as "bulbils" in the axils of the aerial
leaves. These bulbils are capable of producing plants if sown in suitable
soil and grown on for a year or two. (See fig. 24, p. 39.)

In some Ferns, e.g. Asplenium bulbiferum, A. biforme, Woodwardia
radicans, little plants also called " bulbils " appear on the fronds, and
from these large numbers of plants may be raised quickly without having
recourse to sowing spores. These bulbils may be regarded in the light of
aerial offsets. (See fig. 46, p. 59.)

Division of the RootstOCk. A very large number of herbaceous
perennials, both hardy and tender, are more readily increased by splitting

Methods of Propagation

up or dividing the tufts into several portions, each containing a supply
of roots. This operation is done either in the spring or in the autumn.
If plants flower naturally during the spring and summer months they
are usually best divided in the autumn; but if they flower in late
summer and autumn they are generally best divided in the spring. Cir-
cumstances, however, may necessitate plants being divided at any season
if it is desired to raise stock quickly without risking the life of the
plants. Many plants that
do not produce seeds or
spores can only be propa-
gated by division. Many
Orchids, Ferns (e.g. Adi-

\ o

antum Farleyense, and
Nephrolepis), and Bamboos
are raised in this way, as
it is the only one possible.
Budding-. The art of
budding consists in remov-
ing a bud from one plant
and inserting it partly be-
neath the bark in another
growing plant in such a
way that it will obtain
nourishment from its host,
and eventually bear flowers
or fruits. In the open air
budding is generally prac-
tised from the end of July

and during August, but
may be done as late as
September under abnormal
circumstances, such as a

particularly hot and dry F 'g- 73. Shoot of Apple arising from Bud inserted in Stock close
T.I to Ground Line, the Stock being cut back to form a stake to which

season, when the sap may y0 ung shoots are tied
not flow freely until the

weather becomes cooler, or until rain falls. Under glass, budding may be
practised almost at any season when the buds and stocks are in a suffi-
ciently advanced condition, but from January to March is the usual time.
Only dicotyledonous plants can be budded or grafted, because they possess
a cambium (see p. 36), and it is essential also that the bud or graft and
the stock should be in the same family and closely related. Otherwise
the difference in constitution and nature might be so great that union
would be impossible. Thus Roses are budded on Brier or Manetti Rose
stocks; Apples on Crab-apple, Paradise, Doucin, or free stocks; Pears OD
Pear or Quince stocks; Plums, Peaches, Nectarines, Apricots, Cherries
on Plum stocks, and so on with other groups of plants (fig. 73).

8 4

Commercial Gardening

The bud or graft is really a kind of parasite. The plant that springs
from it has no roots of its own. It is dependent upon the roots of the
stock for the crude sap, which is pumped up into its stems and leaves from
the soil. This crude sap, however, is elaborated in the leaves of the scion,
and not in those of the stock; hence the changes are such that the leaves,
flowers, and fruits exhibit the features and usually possess the nature of the
scion and not of the stock, Laburnum adami being a notable exception.

There are several ways in which buds may be inserted, but the best
and commonest method is that known as shield budding or T budding
(fig. 74). The dormant buds are taken from a ripened shoot of the current
year's growth, each bud having a small piece of leaf stalk attached to serve
as a handle. The stocks in which the buds are to be inserted in July and
A August should have been planted the previous

October or November to get them well estab-
lished by then. Buds are either inserted as low
down the stem and as near the root as possible,
or they may be inserted on the topmost shoots
of a stock 3 to 10 ft. high. In either case a
transverse slit is made with a sharp budding
knife, and an upper cut about 1 in. long is made
to meet it, the two cuts forming the letter T.
The flat bone handle of the knife is gently pushed
in the upper slit to open the bark, and render it
easy to insert the bud, which has been severed
in advance and placed between the lips while
the slits were being made. In taking a bud the
chief point is to select one that is dormant, and

neither too young near the top of the shoot, nor too old or sprouting from
near the base. If a flat piece of wood is taken off with the shield of bark
it should be removed, care, however, being taken not to tear out the body
of the bud with it. Some Continental and American budders do not trouble
to detach the piece of wood, but in British gardens it is customary to do
so. The bud being inserted, the bark is then tied round it with raffia or
worsted thread, carefully but firmly, to exclude the air. In two or three
weeks the bud will have united with the stock, and it will be necessary
to cut the tying material. An expert budder will bud from 500 to 700
stocks per day, or more, with the assistance of an intelligent lad to clean
the stocks and tie the buds after insertion.

Grafting". Unlike budding, where a single bud is used, grafting con-
sists in affixing a shoot of one plant with two or more buds on to the stem
of another in such a way that the cambium layer of one must come face
to face with that of the other. The shoot is called the "scion", and the
plant on which it is placed is called the " stock " the latter being already
well rooted and established for twelve or eighteen months in advance to
ensure complete success. As in budding, so with grafting the stock and
scion must be closely related, and belong at least to the same natural

Fig. 74. Showing Stock A, with
T-cut at a for reception of Bud B,
side view of which is given at e, and
inner face view at d

Methods of Propagation

family. There are several
ways in which grafting may
be done, and the principal
ones will be mentioned.

Whip Grafting-. This
is the best method when the
stock and scion (or graft)
are nearly of the same
thickness, and thousands of
fruit trees are propagated
in this way every March
and April in the open air.
Preparatory to grafting
taking place the stock is
usually "headed" back in
January or February; that
is, the stem is cut off, leav-
ing a stump a few inches
high sticking out of the
ground. The cut surface

Fig. 75. A Graft or Scion A, cut and tongued at T to fit top of
Stock B; at o is shown the Graft and Stock united, tied, and
waxed or clayed

The

soon heals, as little or no sap is rising at that cold period of the year,
grafts or scions, which always consist
of ripened one-year-old shoots, are also
severed about the end of January or
February, and are "heeled in" in bundles
under a north wall. This prevents them
starting into growth prematurely, and
keeps the sap in them in a less active
condition than if the shoots were
allowed to remain on the parent plant.
The grafting period in the open air
being reached, that is, in March and
April, a slanting cut is made in the
stock as shown in fig. 75, and a nick
is made in it to form a tongue. The
graft or scion, having two or three
buds attached, is also cut obliquely, as
shown in the figure, and a tongue is
also made in it so that it shall fit into
the one made in the stock. The two
cut surfaces should be about the same
length and width if possible, but it is
not essential. One edge of the scion,
however, must be made to fit flush with
the edge of the stock, to bring the
cambium layer of each face to face, because it is by means of the new cells

Fig. 76. Showing how Badly Treated Young Fruit
Trees are grafted in some Market Gardens

Commercial Gardening

Fig. 77. Cleft Grafting

from the cambium that union is to take place. The graft being properly
fitted to the stock it is then tied round securely with raffia, or matting,
or worsted thread, after which the joint is covered over completely with
grafting wax, or clay made into "pug" by mixing it with a little chopped
hay or straw. A good grafting wax may be made by
boiling in a saucepan some beeswax, resin, and Russian
tallow in equal proportions. While still warm (not hot)
this mixture, which should be of the consistence of
treacle, is easily applied with a little brush or flat piece
of wood. A rough-and-ready method of grafting as
practised in some market gardens is shown in fig. 76,
taken from an actual specimen.

Cleft and Rind Grafting". In the case of old t.ees,
having the stems many times thicker than the scions,
whip grafting could not be conveniently done. The
stocks are headed back at the proper season, and at the
proper time a slit is made in the bark with a strong-
bladed knife, or a cleft is made with a chisel, as shown
in fig. 77 at a. The latter is not a good way to graft,
as it leaves a fissure open in the stem, in which water
collects and rots the wood later on. The slit with the knife is best, and
the bark may be gently opened outwards with the point of a small chisel
or flat piece of steel to allow the graft, which has been cut obliquely to
form a wedge, to be pushed in easily. Two or three similar grafts may
be inserted in one stem if necessary, and if the bark only is open, without

splitting the wood,
the process is known
as " rind " or " crown "
grafting, as shown in
fig. 78.

Saddle Grafting-.
When the stock
and scion are about
equal in diameter
this method may be
adopted, but it is
not so good as whip
grafting and is also
more troublesome to
perform. As shown
in fig. 79, the stock
A is cut up on both

The graft or scion B, having several
buds, is split up the centre, and each half is thinned to make it fit astride
the tapering stock, and so that the inner bark of stock and scion are flush
with each other at least on one side.

Cleft

Grafting

Triangular
Notch Grafting

Fig. 78. Forms of Grafting

Fig. 79. Saddle
Grafting

sides to form a wedge ending at c.

Methods of Propagation

Fig. 80. Side Grafting

Side Grafting*. This is a form of whip grafting, but the stem is not
cut away completely above the point of union. A notch or slit is made in
the side of the stock, as shown in fig. 80 at a, b, and the scions are inserted
and tied. It will be noticed that horizontal or vertical shoots may be
grafted in this way, and after the new shoot has grown to a good length
the stocks may be cut off just above the
point of union.

Herbaceous Grafting 1 . This is ap-
plicable to plants having non- woody stems,
and is practised only for the sake of curi-
osity. Potatoes have been grafted on
Tomatoes, and vice versa ; Cauliflowers on
Cabbages; Zonal Pelargoniums, Dahlias, &c.
It seems, however, to be of real value in
the Australian Glory Pea (Clianthus Dam-
pieri), which grows freely when grafted on
the stems of seedling Colutea arborescens,
but will often perish on its own roots.

Coniferous trees have been grafted with young shoots in the forest
of Fontainebleau and other places, the 'modus operandi, as described by
Du Breuil, being as follows : " When the terminal shoot of the stock a
(fig. 81) has attained about two-thirds of its length, it is cut back with
a horizontal cut to the point where it begins to lose its herbaceous con-
sistence and commences to become woody. The young
leaves are cut off between a and d, a distance of
between 2 and 3 in., leaving, however, about two
pairs at the top d d, to attract the sap. Thus pre-
pared, the stock is split down the middle to the depth
of 1 in. or 1^ in. The scion 6 is cut wedge-shaped,
and introduced into the split, so that the commence-
ment of the cuts on each side of the scion may be
nearly 1 in. below the top of the stock. The scion
should be cut at the place where its consistence is
similar to the part of the stock where it is to be in-
serted. Its diameter ought to be as nearly as possible
equal to that of the stock. The graft being placed,
it is secured with coarse worsted, commencing the
tying at the top and winding it down to the lower
part. In the case of delicate species it is well to
wrap paper round the grafted part as a protection

against the drying action of the sun and air. The shoots at c are then
broken at about | in. from their bases. Five or six weeks after grafting,
the cuts will be completely healed; the tie may then be removed, and the
two portions d furnished with leaves at the top of the stock should be cut
off", otherwise they might give rise to buds, which, in pushing, would weaken
the graft."

Fig. 81. Herbaceous Graft-
ingConiferous Trees

Commercial Gardening

Root Grafting". Many plants are propagated by inserting a short
shoot in a root of a relative or by side grafting. Most of the Tree Pseonies
are raised by inserting a shoot in a cleft of a tuberous root of Pceonia
officinalis, making the edges fit flush on one side, and then tying them
up with raffia, &c. Shoots of Wistaria are also inserted in the fleshy roots
of the same plant, as shown in fig. 82, while garden
varieties of Clematis are grafted in thousands on the
roots of the common C. Vitalba.

Inarching* or Grafting 1 by Approach. This method
of propagation was, no doubt, suggested originally by the
fact that boughs of trees that rub against each other and
wear away the bark become united later on by means
of their cambium layers. Inarching is thus a kind of
grafting, but differs in that each of the plants to be united
is growing on its own roots. It is often practised on Vines.
A shoot of a desirable variety is cut and tongued on one
side to fit into a similar cut and tongue on the undesirable
one that may be worth retaining on account of its state of
development, and to avoid replanting and remaking of the
borders. When the inarched shoot has become firmly
united it is severed from its own feeding base, while the
stock to which it is attached has the portion above the
inarched scion also cut away, thus leaving the lower portion
of the stem and the roots. In this way a new variety
takes the place of the old one without much trouble.

Bottle grafting" is a form of inarching, and has been
practised in connection with Oranges, Vines, Oleanders, and
other woody-stemmed plants. A ripened shoot is taken,
say of a Vine, about 1 ft. long. It is cut about 4 or 5 in.
long, and tongued on one side about the middle, to tit
into a corresponding cut and tongue on the stock. It is tied on securely,
but the base of the shoot is stuck into a bottle of water. The latter
should be replenished from time to time, fresh rainwater being preferred,
and a few lumps of charcoal may be put in to keep it fresh for a longer
period. [j. W.]

Fig. 82. Boot
Grafting Wistaria

A, Shoot inserted in
root B and tied.

SECTION IV
The Science of the Soil

i. INTRODUCTORY

When a man intends to grow fruits, flowers, or vegetables for profit his
first consideration is the "soil". This constitutes his chief raw material,
and he knows that if he makes a mistake in its selection it may lead
him to ruin, or become such a drain upon his resources and labour that
his life becomes one of drudgery, anxiety, and worry.

In these days there is a danger of a good cultivator ignoring the
teachings of his own practical experience, and trusting blindly and im-
plicitly to the dicta of the botanist and chemist, and others whose acquain-
tance with the actual cultivation of plants may be of the slightest. A man
may be told that a certain soil contains enough plant food to last a thousand
years, and an elaborate analysis of the phosphates, potash, iron, magnesia,
soda, lime, and other essential plant foods will be produced in support of
the statement. From a purely theoretical point of view such a statement
may be chemically correct, but the said foods may be locked up or com-
bined in such a way in the soil that it would take generations of hard
work and a mint of money to bring them into anything like an available
condition.

While it would not be wise to ignore the chemical analysis of a soil
altogether, the intelligent cultivator will not rely entirely upon it. He
will use his own judgment, the value of which will of course depend
largely upon his practical experience and observation. He will find a
safer guide than mere chemical analysis in examining carefully the vege-
tation of any piece of land he contemplates cultivating. Here his know-
ledge of plants, their relationship to each other, and the natural conditions
chat suit them will be of great value to him.

" Nor every plant on every soil will grow :
The Sallow loves the watery ground, and low ;
The marshes, Alders : Nature seems to ordain
The rocky cliff for the Wild Ash's reign ;
The baleful Yew to northern blasts assigns,
To shores the Myrtles, and to mounts the Vines."

On poor, sandy, or gravelly soils, for instance, he will notice such plants

90 Commercial Gardening

growing as the Lesser Bindweed (Convolvulus arvensis), the Musk Mallow
(Malva moschata), the Hairy Cinquefoil (Potentilla argentea), the Gallic
Catchfly (Silene gallica), the Speedwell (Veronica officinalis), the Hawk-
weed (Hieracium Pilosella), Chamomile (Anthemis nobilis), Shepherd's
Purse (Capsella Bursa-pastoris), Corn Bluebottle (Centaurea Cyanus),
Poppy (Papaver Rhceas), Heather (Calluna vulgaris), Spanish Broom
(Cytisus scoparius), Bracken (Pteris aquilina), Sterile Brome Grass
(Bromus sterilis), &c.

On wet or marshy soils the following weeds may be found: Dog's Bent
Grass (Agrostis canina), Cuckoo Flower (Cardamine pratensis), Marsh
Thistle (Cnicus palustris), Horsetail (Equisetum arvense), the Marsh
Galium (Galium palustre), Corn Spurrey (Spergula arvensis), Comfrey
(Symphytum officinale), Flowering Rush (Butomus umbellatus), Bulrush
(Typha latifolia, T. angustifolia), Forget-me-Not (Myosotis palustris),
Rushes (Juncus spp.), Sedges (Cyperus spp.), Loose-strife (Lythrum Sali-
caria), Willow Herb (Epilobium), Common Carrot (Daucus Carota),
Butterbur (Petasites vulgaris), Water Ragwort (Senecio aquaticus),
Yellow Meadow Rue (Thalictrum flavum), Ivy-leaved Crowfoot (Ranun-
culus hederaceus), Great Spearwort (Ranunculus Lingua), the Lesser
Spearwort (R. Flammula), the Marsh Marigold (Caltha palustris), Water-
cress (Nasturtium officinale), Sundew (Drosera), Mare's Tail (Hippuris
vulgaris), Water Milfoil (Myriophyllum), Pennywort (Hydrocotyle vul-
garis}, Water Parsnip (Sium), Valerian or All Heal (Valeriana), Bur
Marigold (Bidens cernua), &c.

On chalky or limestone soils: the Pasque Flower (Anemone Pulsatilla),
the Stinking Hellebore or Setter Wort (Helleborus fostidus), the Baneberry
or Herb Christopher (Actcea spicata), Whitlow Grass (Draba muralis),
Penny Cress (Thlaspi perfoliatum), Cheddar Pink (Dianthus ccesius),
Goldilocks (Aster Linosyris), the Fetid Hawk's Beard (Crepis fostida),
Wild Sainfoin (Onobrychis sativa), Chicory (Cichorium Intybus), Fumi-
tory (Fumaria officinalis), Bladder Campion (Silene inflata), &c.

On clayey soil or very heavy loam will be found Docks (Rumex),
Coltsfoot (Tussilago Farfara), Creeping Bent Grass (Agrostis repens),
Floating Foxtail Grass (Alopecurus geniculatus), Sow Thistle (Sonchus
arvensis), Rest Harrow Ononis spinosa.

Where, however, one notices the Hawthorn hedges, Wild Plums and
Sloes, the Elms, Oaks, Beeches, Ashes, and Lime trees growing luxuriantly,
the soil bearing them, or adjacent, may be looked upon as the best for
general gardening or farming. It contains a fair mixture of sand, clay,
lime, and decayed organic matter (humus), and such a soil is likely to
yield the best results if it is properly cultivated, but not otherwise.
The following weeds also indicate a good loamy soil suitable for the
cultivation of Fruits, Flowers, and Vegetables, viz.: Thistles, Stinging
Nettles, Groundsel (Senecio vulgaris), Goosefoot or Fat Hen (Chenopodium
album), Annual Sow Thistle (Sonchus oleraceus), Dandelion (Taraxacum
officinale), Chick weed (Stellaria media), &c.

The Science of the Soil 91

2. CLASSIFICATION OF SOILS

Soils are classified in various ways, according to their texture and
mechanical composition. Thus such terms as poor, hungry, cold, hot, wet,
heavy, light, sour, sweet, are used to denote various conditions; while the
terms sandy, clayey, loamy, chalky, marly, and peaty indicate the pre-
dominating constituent of a particular soil.

Several of these terms really mean the same thing to the cultivator.
A poor, hungry, light, or hot soil, as a rule, indicates one of a sandy or
gravelly nature. Such a soil is " poor " because it is impoverished of plant
foods; it is "hungry" because it eats up enormous quantities of organic
manures; it is "light", not because of its actual weight, but because it
crumbles and falls to pieces easily, and its particles will not cohere and
retain sufficient moisture or food; it is "hot" because its gritty particles
absorb so much heat during the day that moisture is driven away from the
roots of the crops. A " hot " soil also has great variations and fluctuations
of temperature, being generally too hot by day in the summer and too cold
by night in winter. A hot soil, however, that is well manured and supplied
with sufficient moisture is valuable for the production of early crops.

On the other hand, a cold, wet, heavy soil usually denotes one of an
ill-tilled, clayey nature. Such a clayey soil is " cold " because of its
"wetness", the heat of the sun being used to dry up the superfluous
water instead of being available to warm the soil particles and promote
root action. It thus follows that a wet and cold soil is also a "heavy"
one, that is, one very difficult to lift, owing to the cohesiveness of its
particles, and not so much on account of its actual weight.

When a cold, wet, and heavy, clayey soil is also full of decaying organic
material, and is never deeply cultivated, it then becomes "sour". This
sourness is due to the fermentation and decomposition of the organic
refuse, which liberates the carbonic acid gas so freely that oxygen is
driven out of the soil. A good loamy soil even may be brought into a
sour condition by overdressing with stable manure, and by not digging
deeply to allow the fresher air to enter and the water to pass away freely
to the lower strata.

To test a soil for sourness or aciditjr, place a small portion into a clean
Florence flask, adding enough distilled or filtered rain water to cover it.
Boil over a lamp for about fifteen minutes, afterwards allowing the solid
matters to settle. Then pour off the clear liquid, and test with a slip of
blue litmus paper. If the paper turns red, it is a sign that the soil is sour.
To remove the acidity, the soil should be deeply dug, and lime or basic
slag added.

It may be well to say something as to the peculiarities of sand, clay,
loam, chalk, lime, peat, and humus.

Sand. Sand consists of small pieces of hard rock that have been
broken down into various degrees of fineness or coarseness from such

Commercial Gardening

rocks as silica or flint, sandstone, quartz, granite, &c., by the action of the
weather and water. The peculiarities of sand are: it is hard and gritty;
it will not float in water; its particles will not cohere readily even when
wet, nor can they be moulded into any shape for any length of time; it
will not hold water; it absorbs and radiates heat readily; and in a fine
condition its particles are blown about easily by the wind when dry.

When mixed with clay, peat, loam, and other soils sand is useful because
it renders the soil more porous, warmer, easier to work, and better aerated
all valuable properties for plant growth.

Clay. This is also composed of fine particles, but much finer than in
sand, and possessing different properties. The particles are soft and greasy
to the touch when wet, and can be moulded into any form; they also float
in water for a long time and make it " muddy "; they retain moisture for
a long time, and will not allow it to escape readily. When dry, clay cracks
and shrinks; when wet it expands, and becomes very slippery to the foot.

Clayey soil by itself is fit only for making bricks, pottery, &c., the
finest chinaware being made of a whitish clay containing silica, alumina,
and water. When burned, clay undergoes marvellous changes. It is no
longer sticky, plastic, or impervious to water, and its particles are loose,
porous, and brittle. Even when wetted, burned clay can never revert
to its original plastic and slippery condition. In some places the clay soil
is often burned with the object of making it lighter, warmer, and more
porous.

The advantage of clay in a garden soil is that it detains moisture and
manures, and prevents the temperature from rising too high in summer and
from sinking too low in winter, owing to its poor conductive powers.

Loam. Sand and clay in about equal proportions, and with a quantity
of organic material, constitute a " loamy soil " the ideal soil for the hor-
ticulturist or agriculturist. When a loamy soil contains more sand than
clay it is called a " sandy loam "; when more clay than sand, a " clayey
loam". The various compositions may be expressed as follows:

Per Cent
of Sand.

Per Cent
of Clay.

Sandy soil contains ...

80 to 100

20 to

Sandy loam

60 80

40 20

Loam

40 60

60 40

Clayey loam

20 40

80 60

Clayey soil

100 80

Chalk. A chalky soil is one derived from limestone rocks which, when
burned, yield the lime of commerce. Lime differs from chalk in not con-
taining carbonic acid gas; this was driven off in the burning. When lime
is burned it is known as quicklime; and when water is poured on this
it is readily absorbed, expansion takes place, and great heat is generated.

The Science of the Soil 93

The result is then known as hydrate of lime. When quicklime is exposed
for a time to the air, it gradually absorbs carbonic acid gas, and thus
reverts to a chalky or carbonate of lime condition.

Chalk or limestone (calcium carbonate) is known to geologists as organic
rock, because it is made up of the remains of shells and bones of sea and
freshwater fish. This may be seen by rubbing down some fragments in
water and examining the dried sediment under the microscope. Minute
shells, pieces of coral and sponges, and broken fragments of shells will be
observed, as well as the remains of other marine creatures. Limestone hills
and rocks are to be found in many parts of the world thousands of feet
above sea level, and bear silent testimony to the upheavals that must have
taken place on the surface of the globe in past ages. In the same way our
coal seams represent ancient forests and fertile vegetation that have become
submerged, and afterwards covered with deposits of other layers of soil.

Lime. Lime, to use the popular term, is a most important ingredient
in soils, and may be employed in various forms, such as marl, gypsum,
quicklime, chalk, slaked lime, gas lime (or " blue billy "). For a heavy, wet,
clayey soil a heavy dressing of quicklime is one of the ways of bringing it
into a good state of cultivation. In milder forms of chalk (carbonate of
lime) or gypsum (plaster of Paris) it is a valuable adjunct to good garden
soils, especially if they have been overdressed with organic manures.

The advantages of adding lime to the soil may be summed up as
follows:

1. It makes a stiff or clayey soil drier and more porous by making
the sticky particles coagulate or flocculate, and thus leave passages for the
air. This may be proved by putting a little lime into a glass of muddy
water. The particles that would otherwise float about for a long time soon
come together in flocks and drop to the bottom, leaving the water clear.

2. Lime, being an alkali, is fatal to sourness and acidity in the soil,
and renders it "sweet" and favourable to vegetation. Where magnesia
is in excess the addition of lime will rectify any ill effects.

3. Without the presence of lime in the soil beneficial micro-organisms
would not be generated from the organic constituents, and there would
be a lack of nitrogenous food. On the other hand, when a soil has
become too rich in nitrogenous foods, that cause luxuriant, sappy, and
unproductive growths, the addition of lime will soon restore the balance,
although at first giving apparently greater vigour to the shoots.

The presence of lime in any soil may be detected in a simple way.
Take a fair sample and place in a glass, and pour over it some fairly
strong acid, such as hydrochloric. If lime is present a vigorous fizzing or
effervescence will take place; if not, it may be assumed that little or no
lime is present and it should be added.

Peat. This name has been applied to the remains of plants that have
accumulated in the course of centuries on the margins of shallow lakes
and in marshy land. The lakes or marshes gradually disappear with
the encroachment of the vegetation, and the latter becomes pressed down

94 Commercial Gardening

into more or less solid or spongy fibrous layers of organic material often
several feet deep. Wherever natural peat beds exist, they are found on
soil or rock that has been hollowed out like a bowl or saucer into which
the water from the surrounding land drains and keeps in wet condition
for a great portion of the year.

Peat when dry burns readily, and is used in the same way as coal
in parts of Ireland and Great Britain. It absorbs water freely and is
therefore valuable when mixed with sandy soil. Some plants, like
Rhododendrons, Azaleas, Kalmias, Heaths, Andromedas, and many other
Ericaceous plants like to have a good deal of peat in their compost; but
very few plants would thrive in peat alone.

Humus. While sand, clay, lime, and peat are all useful and necessary
ingredients of every good garden soil, each one by itself would be practi-
cally useless. When mixed together in certain proportions they are more
valuable, but they still lack something to make them into a really good
garden soil. It would be possible, for example, to obtain sand, clay, and
limestone from the roadway when excavating for sewers and other pur-
poses. But no one would dream of trying to grow plants upon such
material, even if mixed in suitable proportions. There is evidently some-
thing lacking, and that something is of an organic, not a mineral, nature.

When the decayed remains of plants and the refuse from animals
(including decayed leaves, peat, stable manure, &c.) are mixed with the
mineral ingredients it is found that plants grow well. This plant and
animal refuse in a thoroughly decomposed condition is known under the
name of " humus". One of the most popular forms in which humus is
added to the soil is leaf mould or leaf soil. Every crop would produce
a large quantity of leaf mould every year, but much valuable material
is wasted, and the deficiency must be made up by the purchase of stable
and other manures.

The best kind of leaf mould is seen in natural woods of oak, beech,
lime, &c., more especially in the ditches and hollows where great accumu-
lations have taken place. Leaf mould is largely used in the cultivation
of many kinds of stove, greenhouse, and hardy plants mixed with loam,
sand, and peat in various ways. The beds on which the French maraichers
grow their Lettuces, Endives, Carrots, Radishes, Cauliflowers, &c. (see
Vol. IV), are almost entirely humus, with a certain amount of inorganic
gritty soil; hence the luxuriant and rapid growth that is secured.

Advantages of Humus. The addition of humus to the soil has
physical and chemical effects. Physically humus absorbs and detains
moisture; it raises the temperature of the soil and maintains it in an
equable condition; it keeps the particles of sand and clay asunder and
therefore improves the aeration and porosity; it detains the heat, and
thus prevents the roots of plants being frozen during hard frost. But
humus performs other important functions in the soil, especially in con-
nection with the nutrition of many trees and shrubs and green-leaved
plants generally. It has been discovered that the roots of many plants

The Science of the Soil

(e.g. Oaks, Beeches, Poplars, Elms, Rhododendrons, Cranberries, Bilberries,
Brooms, Heaths, Conifers, &c.) are invested with the filaments of certain
fungi, which, instead of being injurious, are actually beneficial. These
fungal threads are interwoven in the tissues of the feeding roots, and often
look like root hairs, and perform similar functions of absorbing water from
the soil together with the mineral salts and other compounds dissolved
in it. The name of " mycorniza" has been given to these fungi which
envelop the roots of many plants, and it has been proved that they are
not only beneficial and essential to the plants on which they grow, but
that they can only come into existence when humus is present in the soil.
This accounts for the great esteem in which all gardeners hold leaf mould

Fig. 83. 1, Roots of White Poplar with inycelial mantle. 2, Tip of Root of Beech with closely
adherent mycelial mantle x 100 (after Frank). 3, Section through a piece of wood of the White Poplar
with the mycelium entering into the external cells, x 180.

as an ingredient in the soils they use, and they know by actual experience
that a soil without humus or leaf mould would be practically useless for
their plants (fig. 83).

Chemically, humus gives rise to living micro-organisms in the soil,
when lime is present, during the process of fermentation and decay, if
the temperature is favourable, .and thus yields up a supply of organic
food in the process of decomposition.

The following table shows the composition of three different kinds
of humus:

Constituents.

Leaf Mould.

Forest Mould.

Peat Mould.

Organic matter (humus)
Clay and silica (sand) ...
Nitrogen.

per cent.

17-00
79-80
0-50

per cent.

8-46
63-34
0-45

per cent.

18-80
76-05
1-40

Potash

0-31

0-73

0-31

Phosphoric acid ...
Lime

0-06
0-19

o-io

2-08

0-20
0-53

Magnesia
Soda

1-71

o-io

Monoxide

0-26

4-98

0-20

96 Commercial Gardening

3. MECHANICAL ANALYSIS OF SOILS

Besides an examination of the natural vegetation referred to at p. 90
the experienced plant -grower will also make a physical or mechanical
examination. He will handle the soil, feel its texture, noting its colour
and whether its particles cleave together or fall asunder and crumble
into dust; and if he is wise he will also have a good-sized hole dug out
to a depth of 3 or 4 ft. so that he may see the geological formation.
He will then be able to form a good opinion as to what may be done with
the land. If the vertical section of the hole shows a good depth of yellow
loam resting on sand, gravel, or chalk it is a good sign. Such a soil will
contain plenty of plant food, may be easily, deeply, and economically
worked, will not require large quantities of manures, will not be too dry
or too hot in summer, nor too cold or too wet in winter, and will respond
readily to good cultural practice.

It follows that any other soil which does not approach this ideal is
less valuable and may cost a good deal more to cultivate.

To gain a fairly accurate idea as to the physical condition of a soil
a fair sample of it should be taken from the first, the second, and the
third spit down. A cubic foot of each might be taken and weighed.
This multiplied by 43,560 will be the weight per acre. A certain quantity
of soil, say 10 oz., should be spread out and allowed to dry in the sun
and air. Weigh again, to see how much moisture has escaped, and com-
pute the amount per acre. After air-drying and noting the amount of
water given off, the samples should then be baked over a fire until all
the organic material is driven off by combustion into the atmosphere. In
this way the carbon, oxygen, hydrogen, and nitrogen will be liberated, and
the residue will represent the mineral substances which cannot be further
reduced. Then pass each sample through a sieve with an -in. or -in.
mesh, so as to take out all the larger stones. Weigh these also and
compute for the acre. The finer soil left should be mixed with water
in a glass vessel and well churned up with a stick; hot water will free
the finer particles better from the sand and gravel than cold. All the
fine clayey particles will remain suspended in the water and make it
muddy, while the sand and grit will fall to the bottom. By pouring
off the muddy water time after time, until at last the water is quite
clear, the mud or clay will be separated from the sand. Allow to settle,
pour the water off carefully, and when sand and clay are dry they can
be weighed. The result will show the proportion of each in the sample,
and the weight may be computed for the acre.

The weight of a cubic foot of soil of various kinds in a dry and
wet state, and the amount of water each contains, have been computed
>ias follows by M'Connell in his Notebook of Agricultural Facts and
Figures:

The Science of the Soil

Kind of Soil.

One Cubic Foot Weighs.

Amount of
Water in One
Cubic Foot of
Wet Soil.

In Air-dry
State.

In Wet
State.

Siliceous sand ...

Ib.

111-3

Ib.

136-1

Ib.
27-3

Calcareous sand ...

113-6

141-3

31-8

Sandy clay
Loamy clay
Pure grey clay ...
Humus ...

97-8
88-5
75-2
34-8
67-8

129-7
124-1
115-8
81-7
102-7

38-8
41-4
48-3
50-1

48-4

Garden mould ...

The mechanical constitution of a good garden soil for the production
of most fruits, flowers, and vegetables might be stated thus, and assum-
ing that an acre of soil at 1 ft. deep weighs 3,000,000 Ib.:

Clay, 40 per cent = 1,200,000 Ib. per acre.

Sand, 35 = 1,050,000

Lime, 10 = 300,000

Humus, 15 = 450,000

These figures may be compared with the following analysis of a fertile
soil on the same basis:

Per Cent.

Lb. per Acre of
3,000,000 Ib.

Potash

1-03

30,000

Soda

1-97

60,000

1,800

Lime . ... ... ... ...

4-09

120,000

Magnesia

3,900

Peroxide of iron

9-04

270,000

Protoxide of iron

10,500

Protoxide of manganese
Alumina

29
1-36

8,700
40,800

Phosphoric acid

14,100

Sulphuric acid

27,000

Carbonic acid...

6-08

180,000

Chlorine

1-24

37,500

Soluble silica ...

2-34

70,200

Insoluble silica clay \
Insoluble silica sand /
Organic matter (humus)

57-65

12-00
1-00

1,729,520

360,000
30,000

The grower should avoid a purely sandy or gravelly soil, because it

will empty his purse in purchasing manure and supplying water; and

he should shun a wet, heavy, sticky yellow clay such as is suitable for

the making of bricks and pottery, because it would require large funds

VOL. I. 7

98 Commercial Gardening

and many years of cultivation to induce such a soil to bear even reason-
ably good crops. The very worst soils can be brought into a state of
fertility in time, but it will never pay the commercial horticulturist to
waste his time upon them.

A man need not be a chemist to be able to distinguish the differences
between a sandy, loamy, peaty, chalky, or clayey soil, and although each
one contains essential plant foods in varying proportions it would be a
mistake to assume that they are all equally valuable or available.

These remarks relate chiefly to the soil when it is to be worked in
a natural condition by the grower of fruits, flowers, and vegetables in
the open air. Although the grower under glass is not hampered so much
with the natural soil and the weather, it is nevertheless to his advantage

to select the best possible soil on which to erect his glasshouses, espe-
cially if he intends to embark on the culture of such crops as Grapes,
Tomatoes, Cucumbers, Peaches, Nectarines, or any other crop which is to
root in the natural soil. For Melons, Ferns, Cyclamen, Chrysanthemums,
Carnations, Bulbs, Zonal Pelargoniums, Heaths, Marguerites, Roses, and
many other crops, soils have to be brought in and mixed in various
proportions before use. The labour and expense of these operations are
great, in addition to which large sums have to be spent on the erection
of greenhouses and heating apparatus, the purchase of pots, &c.

4. HOW SOILS HAVE BEEN MADE

It is from the sedimentary, organic, and igneous rocks that the farmer
and gardener obtain the soil in which to grow their crops. When these rocks
have been broken down into small particles and mixed in various propor-
tions with organic material, they are capable of yielding up certain foods
to plants with a proper supply of moisture and at a certain temperature.

The various rocks have been converted into soil by natural and artificial
agencies. Amongst natural agencies the most important are the gases of
the atmosphere, water (including rain, rivers, streams), wind, heat and cold
(frost and snow), and vegetation. Amongst what may be called artificial
agencies are the cultural operations of man ploughing, digging, hoeing,
harrowing, and manuring.

The natural agencies may be embraced in one word, " weathering ", and
the cultivator should impress upon his mind what important and powerful
friends he has in them. The action of the weather rain, frost, snow, sun-
shine, wind never ceases; it is wearing away the face of the hardest rocks
and flints, as well as the surfaces of cultivated soils, both day and night,
and bringing them into a more fertile condition. This important work
costs nothing, but how many realize that it is always going on!

It may be as well to consider the individual action of each of the natural
agents.

Water. Whenever rain falls it brings down a small quantity of

The Science of the Soil 99

carbonic acid gas from the atmosphere with it. It falls on the earth and
washes away fine particles from the hill and mountain sides into the plains
and valleys. The mountain stream often becomes a torrent, and tears away
great boulders, churning one against another, until they become rounded
and worn away. The streams become rivers and eventually flow into the
sea, and on their course they bring down masses of sand and silt, and
deposit it in the lowlands. Many soils have been made in this way, and are
said to be alluvial, because they have been washed on to a soil perhaps
of a totally different nature.

Running water not only performs this work, but also gradually dis
solves particles of rocks into a fine powder and wears away the face ot
them. This is called denudation. Water also fills the chinks and crevices
in the rocks and carries out the same work slowly but surely. Being com-
posed of the gases oxygen and hydrogen, and having a little carbonic acid
in it, certain combinations with minerals and metals take place. What
applies to rain and river water applies also to dew. If a piece of steel
or iron is left in the open air for a night it soons turns rusty. This shows
that the oxygen in the dew or rain has eaten into or combined with the
steel or iron and produced rust. This eating away of metals by atmos-
pheric gases is constantly going on, and in a few months a bright knife
will be almost worn away by their action.

Rain is not merely a combination of the gases oxygen and hydrogen;
it also contains small quantities of nitrogen and ammonia, chlorine, and
sulphuric acid. From the Rothamsted experiments it has been proved that
from 3'30 Ib. to 4'84 Ib. of nitrogen and ammonia is distributed over an
acre of ground during the year; and it sometimes happens that a small
annual rainfall will produce a larger supply of these gases. Chlorine equal
to 25'3 Ib. of common salt, and 17 '41 sulphuric acid per acre, have also been
found in the annual rainfall at Rothamsted.

Frost. This is a powerful agent in producing a powdery soil. When
water in the soil or in the crevices of hard rocks becomes frozen, it swells
up and occupies more space. In cultivated soils the particles are easily
pushed asunder, and are often raised up a good deal. In the case of rocks
the force exerted by the swelling ice is so tremendous that it is irresistible.
The rocks are therefore forced apart, splitting along the line of least resist-
ance, and when a thaw sets in great pieces are broken off. Fresh surfaces
are thus exposed to the weather, and the process of disintegration goes
steadily on.

Heat. This has the effect of warming the soil, and water in it, causing
both to expand and one of them (water) to evaporate. As water is driven
out of the soil in this way air enters, and thus makes the soil warmer than
it was before. As the temperature of the air varies greatly between mid-
day and midnight, sometimes as much as 60 F., one can readily imagine
a kind of opening and closing or expanding and contracting movement
going on continually on the crust of the earth, much in the same way
that the tides rise and fall, although not so conspicuous. This variation of

IOO

Commercial Gardening

temperature has its effect in splitting up the soil into smaller particles. Of
course the temperature varies according to altitude, season, and climate, but
it seems to be universal that night temperatures are always lower than day
temperatures.

The temperature of the soil itself, as distinct from that of the air, varies
according to the nature of the soil and the depth at which it is cultivated.

All heat is derived from the sun,
and the gardener seeks, in tem-
perate climes at least, to secure
as much as possible for his crops.
Thus he likes to have his land
with a gentle slope between the
south-east and the south-west,
because a larger surface is thus
exposed to the direct rays of the
sun. Even on level ground, if
he is wise, he will always arrange
his rows of fruit trees and bushes,
Potatoes, Lettuces, Tomatoes,
Peas, Beans, &c., running as near
north and south as possible, so
that the sun shall shine in be-
tween the rows at midday to
warm the soil about the roots.
If the rows run east and west,
one will shade the other, with
the result that the soil will have
a lower temperature, the effect
of which is less feeding activity
of the roots.

The annexed diagram, from
The Standard Cyclopcedia of
Modern Agriculture, shows the
variation of temperature in
clayey, sandy, and chalky soils.
It will be noticed in each case
that the temperature of the soil
at 4 ft. deep is always higher than that of the soil at 1 ft., and higher than
the air, during the first three months of the year (January, February,
March), and (in the case of clay and sand) during the last four months
of the year (September, October, November, December). During the other
months, April, May, June, July, August, the soil at 4 ft. deep is gener-
ally several degrees cooler than the air. The diagram shows the variations
for the three soils.

Wind. This plays an important part in the formation of soils. It
sweeps over the surface, taking away the moisture from it, and in dry

Air Temperature

Soil Temperature at I foot deep
. Soil Temperature at 4 feet deep

Fig. 84. Variation of Temperature in Clayey, Sandy, and
Chalky Soils

SALPIGLOSSIS

(Three-fourths natural size)

The Science of the Soil

IOI

weather the fine particles of dust and grit are borne from one place to
another, together with leaves, twigs, and other organic material. Fresh
surfaces are thus laid bare again for the action of rain, frost, snow, &c.
Vegetation. It is thought that in the early stages of the earth's career
only the lower forms of vegetable life could find a footing on its surface.
The various Algae, Lichens, Mosses, were able to pick up a living at first.
In due course they died, and their remains mingled with the surface soil,
thus gradually bringing about a compost suitable for the growth of higher

plants

" Dissolve to dust and make a way
For bolder foliage nursed by their decay ".

And so on, from one stage to another, one class of plants succeeding
another, and some even being crushed out of existence altogether, as we
learn from the fossil remains found in coal seams, shale, &c.

Animals, when they came, helped also to make our soils, and, like the
primitive plants, many of these died out under the stress of competition
from newer races. Worms also play an important part in the ventilation
of the soil, and wherever very large numbers are present it may be taken
as a sign that the subsoil is in a wet and heavy condition, and should be
trenched or at least double dug.

These natural soil-forming agencies, although of the greatest importance,
are nevertheless too slow for horticultural and agricultural purposes. If
a farmer or a gardener waited until the rain, frost, snow, heat, cold, and
wind, fec., converted a heavy clay soil into a fertile condition, he and his
race would soon become extinct. He therefore hastens the process of dis-
integrating various rocks and soils by such cultural operations as ploughing,
digging, trenching, manuring, &c. He " tills " the ground, and by ever
exposing fresh surfaces to the natural agencies of the weather, he, more
or less quickly, brings the soil into a condition capable of bearing large
crops of cereals, fruits, flowers, and vegetables. This condition is known
as fertile, whereas a soil that will not respond to such operations is known
as sterile.

5. CULTURAL OPERATIONS

Ploughing*. Although regarded as being almost entirely an agricul-
tural operation, many market gardeners also adopt this method of breaking
up their open land, and often even use the plough between fruit trees and
bushes when space permits.

Ploughing itself requires a good deal of skill on the part of the work-
man. A good ploughman will not only adjust the implement in such a way
as to place as little strain as possible upon his horses, but he will also per-
form more good work in a given time than an unskilled or slovenly worker.

In ploughing, the surface soil only is broken up to a depth of 6 in. or
8 in., the width of each furrow being about 10 in. on an average. The cost
of ploughing an acre of ground is about 15s., but it may be more or

102 Commercial Gardening

less according to the nature of the soil. From 1 to 1| ac. can be ploughed
in a day, and it is this facility for turning over the ground quickly that
has made ploughing more popular than spade cultivation. When the
ground is "subsoiled" a subsoil plough follows the other in the trench
and moves the lower soil to a depth of 15 to 18 in. The cost of subsoiling
1 ac. of land would be about the same as for ploughing, thus making the
total cost per acre for the two operations from 80s. to 40s. There are
many kinds of ploughs now in use, but all have the same object in view,
namely, to turn the soil up as well and as quickly as possible at the least
expense.

One of the latest inventions is an electric plough, invented by Mr. E. O.
Walker of Manchester. This is intended to supersede the steam plough,
wherever electric power can be procured easily and cheaply. Electric
wires overhead are used for a trolley as in tramcars, and the plough is
hauled across the field from one side to another as in the case of steam
ploughs. The same principles of shallow ploughing are adopted, but if

Fig. 85. iHagram showing Water (W) standing between Ridges in Land ploughed 6 in. deep

electricity or steam could be harnessed in such a way as to turn the soil
over to a depth of two or three feet, it would make a vast difference to the
fertility of the soil in the course of a year or two.

The great disadvantage of ploughing is that the soil is not turned over
to a great depth, and a hard pan is formed beneath the loosened layer. In
some soils this pan is so hard that it is impossible for air or rain to enter
the subsoil; and it is just as difficult, for the same reason, for the tender
rootlets of the plant to extend their search for food. All the fertilizing
advantages to be derived from the drying and warming action of the air,
the solvent effects of the rain, and the penetrating power of the roots are
thus rendered abortive, or at least greatly reduced. The diagram (fig. 85)
shows how the water after a heavy rain remains on the surface between
the ridges in ploughed land, until it is evaporated by the heat of the atmos-
phere and the wind. Under such circumstances the soil is cold and wet,
and cannot be worked, while the beneficial bacteria cannot come into
being in the soil until warmer and drier conditions prevail. The hard
pan brought about by repeated ploughings has been recognized as such an
evil by some American farmers, that they have taken the heroic measure
of breaking the subsoil up by charges of dynamite.

Digging. This operation is done with the spade or the fork. It is
a much better way of turning up the soil than with the plough. Not only
does the spade or fork go deeper, but the soil is turned over more com-
pletely, and the clods are broken down into much finer particles. An
expert workman will dig from 8 to 15 rods (about 240 to 450 sq. yd.)

The Science of the Soil

103

in a day, according to the nature of the soil. The cost of digging 1 ac.
of ground 1 ft. deep will vary from 40s. to 55s., more or less according
to the state of the soil and the rate of wages in different parts of the
Kingdom; and it will take one man from eleven to twenty days to perform
the work properly, and turning over from 70 to 120 tons of soil each day.

Digging consists in opening a trench one spit deep, the full depth of
the spade or the fork, and filling it with soil adjacent after lifting and
turning completely upside down.

Double Digging 1 . Double digging consists in opening a trench twice
as wide as in ordinary digging, and after the top spit has been removed,
the bottom is then broken up but usually left in the same position.
Manure is then added before the soil from the next top spit is placed on it.

Considering the depth of soil moved, the better breaking up of the
particles, and the enhanced fertility, it is a question if digging is not on the
whole a more economic method of cultivation than ploughing. One acre
of dug ground will produce better and more saleable crops than 1 ac.
of ploughed ground of a similar nature. The extra cost of digging is there-
fore more than repaid by the increased yield and value; in addition to
which must be reckoned the saving of half an acre's rent, the saving in
gathering the crop over a smaller area, and the saving in subsequent culti-
vation. This proposition may appear more feasible if stated in figures. If
an acre of ground dug by the spade or fork is only equivalent in yield to
1| ac. of ploughed land, one may take the ratio on a larger scale, as follows:

120 ac. ploughed

Rent at 2 per acre = 240

Ploughing at 15s. per acre = 90

330

80 ac. dug.

Rent at 2 per acre = 160

Digging at <2 per acre = 160

320

It is evident that if a man can get as much produce off 80 ac. as he can
off 120 ac., by a superior method of cultivation, he will be wise in adopting
the superior method. He will employ far more labour, and he will be
keeping men and their families on the land instead of keeping ploughs
rusting in his barns. The question of labour and its arrangement of course
requires careful consideration, so that the employees shall have work all the
year round at a regular wage; but this is merely a matter of organization.
The point for the commercial grower to consider is whether it will pay him
better to spend say 330 per annum in half -cultivating 120 ac. of land,
or whether it is more to his interest to spend 320 ten pounds less
in properly cultivating 80 ac. and reaping better results.

What is known as "bastard trenching" is taking out one spit of soil,
and then taking up the loose soil or " crumb " at the bottom and spreading
it over the top. Work like this will cost about 6d. per rod, i.e. 4 per acre.

Trenching". This operation can only be carried out where there is a
good depth of soil. Hence in hilly or mountainous districts, where only

IO4

Commercial Gardening

a few inches of soil rest on hard rock beneath, trenching and even double
digging is often out of the question.

When trenching ground, the soil is marked out in strips about 3 ft.
wide, and the first trench is taken out to a similar depth. Before the
soil adjacent is thrown into the trench in front it is a good plan to place
a good layer of weeds, green vegetable refuse, twigs, &c. in fact all
coarse and untidy vegetation at hand in the bottom. The only refuse
to avoid putting in the trenches is Potato haulms and the clubbed roots
of cabbage crops. These should be always burned to destroy the spores
of the terrible diseases which often afflict them. Having prepared the
first trench in the way indicated, the next piece of ground is marked off
3 ft. wide, and the soil from this, spit by spit and layer by layer, is placed
in the trench, until this is of course filled up, and a new trench is along-

VII VIII IX

''////////////////MM

III

VII

VIII

AC B

Fig. 86. Diagram showiug how ground may be trenched 3 ft. deep, bringing the bottom layer to the
top to be fertilized by the weather, and to allow the free passage of air, rain, and roots downwards.
Shaded portions indicate layers of manure. Note how trenched soil A is raised higher than the un-
trenched B. shows how soil has been dug out and placed at A. In B the figures 1 to 9 show how the
soil is to fill the trench in the same way as at A.

side. Where plenty of refuse and manure are available it will pay to
place a layer between the spits, keeping the best and most rotted manure
for placing beneath the top spit. A kind of sandwich of soil and manure
will thus be formed, as shown in the diagram (fig. 86).

Very few, if any, commercial gardeners adopt this system of culti-
vation, partly because of the cost of labour and manure, and partly because
they fear that it would be one of the greatest mistakes possible to bring
up the subsoil from a depth of 3 ft., and place it on the surface, especially
if it happens to be of a clayey, sticky nature, or of gravel. But it would
be well to remember the words of Virgil:

" Well must the ground be digged and better dressed
New soil to make, and meliorate the rest".

One can appreciate the argument against trenching on the score of ex-
pense; but if it is going to be done there will be no more, or very little
more, expense or labour attached to bringing up the bottom spit and
exposing it to all the fertilizing influences of the weather. As a rule
this is the case. There is only one possible danger, and that is if the
subsoil should contain a large proportion of ferrous oxide or protoxide

The Science of the Soil

105

of iron. This is distinctly unfavourable to plant growth, and is often
met with in yellow clay soil; but, as already stated at p. 97, it would
be foolish to choose a soil of this nature in the first place. This poisonous
ferrous oxide must not be confused with ferric oxide or peroxide of iron,
which is a valuable constituent of the soil. It promotes vegetation and
the development of the green colouring matter in leaves, and performs
other useful functions.

Even if one is so unfortunate as to have a soil containing much poison-
ous ferrous oxide, the best way to remedy this defect is by bringing up
the bottom soil and exposing it to the action of the weather. One of the
most important changes that takes place is the absorption of oxygen from
the air by the ferrous oxide,

W n > 1 I

which in the course of time be-
comes converted into the useful
and fertilizing ferric oxide.

The cost of trenching soil to
a depth of 3 ft. will vary from
8 to 12 per acre, an appalling
item apparently to a man with
limited capital; and then manur-
ing, hoeing, &c., must be added,
so that the cost of deep cultiva-
tion may well average 9 or 10
per annum per acre if vegetable
crops only are to be grown.
Against this great expense, how-
ever, must be placed the follow-
ing advantages: (1) An abundance of available plant food; (2) earlier,
heavier, and more remunerative crops; (3) abundance of warmth and
moisture at the roots in the hottest of summers; (4) lack of insect pests
and fungoid diseases; (5) saving in insecticides and fungicides; and (6) an
absence of weedy vegetation and a consequent saving in plant food.

If it is intended to grow fruit trees and bushes, it would be even more
wise to trench the soil to a good depth at first before planting, because
once fruit trees are planted it will be afterwards almost impossible to
rectify any troubles in the soil without incurring great expense. To bring
soil into a proper condition for fruit culture, it may be advisable to crop
it with Potatoes, Cabbage crops, Jerusalem Artichokes, Celery, Parsnips,
&c., the roots of which would penetrate the soil deeply and break it into
finer particles.

When digging, double digging, or trenching, it will be found convenient
to divide the ground into convenient portions, as shown at a, b, c, d (fig. 87).
By dividing each portion, as shown at ef. into two sections, a good deal
of labour and wheeling will be saved. The soil from the first trench,
6 to /, when taken out, may be placed in front of the section efcd at fd
When the work has reached ae, the trench there is to be filled with soil

Fig. 87. Diagram showing how the Ground may be
marked out for Digging or Trenching

io6 Commercial Gardening

taken from e to c. The work then proceeds to fd, and the soil which has
been wheeled there from bf is used to fill the last trench.

Ridging 1 Up. This is an excellent cultural operation, and is almost
equal in value to double digging. By digging a piece of ground length-
ways, the soil from the trench is placed on the adjoining soil to the right
or left, thus forming a ridge about 2 ft. high on one side and a trench
correspondingly deep on the other. If the base of the ridge be 2 ft. wide,
soil to cover one-half of it is taken from one side, and to cover the other
half from the other side. In this way heavy soil is brought up, and a
large surface is exposed to the weather. The soil in the bottom of the
trenches on each side of the ridges may be still further improved by
breaking up with the fork. A modification of ridging is to turn up a
" spit " of soil and invert it in same place. The next spit is taken up and
placed on top of the first, thus making a hillock and hollow alternately.
Soil that has been ridged up in winter will be beautifully sweet and mellow
in spring, when the crests of the ridges may be easily levelled down with
a fork before sowing or planting operations.

Raking* and Harrowing*. The rake is to the horticulturist what the
harrow is to the agriculturist. They both have the same object in view
namely, to level the surface of the ground, and break the clods into powder
so that it may be easier and better for the sowing of seeds. The rake is
useful for small areas, but the harrow (of which there are several varieties)
is adapted for drawing over large areas. The heavier harrows are useful
in clearing off the weeds, as are also the chain harrows, while the lighter
ones are used in connection with seed sowing.

Rolling*. This is also a horticultural and agricultural operation. Its
object is to crush the clods still further, to make the surface more level,
and to compress the particles sufficiently to hold moisture and make a
firm root run. It would be fatal to growth to have large fissures in the
soil, or to have it so loose and spongy that tiny seeds would sink down
so deeply that the seedlings would never be able to reach the light.
Rolling ground, or treading on it with the feet, therefore, has the effect
of packing the soil particles together, without making them adhere so
closely as to prevent the entrance of air and water.

Hoeing*. The hoe does not receive from the farmer or gardener the
respect to which it is entitled. It is kept lying idle very often until the
land becomes foul with weeds that have robbed the land of much of its
food and moisture (see p. 116) that will cost more to replace than half
a dozen hoeings.

The hoe should be in constant use while the crops are growing. It is
invaluable as a food producer, a weed killer, and a moisture conserver,
and when used with regularity the cost of hoeing an acre of ground,
even by hand, is not great, perhaps 8s. to 10s. or 12s. at the most. When
the soil has become overrun with coarse weeds, and the surface is also
baked, the cost of hoeing an acre may be anything from 20.9. to 30.s\

The material advantages to be derived from regular hoeing are:

The Science of the Soil 107

1. The upper crust is kept in a finely powdered condition. 2. Weeds are
unable to grow and rob the soil of food and water, nor the air of carbonic
acid gas. 3. By pulverizing the soil, fresh mineral foods are liberated
for the roots by the action of the weather. 4. In hot seasons the freshly
moved soil acts as a mulching and prevents the moisture escaping (see
p. 123). 5. The dews are absorbed at night and are soaked down to the
upper rootlets with fresh food. 6. The use of the hoe, especially during
the summer months, prevents many insect pests from nesting in the soil,
and the chrysalides of others are brought to the surface for the benefit
of the birds. 7. As large supplies of food are liberated by the hoe, there
should be a corresponding saving in the chemical manure bill, and as water
is conserved, there is not only a better crop, but it also comes to maturity
more quickly owing to the accelerated growth.

Taking these advantages into consideration it would pay every market
gardener to keep his ground regularly hoed from February or March to
October, and the money spent on it would be refunded over and over again.

6. THE BEST TIME TO WORK THE SOIL

Whether the soil is to be ploughed, dug, or trenched in spring or
autumn will depend largely upon its nature. Generally speaking it is
better to turn up heavy soils in the autumn and light soils in the spring.
As heavy soils contain a larger amount of dormant food than light soils,
and as it takes longer to transform them into a soluble condition, it is
better to have them ploughed, dug, or trenched during the autumn and
winter months. Fresh surfaces are thus exposed to the action of the
weather; clods are crumbled down into powdery masses by the action
of frost, rain, snow, wind, &c.; the air enters more freely between the
particles, and sourness and acidity are driven out by the sweetening action
of the atmospheric oxygen. The soil thus becomes "sweeter"; it also
becomes warmer, because better drained, and owing to the action of the
carbonic acid in the air, and arising from decomposing manure, supplies
of potash, phosphoric acid, nitrates, and other valuable foods become
available by spring. At this period also the over-harsh clods are easily
broken down by the rake or harrow, and can be rendered sufficiently
fine for the reception of seeds of various crops.

If "light" land is ploughed, dug, or trenched in autumn precisely the
same beneficial results would follow, but much more quickly. This would
be a distinct disadvantage to the farmer and gardener at this season.
Having no growing crops on the land to take up the freshly liberated
food, there is a danger that this would be washed down into the lower
layers out of reach of the roots. Thus, when sowing and planting time
arrived in spring, although the soil would be easily worked, it is possible
that the upper layer would be much poorer in plant food than it was
before the autumn breaking up.

io8 Commercial Gardening

The cultivator therefore must always pay attention to the physical
or mechanical condition of his soil rather than to its chemical composition,
and he must regulate his operations accordingly. It may be stated as
a good general rule, that whenever a crop is ready to be placed on the
soil, it is a good plan to have it dug in advance whether it be spring,
summer, or autumn.

7. PLANT FOODS IN THE SOIL AND AIR

By means of experiment it has been proved that all green-leaved plants
at least require certain essential foods to enable them to perform their
functions properly. Some of these foods are absorbed from the air under
the influence of sunlight, and some are taken from the soil by the roots.
These essential foods are

Nitrogen . Potash Iron

Phosphorus Lime Soda

Sulphur Magnesia Chlorine

Silica.

These thirteen foods are found in all plants in varying proportions. The
first four are gaseous and organic, and are driven from the plant by
burning. The other nine are found in the ash of plants, and constitute
the mineral or inorganic foods. When soluble in water, they are in a
condition to be absorbed from the soil under favourable conditions.

Until about three hundred years ago it had been always thought that
the soil supplied all the foods of plants and made up the great bulk of the
tissues. Jean Baptiste van Helmont (b. 1577, d. 1644), a chemist of
Brussels, was the first to disprove the old theory that all plant foods came
from the soil alone. He planted a young Willow weighing 5 Ib. in a pot
containing 200 Ib. of soil. He watered the plant daily with rainwater, and
grew it for five years. He then weighed the plant and soil again and
found that the Willow had increased from 5 Ib. to 169 Ib., but the 200 Ib.
of soil had lost only about 2 oz. Van Helmont therefore concluded that
the extra 164 Ib. weight of the Willow came from the water alone. In
this he was wrong. He did not know that the invisible carbon in the
air had anything to do with the increased weight of his W T illow. Indeed
it was not until a Dutch scientist, Jan van Ingenhuisz, published his
researches in 1779 that it was discovered that the increase in weight was
due to the carbon that had been assimilated from the atmosphere by the
leaves during the daytime (see p. 44). It is evident, therefore, that only
a very small proportion of plant food is actually taken from the soil itself.
That little, however, is absolutely essential; and unless it is in a form
easily dissolved in water, so that it may be absorbed by the roots, it is
quite useless, and no growth can take place.

The figures on p. 109, compiled chiefly from Dr. A. B. Griffith's works,

The Science of the Soil

109

FRUIT CROPS ASH ANALYSES

Name of Crop.

Potash.

Phosphoric
Acid.

35
|

H .

3 T3

1
*J

Magnesia.

o
02

Chlorine.

Apple, wood ...

19-24

4-90

63-60

0-93

1-66

7-46

0-45

1-31

Apple, fruit ...

56-21

10-89

4-87

3-05

1-93

6-53

14-02

0-68

2-82

Pear, wood

55-00

13-93

7-99

5-73

1-20

5-42

8-69

0-52

1-52

Plum, wood ...

56-99

12-09

6-39

3-33

5-21

9-25

5-24

0-20

1-30

Cherry, wood ...

21-63

7-56

30-24

2-62

8-72

1-84

0-81

24-96

Cherry, fruit ...

51-37

14-62

7-64

5-03

3-21

5-28

1-14

2-10

9-61

Peach, wood ...

52-61

13-69

4-88

3-21

1-20

4-10

11-89

0-55

7-71

Apricot, wood...

54-88

13-86

3-52

2-95

1-71

3-85

10-57

0-60

7-85

Apricot, fruit ...

60-20

12-00

4-26

3-06

1-26

2-12

9-68

0-45

6-91

Greengage, wood

58-09

13-99

9-81

3-62

5-00

6-28

0-12

0-61

2-48

Strawberry

41-40

11-70

12-21

3-15

11-14

2-93

1-29

2-78

12-05

Tomato, plant...

27-00

18-28

12-10

4-86

3-96

8-21

10-39

2-54

12-36

Tomato, fruit ...

53-04

14-53

4-38

0-92

3-97

Cucumber, plant

39-34

19-66

6-57

6-5(5

1-40

3-28

9 : 83

6-56

8-20

Cucumber, fruit

51-71

13-10

6-98

5-70

0-75

4-50

4-19

9-66

3-41

Grape vine

37-48

9-20

43-88

3-61

1-08

1-05

1-33

1-65

0-72

Gooseberry

38-65

19-68

12-20

5-89

4-56

5-85

9-92

2-58

Damson

45-98

13-83

12-65

2-37

1-19

8-17

5-66

9-22

Fig

28-36

1-30

18-91

6-75

1-46

9-21

26-27

5-93

VEGETABLE CROPS ASH ANALYSES

Name of Crop.

Potash.

Phosphoric
Acid.

e
21

id
fl

||
*j

CD
I

Chlorine.

Cabbage

31-95

12-93

15-66

8-61

8-32

4-93

2-51

7-99

4-99

Cauliflower . . .

34-39

25-84

3-07

11-16

3-67

2-38

14-79

2-78

1-92

Turnip

50-12

16-41

13-02

6-95

0-32

2-00

3-62

6-32

1-21

Kohl-rabi

48-69

16-75

13-65

6-82

0-48

3-18

3-89

5-31

1-23

Radish

23-65

40-12

8-92

6-97

2-10

3-64

3-01

3-59

8-00

Peas ...

20-10

40-10

6-90

2-00

1-40

8-90

17-30

1-20

2-10

Beans

42-50

34-66

6-00

3-50

0-40

7-30

3-34

1-40

0-90

Carrots

48-20

18-43

13-86

6-30

0-35

3-71

2-68

5-21

1-24

Parsnips

47-10

19-25

14-62

7-21

0-40

3-63

2-00

4-10

1-66

Celery

22-07

11-58

5-58

2-66

5-82

3-85

Beetroot

49-11

15-26

8 : 82

7-00

0-22

7-23

4-83

6-18

1-33

Lettuce

46-26

8-21

6-24

5-36

0-21

2-15

6-08

5-49

20-00

Endive

37-62

3-21

12-02

5-92

0-29

2-13

11-00

2-03

24-78

Rhubarb

30-00

18-13

14-21

5-04

3-68

7-33

9-78

2-03

8-06

Onion

32-35

15-09

13-66

8-34

12-29

2-70

8-04

4-49

3-04

Asparagus . . .

6-01

18-51

4-39

4-13

3-31

3-03

34-21

12-94

13-47

Jerusalem ^
Artichoke ) '"

44-62

14-97

8-36

5-21

4-31

6-89

9-63

2-98

13-03

Potato, tubers

55-75

12-57

2-07

10-62

0-52

5-28

1-86

7-10

4-23

io Commercial Gardening

will give some idea as to the various mineral foods taken out of the soil by
different fruit and vegetable crops. These foods must be all soluble in
water, and the temperature of the soil must be favourable, otherwise the
roots would be unable to absorb them. It will be noticed that the same
food is taken up by different crops in different proportions, and there is
often a great difference in the composition of the wood and the fruit on
the same plant. It should also be stated that the results obtained by
different chemists vary greatly, probably owing to the plants tested being
taken from different soils and at different times.

The quantity of these foods to an acre may be seen from the follow-
ing analysis of Broadbalk Field, Rothamsted. The soil had not been
manured for fiity years, and at 9 in. deep the weight of an acre was
2,500,000 Ib. containing

Carbon ............ 22,250 Ib.

Nitrogen ...... ... 2,500

Soda ............ 1,500

Potash ............ 6,750

Magnesia ......... 9,000

Lime ............ 62,250

Alumina ......... 112,250

Oxide of iron ......... 85,000

Phosphoric acid ... ... 2,750

Sulphuric acid ... ... ... 1,250

Carbonic acid ... ... ... 32,500

Total ... 338,000

This particular soil lost about 4'20 per cent, or 105,000 Ib., on ignition;
12'53 per cent, or 313,250 Ib., was soluble in hydrochloric acid; and the
undissolved siliceous matters were 83'27 per cent, or 2,081,750 Ib.

These figures would indicate that there is an inexhaustible supply of
food in the soil far more than could be absorbed by many crops in the
course of several years.

It has been estimated that an acre of fruit trees would require each
year about 200 Ib. lime, 150 Ib. potash, 75 Ib. nitrates, 50 Ib. phosphoric
acid. It would thus take over 311 years to exhaust all the lime in the
Broadbalk Field at Rothamsted, 45 years to exhaust all the potash, 33
years to exhaust all the nitrogen, and 55 years to exhaust all the phos-
phoric acid. And it must be remembered that these quantities are given
for an acre of ground unmanured for 50 years, and taken from only 9 in.
deep.

In an American experiment, soil at 1 ft. deep (not 9 in.) gave
3,225,000 Ib. weight to the acre, and was estimated to contain

Phosphoric acid ... ... 6,772 Ib. per acre.

Potash I... ....... 32,897

Lime ......... ... 47,407

The Science of the Soil m

An average of the results of forty-nine analyses of typical soils in
America showed that the first 8 in. of surface soil contained

Nitrogen 2,600 Ib. per acre.

Phosphoric acid ... ... 4,800

Potash 13,400

In a good Hertfordshire soil analysed by Dr. Voelcker the following
quantities of plant foods were found:

Phosphoric acid ... 4,569 Ib. per acre (over 2 tons).

Potash 10,483 ( 5 ).

Lime 74,188 ( 33 ).

Magnesia ... ... 9,676 ( 4 ,. ).

Sulphuric acid ... 4,569 ( 2 ).

Nitric acid ... ... 22

Nitrogen 2,397 ( 1 ton).

The surface soil from 9 to 12 in. deep is usually regarded as being
more fertile than the subsoil beneath. Although farmers may accept
this statement, many modern gardeners question it, for experience proves
that by turning the soil over to a depth of 2, 3, and even 4 ft. mag-
nificent crops can be secured. Indeed this has been proved for centuries
by Chinese and Japanese gardeners, who are adepts at deep cultivation.
Of course if the upper 9 or 12 in. of soil only are cultivated and man-
ured it is possible to prove that it is richer in available plant food than
the layers of soil immediately beneath. But actual practice proves that if
the subsoil is also cultivated and manured, and brought up to be acted
upon by the weather, it will gradually yield up the foods it contains.

The following comparison between the plant foods in the soil and
subsoil is worth consideration:

Subsoil.

53-71 per cent.

3-96

3-27

7-15

8-85

0-21

1-02

1-89

10-36

0-49

0-94

1-32
6-83

Surface Soil.

Silica, insoluble ..
Silica, soluble
Alumina ...
Iron
Lime

59-26 per cent
2-63
3-12
6-10
5-36

Magnesia...
Soda

0-02
0-93

Potash

1-53

Carbonic acid

7-00

Phosphoric acid ...
Sulphuric acid ...
Chlorine ...

0-13
0-63
1-20

Organic matter ...

12-09

100-00 100-00

With the exception of organic matter (which can be easily supplied

U2 Commercial Gardening

by means of stable manure and other vegetable and animal refuse) these
figures indicate that the subsoil really contains, on the whole, a larger
supply of plant food than the upper crust. Owing to the fact that the
latter is usually the only portion cropped it is not unnatural that it
should lose some of its available food and thus become poorer. Thus
one hears of a soil becoming "exhausted", by which is meant that it no
longer yields the same quantity of good saleable produce as formerly,
notwithstanding the fact that it has been cultivated and manured. The
" top spit", which is therefore usually regarded as the best soil, may be
really in a worse and poorer condition than the soil beneath it, owing
to constant cropping, and because it is "always carefully kept on top".

If any reliance at all is to be placed on the figures quoted above from
Dr. Voelcker and others, it is palpable that there is an enormous supply
of plant food locked up in the earth, and if it can only be made avail-
able not all at once, which would be fatal, but gradually the culti-
vator has but to work his soil properly to liberate this food.

But this is just where the chemical theorist fails and where the culti-
vator comes in. Jethro Tull and the author of the Lois Weedon System
of Cultivation were misled like many others with figures showing the
abundance of food contained in their soils, but in practice they failed
to obtain the best results. They practised deep cultivation, but they
overlooked the fact that something besides a good supply of mineral food
was also necessary. They overlooked the important factor of organic or
stable manure and humus generally. It is as true now as in the days
of Adam, notwithstanding our advance in the science of agricultural
chemistry, that the gardener or the farmer who would reap the best
results from his land must not only cultivate deeply, but he must also
" load his fallow ground with fattening dung".

8. HOW TO EXTRACT PLANT FOODS FROM

THE SOIL

Assuming that the soil contains the food supplies already tabulated,
the only way to bring them within the reach of any crop is by a rational
system of supplying organic manures (see p. 145) and by deep cultiva-
tion. This is apparently a costly method, but it is really more economic
than the prevailing system, as we shall endeavour to prove. In these
days there is a good deal too much quackery about supplying foods to
plants in a chemical and more or less unnatural form. Growers are
told they have only to give their soil a dressing of this, that, or the other
special manure, and their crops will be increased a hundredfold. There
is never a suggestion of cultivating the soil deeply (that would sound
too laborious), and the natural condition of the soil itself is rarely taken
into account; whether it be clay, sand, loam, or gravel the same manures
are recommended in all cases and under all circumstances. The result

The Science of the Soil

in many cases is that the grower spends his money uselessly and thought-
lessly, and his crops are a failure instead of a success. Here and there,
where the special manure happens by accident to suit the soil, good
results are secured. The grower is delighted. He pins his faith to that
particular brand, and uses it exclusively, until at length he finds that he
has ruined his soil and lost his money. This system of cultivation is on
a par with the methods of a man who seeks to keep himself in good
health by the aid of somebody's much-advertised pills, without taking
sufficient natural food or exercise. Sooner or later he becomes a physical
wreck (like the soil), and the pills (like the chemical manures) no longer
perform the miracles in his system they did when first used.

This view is borne out in a striking manner from the experiments on
Wheat at Rothamsted, an account of which has been published by Mr. A.
D. Hall in The Book of the Rothamsted Experiments, from which the
following figures are taken:

TABLE SHOWING THE AVERAGE PRODUCE OF GRAIN PER ACRE THE FIRST EIGHT YEARS
(1844-51), AND OVER THE SUCCESSIVE TEN-YEAR PERIODS

Plot.

Manures Applied.

8 Yrs.,
1844-51.

10 Yrs.,
1852-61.

rerages in

10 Yrs.,
1862-71.

Bushels

10 Yrs.,
1872-81.

af Grain c

10 Yrs.,

1882-91.

ver

10 Yrs.,
1892-901.

50 Yrs.,
1852-901.

Farmyard Manure

34-2

37-5

28-7

38-2

39-2

35-6

Unmanured

17-2

15-9

14-5

10-4

12-6

12-3

13-1

Minerals

18-4

15-5

12-1

13-8

14-8

14-9

Single Ammonium Salts and\
Minerals /

27-2

25-7

19-1

24-5

23-1

23-9

Double Ammonium Salts and")
Minerals ... ... /

347

35-9

26-9

35-0

31-8

32-9

Treble Ammonium Salts and )
Minerals ... ... /

36-1

40-5

31-2

38-4

38-5

36-9

Double Ammonium Salts alone

25-1

23-2

25-1

17-3

19-4

18-4

20-7

{

Double Ammonium Salts and \
Superphosphate ... /

28-4

27-9

21-7

22-7

19-5

24-0

{

Double Ammonium Salts and I
Sulphate of Soda ... /

33-4

34-3

25-1

30-1

26-7

29-9

Double Ammonium Salts and )
Sulphate of Potash ... /

32-9

34-8

26-8

32-5

29-6

31-3

,4{

Double Ammonium Salts and }
Sulphate of Magnesia /

33-5

34-4

26-4

31-1

25-0

30-1

From these figures it will be seen that, while the yield per acre from
farmyard manure steadily increased, except in one decade (1872-81), from
28 bus. of grain per acre to 39'2 bus., in every case of chemical manures
except the " treble ammonium salts and minerals " there was a conspicuous
and remarkable decline in the yield. All plots show a big drop for the
decade 1872-81, "a period of notoriously bad seasons", as Mr. Hall states.
A recovery then took place, but it was as marked in the "unmanured"
plot, No. 3, as in some of the others. Indeed the unmanured plot re-
covered more effectually than did Plots 5, 10, and 11. Comparing the aver-
age yields over the period specified, it will be noticed that while farmyard

manure shows an increase from 28 bus. in 1844 to 39 bus. in 1901, all the
VOL. I. 8

Commercial Gardening

others show a decrease, with the exception of the plot that had been man-
ured by "treble ammonium salts and minerals". The drop in yield is so
remarkable that it is worth while to state it in tabular form, thus:

Plot 2.

Plot 3.

Plot 5.

Plot 6.

Plot 7.

Plot 8.

Plot 10.

Plot 11.

Plot 12.

Plot 13.

Plot 14.

1st Year
50th Year . . .

+ Increase or)
Decrease /

bus.
28-0
39-2

bus.
17-2
12-3

bus.
18-4
14-8

bus.

27-2
23-1

bus.
34-7
31-8

bus.
36-1
38-5

bus.
25-1
18-4

bus.
28-4
19-5

bus.
33-4
26-7

bus.
32-9
29-6

bus.
33-5
25-0

+ 11-2

-4-9

-3-6

-4-1

-2-9

+2-4

-6-7

-8-9

-6-7

-3-3

-8-5

In Plots 2, 3, and 10 the experiments commenced in 1844; all the others
commenced in 1852. Plot 2 received farmyard manure, and shows an in-
creased yield of 11 '2 bus. per acre. Plot 3 was "unmanured", and at the
end of fifty-eight years shows a decline of 4'9 bus. per acre. It will be
noticed, however, that this decline is greatly exceeded in the chemically
manured Plots 10, 11, 12, and 14, which show a drop of 6'7, 8'9, 6'7, and 8'5
bus. respectively; while Plot 6, which received single ammonium salts and
minerals, only beat the " unmanured " plot by the skin of its teeth 4'1
against 4'9. Out of eleven plots, therefore, it appears that four plots (Nos.
10, 11, 12, and 14) had a much larger decrease in yield than the "unman-
ured" plot; while four others (Nos. 5, 6, 7, and 13) were almost as bad as
the plot that had received no manure at all.

Taking the highest yield that produced by the application of farm-
yard manure and the treble ammonium salts and minerals the yields of
39'2 bus. and 38*5 bus. are by no means remarkable. They are both under
5 qr. to the acre, so that at 2 per quarter the return is only about 10 per
acre for the grain. To this must be added the sale of the straw, averaging
from 34 to 40 cwt. per acre, making the gross return about 12 to 14 per
acre. From this must be deducted the cost of labour and manures, rent,
rates, and taxes, so that farming and manuring on the Rothamsted principle
would appear to be a very precarious business. The cultivation seems to
be of the poorest description; in fact it can hardly be described as cultiva-
tion at all. "The usual practice ", says Mr. A. D. Hall in his account of the
experiments, " is to scuffle the land immediately after harvest, and remove
the weeds; the land is then ploughed 5 or 6 in. deep; the mineral and other
autumn-sown manures are sown and harrowed in, after which the seed is
drilled." One can imagine the condition of the soil 6 in. from the surface
after fifty years of such " cultivation ". It must be almost as hard as rock,
and impervious to rain, air, or roots.

To obtain some idea as to what Wheat really could do if cultivated on
horticultural instead of agricultural lines, the writer carried out the fol-
lowing experiment at Ealing in 1910: Ordinary English Red and White
Wheat obtained from a flour mill 200 seeds of each were sown at a foot
apart each way on March 14. They germinated on April 9, and caused
some amusement owing to their scanty herbage and lonely appearance. By

The Science of the Soil

August the plants had tillered and grown fairly well, but were not con-
sidered satisfactory, although they averaged 2J to 3| ft. in height. On
September 24, the plants being sufficiently ripe were cut, and the following
results were tabulated: Out of the 400 plants, about 40 failed altogether,
that is 10 per cent. The best plant had 83 stems, and bore 45 ears of corn,
the gross weight of the plant being 2 Ib. Other plants had 50 stems and
37 ears; 39 stems and 36 ears; 37 stems and 17 ears; and the very poorest
had 24 stems and 11 ears, and a weight of 1 Ib. The average per plant for
the whole crop was 46'6 stems, 29*2 ears, and 1'45 Ib. Taking an acre of
wheat grown on these lines, there w r ould be about 40,000 plants, producing
an aggregate of about 2,000,000 stems and 1,200,000 ears of corn, having
a gross weight of nearly 26 tons, of which 19 tons may be regarded as
straw, and 7 tons as corn; or over 31 qr. of wheat per acre. By tilling
the ground deeply and well on true horticultural principles, there is no
doubt but that far larger supplies of wheat two, three, and four times as
much could be obtained from the acreage already under that crop. The
cost of producing it would be increased naturally, but taking an average of
four years' cultivation and manuring, it need not exceed an average of
9 10s. per acre per annum, apart from cutting. The cost of cultivating
wheat on horticultural lines, as indicated above, and the receipts, may be
estimated as follows:

EXPENSES PKK ACRE

RECEIPTS PER ACRE

1st year, Trenching 3 ft. deep ...

/ 160 bus. Grain = 20 qr. at 2 =
1 12 tons Straw at 2 =

40
24

2nd ,, Digging 1 ft. deep

( 176 bus. Grain = 22 qr. at 2 =
1 13 tons Straw at 2 =

44
26

3rd ,, ,, ,, ,,

/ 192 bus. Grain = 24 qr. at 2 =
1 14 tons Straw at 2 =

48
28

4th ,, Double Digging 2 ft. ...

/240 bus. Grain = 30 qr. at 2 =
1 16 tons Straw at 2 =

60
32

Hoeing twice each year at 25.s.

12 tons Manure each year at 5s.

per ton = 3

Balance 4th year . . .

264

302

To the average agricultural mind these figures may appear extraordi-
nary. If, however, it is possible to obtain 5 qr. of wheat year after year
merely by scuffling over the ground to a depth of 6 in., there is nothing
very remarkable in obtaining four and five times as great returns from
soil that has been deeply tilled, well manured, and thinly sown. After all
an average turn over of 75 10s. per acre is much better than 12 or 14,
although the cost of cultivation is greater on horticultural principles than
it is on agricultural ones. Once the land has been broken up, if the spade
and the fork and the hoe are substituted for the plough, not only would
wheat growing be revolutionized, but thousands of men would be kept on

Commercial Gardening

the land at better wages, and our wheat crops would be increased enor-
mously. Agriculturists would do well to consider the above figures before
smiling too broadly at them.

The annexed diagram (fig. 88) will show at a glance the great advan-
tages to be secured by deep tillage. At A, where the soil is dug out 1 ft.
deep, the roots are restricted; at B, showing soil dug 2 ft. deep, a larger
mass of roots develop and absorb more food; while at c, dug 3 ft. deep, a
still larger mass of roots search the soil for food, and no matter how dry

Fig. 88. Diagram showing the Root Development in Soil dug 1 ft. deep (A), 2 ft. deep (B), and 3 ft. deep (C).
The shaded portion shows the hard, impervious, and unbroken subsoil

the summer may be the tender feeding tips are always in the midst of
plenty of food and moisture.

9. WATER IN THE SOIL

Water, being essential for all plant growth, must be present in suffi-
cient quantity in the soil, and in such a condition that it can be absorbed
by the roots. Water may be in such abundance in some soils that its
presence would be more harmful than useful to the crop. Thus in a
clayey soil that has been only broken up with the spade or the plough
from 6 in. to 12 in. deep there may be so much water present that the
soil becomes chilled and waterlogged, and plants fail to grow because the
soil bacteria remain inactive (see p. 125).

The quantity of water in a soil depends upon the rainfall. This varies
in different parts of the United Kingdom from 24 or 25 in. in the
neighbourhood of London, and along the eastern counties of England
and Scotland, to 40 in. in the south-western districts; while in the
western Highlands, the Lake District, and parts of Wales the annual
rainfall is about 80 in. An inch of rain to the acre represents some-
thing over 100 tons of water to the acre; so that in the British Islands
the amount of water which falls upon an acre of soil varies from 2400
tons to 8000 tons annually. It penetrates the soil more or less readily
according to the nature of the soil itself, and the way in which it has
been cultivated, Thus on a clayey, uncultivated soil very little rain will

The Science of the Soil

117

pass straight downwards. It will flow away from the surface to the
ditches, or remain in pools in the shallow places -just as it does on
roadways and pavements. On a sandy soil, the rain will pass down and
between the particles readily until it comes to the water-table beneath;
and in loamy or peaty soils a good deal of water will be absorbed.

Different soils will absorb and retain water in 'different proportions,
as shown by the following experiment of Schiibler:

TABLE SHOWING ABSORPTION AND EVAPORATION OF WATER
IN VARIOUS SOILS

Water Absorbed

Evaporation in

by 100 Parts

4 hr. from 100 Ib.

of Soil.

of Water at 66 F.

per cent.

Ib.

Sand

Clay, loamy

Clay, heavy

Clay, pure ...

Rich garden soil ...

Peat mould

190

This is a laboratory experiment, and cannot therefore be regarded as
giving the same results as one would find in the open field, and in actual
practice. So much depends upon the way the soil has been treated.
Where the soil has been deeply dug or trenched far more water will be
absorbed than where it has been allowed to become hard and baked on
the surface. It therefore pays to cultivate the soil deeply and well if
full advantage is to be taken of the rainfall, and if the soil is to store
up sufficient moisture for the roots of the crops during hot and rainless
summers.

The above table teaches the market gardener that a soil which has
been well dressed with organic material like stable manure, peat-moss
litter, &c., will absorb and retain moisture for a very long period but
only in accordance as to whether it has been cultivated to a great or
little depth. That is the important point for practical growers to bear
in mind. Unless the soil has been well opened up by digging, trenching,
or subsoil ploughing, it will lose its moisture very rapidly, and crops will
suffer intensely in consequence during a hot dry season.

How Moisture is Lost. Soils lose moisture in four ways: (1) by
natural evaporation from the surface; (2) by bad and shallow cultivation;
(3) by transpiration from the leaves of the crops grown; and (4) by the
leaves of weeds allowed to grow.

The loss by natural evaporation will depend upon the temperature of
the atmosphere and the dryness or otherwise of the season. The higher
the temperature and the drier the atmosphere the greater the evaporation
from the surface. This is so well known to gardeners who grow pro-
duce under glass that special care is taken to counteract the heat and

Commercial Gardening

dryness by saturating both soil and atmosphere with moisture with the
hose or water pot. The only market gardeners who do the same thing
in the open air in a systematic manner are the intensive cultivators or
maratchers in France and Holland. British fruit-growers and market
gardeners, owing to the large areas they crop, find it physically impos-
sible to apply sufficient moisture to their crops; hence they suffer great
losses in dry seasons.

The diagram (fig. 89) will give an idea as to how water either rests
on the surface of the soil if hard and caked, or how it sinks down to
a depth of 1, 2, 3, or more feet if the soil has been broken up to such a
depth. It is obvious from the diagram, in which the soil has become
hard and baked, or is of a clayey nature and uncultivated, that most of
the rain that falls remains on the surface, and will be soon evaporated.
In the diagram, where a similar soil has been cultivated and turned up
more or less deeply, more water will sink into the soil, and it may be
taken that the powers of absorption will be as stated on p. 120, according

A B C

Fig. 89. Diagram showing Soil dug 1 ft. (A), -2 ft. (B), and 3 ft. (c) deep at the shaded portions.
The unshaded portions show the hard, impervious, and unbroken subsoil

to the nature of the soil. The deeper, therefore, a soil is cultivated, the
more moisture it will hold for the benefit of the crops.

LOSS Of Water through the Leaves. In addition to the water lost
by natural evaporation and by shallow cultivation, a vast loss is sustained
owing to the moisture that is given off from the leaves of the crops.
Stephen Hales (b. 1677, d. 1761) was the first to discover that leaves gave
off moisture, and an account will be found in his Vegetable Staticks, or
Experiments on the Sap of Vegetables, published in 1727. The quantity
of water taken out of the soil by various crops is stated by H. W. Wiley,
in his Agricultural Analysis, to be as follows per acre:

Equal to Inches

Crop.

Lb.

Tons.

of Rain

per Acre.

Wheat

409,832

= 183 nearly

1-83

Clover

1,096,234

489

4-89

Sunflower

12,585,994 =

= 5619 nearly

56-19

Cabbage

5,049,194

2254

22-54

Grape vines ...

730,733

326

3-26

Hops ...

4,445,021

1984

19-84

The accuracy of these figures may be doubted. If an acre of Sun-

The Science of the Soil 119

flowers, for instance, required 5619 tons of water (equivalent to 56 in. of
rain) to mature, it is obvious that they could not be grown in many
parts of eastern Great Britain, where the total annual rainfall only averages
24 or 25 in., or 2400 to 2500 tons per annum. As the Sunflower crop
would require only about 150 days at the most to mature, from start to
finish, something like 38 tons of water (or '38 in. of rain) would have to
fall on an acre of ground each day. Assuming that 10,000 Sunflowers
were grown to the acre, this would mean that each plant would absorb
and transpire about 8J Ib. of water per day.

Professor Bentley, in his Manual of Botany, states that "a common
Sunflower, 3^ ft. high and weighing 3 Ib., gives off on an average 20 oz.
of water; and a Cabbage plant about 19 oz. of fluid in a single day".

It may be remarked that a Sunflower 3| ft. high and weighing 3 Ib.
is a poor specimen. Taking an average specimen, 6 ft. high and about
6 Ib. in weight, it bears about 30 leaves, each with a superficial area of
about 45 sq. in. The total transpiration leaf surface for one Sunflower is
therefore about 1350 sq. in. Assuming that a plant of this size will trans-
pire only 24 oz. of water per day for 150 days, each plant will transpire
in the season 225 Ib. of water from its leaves, or over 1000 tons for a crop
of 10,000 plants to the acre. Assuming also that each plant, when fully
grown, contains 4 Ib. of water, that would give 40,000 Ib., or about 18 tons,
more moisture taken from the soil. It would therefore appear that an
acre of Sunflowers would require about 1020 tons of water (equal to 10 in.
of rain) in the course of the year.

The figures on p. 120 give an idea as to the approximate quantity of
water taken out of the soil during the growing season by various crops.

It will thus be seen that such crops as Sunflowers, Jerusalem Arti-
chokes, and Cabbage crops require at least 10 in. of rain in 150 days to
enable them to flourish, while Beetroot and Lettuces require over 23 in.
of rain, and Runner Beans require about 26 in. in the course of about
100 days. If all the rain that falls is not absorbed by the soil, it is evident
that the crops must suffer, unless moisture can be kept round the roots in
some way.

Mr. A. D. Hall, in his book on The Soil, calculates that 300 Ib. of
water transpired is equivalent to 1 Ib. of dry matter. It is obvious that
the amount of water given off will depend largely upon the season, whether
wet or dry, hot or cold, and also upon the way the crops are cultivated,
and whether they are planted at proper distances apart, and are in a
free-growing healthy condition, free from insect pests and fungoid dis-
eases. The nature of the crop itself must also be taken into account.
Some plants containing very little dry material (e.g. Lettuces, Turnips)
would give off more moisture than others of a more woody nature. And
again, some very fleshy plants, like most of the Cactaceae, many of the
Euphorbiaceae, and of the Asclepidese (like Stapelias, Haworthias), and
such plants as Stonecrops, are specially adapted to conserve their moisture
even in the hottest weather, owing to the very few stomata on their

1 20

Commercial Gardening

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The Science of the Soil 121

surfaces. Many of these are protected from the glaring sun by hairs,
spines, bristles, or by a waxy "bloom", consequently the amount of
moisture given off from their surfaces is very small.

Movement of Water in the Soil. We have already seen (p. 118) that
the deeper a soil is cultivated the more water it will absorb, no matter
what its character may be. This water sinks down and down until it
comes to a level where water is always standing. This water level or
water table may be from 3 to 150 ft. beneath the surface, and may be
taken to represent the reserve supply locked up in the soil. It is obvious
that all the rain that falls does not reach the water table, because it is
waylaid en route and absorbed by the particles of soil. And it must be
remembered that although more rain falls in the hilly districts, the soil
on the hillsides is not moistened so deeply as that in the lowlands and
valleys. In the latter places, apart from the natural annual rainfall, a
good deal of extra water is obtained when the rivers and streams overflow
their banks at floodtime. When the fields and meadows are flooded to a
depth of 1, 2, or 3 ft., many hundreds of tons of water are thus spread
over the land, and a very large quantity of it must sink downwards to the
water table if the soil is in a porous condition.

Water Lost by Weeds. Many growers do not appreciate the quantity
of water that is stolen from the soil by weeds. After all, weeds are plants
outcasts of the horticultural world, but they must live, if allowed to
remain on the ground. Being more vigorous in their nature than culti-
vated plants, they need large supplies of moisture to keep them going,
and they transpire through their leaves at least as freely as do cultivated
crops. It therefore follows that if an acre of ground, carrying, say,
40,000 Lettuces or 10,000 Cabbages, is allowed also to carry a crop of
weeds between, the amount of water taken up from the soil and evapo-
rated in the course of the season will be probably twice as great as if
no weeds were allowed to grow. The commercial gardener should there-
fore decide whether it is cheaper and better for him to allow weeds to
grow and steal the moisture and food from his Cabbages, Carrots, Beets,
Lettuces, and fruit trees or bushes, or whether it is more remunerative
to spend money in keeping the weeds down, and thus conserve the mois-
ture and food for his crops. The sensible grower will, of course, spend
money in labour for hoeing by hand or machine between his crops, because
he knows he will not only keep his crops clean, healthy, and steadily
growing with the moisture he is conserving, but also because he knows
that freshening up the surface of the soil means more food for the roots
of his plants, fewer insect pests in the soil, greater absorption of rain and
dew, and consequently crops that are likely to sell more quickly and fetch
higher prices than those that have been neglected.

During the summer months it is not at all uncommon to see the ground
between rows of fruit trees and bushes, and between vegetable crops, full
of weeds. These are not only robbing the air of carbonic acid gas (see
p 108). but also the ground of moisture, and leaving it in a parched and

122 Commercial Gardening

cracked condition. The weeds also harbour the grubs of various fruit
and vegetable pests that sleep in security until nature calls them forth
again to plague the grower who despises knowing anything about
them. The prevalence of weeds, therefore, in any garden indicates a
penny-wise saving in labour and a pound-foolish extravagance in other
directions.

The Upward Movement of Moisture in Soils Capillary Attraction.
We have seen that according to the nature of the soil, and the depth
to which it has been cultivated, large or small quantities of water are
absorbed and sink to certain depths. If, however, the water were to sink
so low as to leave no moisture at all in the root region, plant growth would
be impossible. We know, however, that in all well-cultivated soils there
is generally a good supply of moisture available, even in the hottest and
driest of summers. Whence does it come? Obviously from the supplies
deep down below the surface.

The soil may be looked upon as a kind of sponge. It will not only
soak in water from overhead, but also from beneath. Consequently we
find that when no rain falls, and the weather is hot and dry, a good deal
of moisture is rising from the ground. This is easily proved by placing
a piece of glass on the surface of the soil. After a short time it will be
noticed that the under surface is covered with moisture that could not
escape through the glass. If we dig down for 2, 3, or several feet
we see no actual water, but we notice that the soil becomes more moist
the deeper we go, until eventually we should reach water. It is evident,
therefore, that the moisture rises upwards, and passes from particle to
particle of the soil. A kind of invisible stream of vapour is constantly
rising from the lower regions, and is given off from the surface of the soil
into the atmosphere. This upward stream of moisture or vapour is caused
chiefly by the evaporation that is going on from the surface owing to the
heat of the sun. The top layer of soil particles are the first to lose their
moisture, then the next layer, and so on downwards, until, if no rain falls,
and the reserve of water beneath fails, the soil becomes as " dry as dust ",
and the crops collapse.

The ascent of water or moisture in the soil is much the same as it
would be in a sponge or in a slab of salt or sugar. The lowest layers in
direct contact with the liquid are more saturated than those above them,
and the particles composing the different layers have the power of drawing
moisture from those immediately below them. According to the nature of
the soil this power of raising the water from below upwards varies greatly.
Thus, in a heavy clay soil, where the particles are closely pressed together,
it is very difficult for the moisture to rise freely. The surface layers lose
their moisture after a time, and then, because they are unable to obtain
a supply from those beneath, the surface begins to shrink and crack and
form fissures in all directions.

In a sandy soil, where the particles, although closely packed, are no<
cemented together as in clay, moisture is given off very freely, and the

The Science of the Soil 123

upper crust very soon becomes dry and hot, and almost incapable of sup-
porting any plant life.

In a loamy soil, however, which is a mixture of sand, clay, and
organic material, moisture arises neither too quickly nor too slowly. It is,
therefore, retained round the roots for a longer period.

The ascent of moisture depends not only upon the nature of the soil,
but also upon the way in which it has been cultivated. We find even
in good garden soils that have been dug only 9 in. or 1 ft. deep, that
the moisture soon vanishes from this upper layer. The subsoil beneath
is probably too firmly compressed to allow the moisture to travel upwards
freely. The same thing is seen in soils that have been ploughed year
after year. The upper layer of 6 in. or 9 in. rests upon a very hard
" pan ", through which water can neither penetrate downwards nor rise
upwards.

If, however, we take a soil that has been broken up to a good depth,
say 2 and 3 ft., it will be noticed, even in the hottest and driest
summers, that there is always sufficient moisture available for the roots of
the plants growing on it, and they appear to be as fresh and green as if
they were supplied overhead with abundance of water each day.

The way in which the water passes upwards from layer to layer and
particle to particle of the soil is known as capillary attraction. The
direction of the liquid is always from the wet to the dry, and the finer the
particles of soil, and consequently the narrower the interstices between
them, the greater the height to which the moisture will rise.

This may be demonstrated by taking some glass tubes with bores of
various diameters. If placed on the surface of w^ater it will be noticed
that the liquid will rise higher and more quickly in the tube with the
smallest bore.

It is possible also that the pressure of the atmosphere has something
to do with this ascent of liquid in the soil. The air spaces between the
particles may be regarded as so many fine-bored tubes, up which the water
passes. Owing, however, to the heat at the surface, the air and the mois-
ture become warmer and lighter, and rise upwards. A kind of vacuum is
thus caused, or at any rate both air and moisture are less dense than at
a lower depth. The equilibrium between top and bottom is thus upset,
and the water and air from beneath rush upward, owing to the pressure
of the atmosphere, to fill the vacuum caused, and to restore the balance.
During a hot day this process is going on vigorously, and moisture rises
to the surface in the same way that oil is drawn up the wick of a lamp
by the heat of the flame at the top.

Every gardener who sows the spores of Ferns, or such fine seeds as
those of Gloxinias, Begonias, Rhododendrons, &c., takes advantage of the
capillarity of the soil, by dipping the seed pots in water, and allowing the
moisture to rise upwards to the surface instead of watering overhead.

Conserving- the Moisture in Soil The Use of Hoeing- and Mulching-.
While the aim of the open-air cultivator should be to prepare his soil

124 Commercial Gardening

for the reception of plenty of moisture and its ascent afterwards to the
roots of his crops, he must also take care that the supply of moisture does
not become exhausted during hot and rainless seasons. The experiment of
putting a piece of glass on the surface of the soil to collect the moisture
arising from it indicates a way in which moisture may be prevented from
escaping into the air from the soil. A piece of board or slate would act
in the same way as the glass, although the moisture would not be so
apparent. Indeed, layers of almost anything put on the surface of the
ground will check the moisture escaping from it freely. The cultivator
naturally wishes to keep the moisture in the soil, because it is the only
means by which the foods from the soil can be transmitted by root action
to all parts of the plant, and because it saves him the labour of watering.
Sheets of glass, slates, boards, &c., however, are not the most suitable
materials for keeping the moisture in the soil. The grower has found
that by placing a layer or mulching of more or less decaying manure on
the surface of the soil he not only prevents moisture escaping freely, but
he also prevents weeds from growing and robbing him of food and
moisture. In addition to this, as the manure gradually decays it yields
up to the soil certain valuable foods that are sooner or later washed down
to the roots by the rains. The manurial layer also prevents the sun from
scorching and baking the soil, and, being a bad conductor of heat, this is
a consideration in hot seasons. Layers of short grass, leaves, leaf mould,
moss, &c., would act in the same way as the manure.

When these materials are not available, it is still possible to conserve
the moisture by stirring up the surface of the soil to a depth of two or
three inches by means of the hoe or scarifier. At first sight it would seem
as if breaking up the surface soil would facilitate and accelerate the escape
of moisture from the soil beneath. Such, however, is not the case. When
the surface is broken up with the hoe a layer of loose soil is then placed
over the more consolidated soil beneath. In the latter the moisture is
rising freely; but when it comes in contact with the loose layer the particles
of soil in it are no longer so closely bound together that the moisture can
pass readily to them. Consequently a check to evaporation from the
surface takes place, and the moisture is kept in the soil for a longer period.
The loosening of the surface soil indeed produces a kind of soil blanket
which checks the rapid absorption of heat from the air, and the rapid
evaporation of moisture from the soil at the same time. The roots of the
crops are therefore kept in a cool, moist, and highly active condition during
the hottest seasons.

In some experiments carried out in America by Professor King on
a sandy loam, it was proved that in a hundred days the unmulched soil
lost water equal to 6*55 in. of rain, or 655 tons to the acre. When
mulched 1 in. deep, the soil only lost water equal to 3'30 in., or 330 tons
per acre; at 2 in. deep about 299 tons per acre; at 3 in. 254 tons per acre;
and at 4 in. 278 tons per acre. It would thus appear that a mulching
or loosening of a soil to a depth of 3 in. gives better results.

The Science of the Soil 125

It should not be forgotten that, apart from the benefits of retaining
moisture in the soil during a hot summer by loosening the ground with
the hoe, other advantages are also secured. The loose and more finely
powdered soil absorbs the dews more readily, inorganic foods are liberated,
and the grubs or pupse of various insect pests are brought to the surface
where they are readily pounced upon by the birds.

10. LIVING ORGANISMS IN THE SOIL

It has already been shown (p. 108) that mineral foods alone are
insufficient to supply all that is needed for plant life. Scientific investi-
gation has proved that the soil, if properly cultivated, is teeming with
life. Millions of minute organisms or bacteria are working away in the
dark converting the minerals and metals of the earth into plant food,
with the aid of the fresh air and the organic manures. This explains
why tons of stable or farmyard manure and vegetable refuse of all
kinds vanish after a time in the soil. It has been eaten away by the
bacteria, and in the process a certain amount of heat and fermentation
have been generated. This heat (more or less according to the condition
of the manure applied), in conjunction with a proper amount of moisture
and fresh air, dissolves some of the mineral substances, and brings them

into such a condition that they are readily absorbed by the roots. So
long as all the necessary factors are present the work goes on steadily;
but if one or the other is absent or in a poor state the whole work is
impeded. If lime, or manure, or both be absent no bacteria come into
existence and no changes take place. Hence a soil without them would
be as sterile as a heap of cinders or as the material in the roadway.

Nitrification. The most important work done by these soil bacteria
is to bring about the production of ammonium salts and convert them
into nitrates. These bacteria are most active at a temperature of 86 F.
(30 C.) according to some authorities, and at 98 F. (37 C.) according
to others, and become less active as the temperature rises above or falls
below these points. It follows from this that nitrate-producing bacteria
manufacture more plant food during the summer months, when the
temperature of the soil is about 20 degrees warmer than in winter.
This is just as it should be, for plants require far more nourishment
when in an actively growing state in summer than when in a compara-
tively inactive condition in winter.

This wonderful nitrifying process is perhaps brought to the highest
state of activity under glass at almost any season of the year. The
temperature is raised by artificial means, and plants are "forced" into
growth. This simply means that the bacteria respond to the higher
temperature and the moisture, and proceed to attack the substances in
the soil and place them more readily at the disposal of the crop. If the
temperature is suddenly reduced the plants are said to "catch a chill"

126

Commercial Gardening

' 2 3

Forms of Bacterial Cells
1, Coccus. 2, Bacillus. 3, Vibrio. 4, Spirillum.

a a' a"

o
b

OO
b"

and cease to grow. The sudden change from say 80 to 50 F. would
injure the active bacteria and put them completely out of action, with
the result that food supplies are immediately cut off from the plants.
One of the great problems the cultivator has constantly before him there-
fore is to maintain just the temperature to promote the greatest activity
amongst the soil bacteria. The grower under glass succeeds in doing
this often at a great cost; but the open-air grower must make use of
hot beds and plenty of good manure to achieve favourable results.

There are several kinds of
nitrate-forming bacteria in pro-
perly cultivated soils, amongst the
best known to scientific research
being Bacillus mycoides, B. mes-
entericus vulgatus, B. subtilis,
and Proteus vulgaris. With a
proper supply of organic manure,
a certain amount of lime to check
acidity, a genial temperature, and
a deeply worked soil these bac-
teria render valuable services.

In The Standard Cyclopcedia
of Modern Agriculture we are
told that "bacteria have a very
simple structure a speck of liv-
ing protoplasm surrounded by a
capsule or cell wall. They are
unicellular, and are the smallest
living organisms known, some
being less than a6 ooo in. in dia-
meter. Although there are hun-
dreds of different species, there
are only three general forms the
spherical (termed a coccus), the
rod-shaped (termed a bacillus),
and the spiral (termed a spirillum).
A curved rod is termed a vibrio." Professor W. B. Bottomley once
humorously classified the three kinds billiard balls, cigarettes, and cork-
screws. The diagrams (fig. 90) illustrate the various forms and the methods
of vegetative reproduction.

A single bacterium dividing in two, and taking one hour for the com-
pletion of the process, will in twenty - four hours produce 16,000,000
under suitable conditions. In ordinary cultivated soil the number of
bacteria varies from 300,000 to 10,000,000 per gramme of soil (100 gm. =
3'527 oz. avoir.). They occur in the greatest number in the first 6 in.
of the soil; below this they rapidly diminish until at a depth of about
3 ft. very few are to be found. Professor Hilgard, of the Calif ornian

ee
C"

C 1 "

Fig. 90. Diagrammatic Representation of the Methods of
Vegetative Reproduction among Common Bacteria

a, A bacillus successively dividing at a 1 , a", and a 111 .
6, A coccus giving rise to chains, &'" (Streptococci) ; pairs,
6 IT (Diplococct) ; and irregular groups, 6 V (Staphylococci).
c, A coccus giving rise by division in two directions to c 1 "
(ificrococci), and by division in three directions to c lv (Sar-
cince).

The Science of the Soil 127

University, states that in a black loam with a considerable amount of
humus there were 33,931,747 bacteria to 1 cub. cm., and as many as
53,596,060 in 1 cub. cm. of similar soil containing more humus. As there
are over 16 cub. cm. to 1 cub. in., and 1728 cub. in. to 1 cub. ft., one can
scarcely realize the teeming millions of bacteria there must be in a fertile
soil. Most cultivators will accept Professor Hilgard's figures to save the
trouble of counting them themselves. Speaking generally, the bacteria
may be classed into three groups: (1) The "decomposition" bacteria, that
attack and bring about the decay of manure and other organic matter;
(2) the "nitrifying" bacteria, consisting of two distinct organisms: the
one (a) Nitrosomonas, which converts ammonia into nitrous acid and
nitrite; the other (6) Nitrobacter, which changes nitrites into nitrates;
and (3) the "nitrogen-fixing" bacteria (Azotobacter), which absorb free
nitrogen from the air and fix it in the nodules of the roots of legu-
minous plants.

Soil Inoculation. It has been known from the earliest times that
leguminous plants (Peas, Beans, Clovers, Vetches, &c.) had a beneficial
effect upon cultivated soils crops of a different nature grew better
after a leguminous crop. But it was not until 1886 that Hellriegel dis-
covered how the nodules on the roots of leguminous plants were really
storehouses of nitrogen-fixing bacteria, and further investigations are
being made by other scientists.

Arising out of these discoveries Professor Bottomley conceived the idea
that, as the bacteria could be cultivated and isolated and kept for a long
time under certain conditions, it would be possible to " inoculate " a barren
soil a heap of slag or clinker even and bring it into a fertile condition
by the aid of these bacteria, and especially one called Bacillus radicicola.
In this way the "nitrogen famine", predicted by Sir William Crookes a
few years ago at a meeting of the British Association, was to be staved off.

Experiments in "soil inoculation" have been carried out more or less
carefully in several places, chiefly by non-cultivators, but it is not possible
to draw any definite conclusions from them. But one thing at least appears
to have been demonstrated by experiments carried out by Professor Nobbe,
of Germany, and that is, that the nodule bacteria are likely to become
overfed and lazy if there is already a good supply of nitrogenous food
at their disposal in the soil; whereas, if there is a deficiency, it excites
them into greater activity and virulence, exactly as if they were millionaires
on the one hand and peasants on the other.

The practical lesson to be learned from these investigations would
appear to be that (1) it would be a mistake to apply nitrogenous manures
to leguminous crops in any great quantity, as they would prevent the
healthy working of the bacteria; and (2) as the soil bacteria generally
are in greater numbers in the first six inches of soil, they could be utilized
to fertilize or inoculate the soil to a greater depth by trenching the soil,
and burying the top spit, containing the trillions of bacteria, lower down.
The subsoil rich in mineral foods (see p. Ill) but lacking in. bacteria,

128 Commercial Gardening

would thus become a medium in which the bacteria would exercise their
activity and virulence to the utmost. That is a far more simple and
expeditious method of inoculating the soil than cultivating the bacteria
in gelatine or powder. One crop of Broad Beans, French Beans, Clover,
or Peas would produce trillions upon trillions of nitrogen-fixing bacteria
to the acre in the top spit in the course of a season, and cultivators would
do well to bear this fact in mind.

Denitrification. This is the term applied to denote that the nitrates
in the soil have become changed into free nitrogen. The nitrates thus
become lost. Denitrification is said to be due to certain bacteria, just as
the production of nitrates is due to other bacteria. Curiously enough,
some scientists say that if air is admitted to the soil nitrogen is set free
from the organic matter; and, on the other hand, if air is excluded, nitrogen
is set free from the nitrates; and in both cases it is lost.

These views would appear to be mutually destructive. All good
cultivators know from experience the great advantages to their crops
arising from allowing a free circulation of air amongst the soil particles
and organic matter, and the more thoroughly these are mixed the better
the results. Growers of plants in pots always make a point of thoroughly
mixing the various ingredients of their special composts so as to secure
as much evenness or homogeneity as possible throughout. In field and
garden, however, this work, although possible, is rarely practised. And
it sometimes happens that enormous quantities of manure are dug or
ploughed into a soil which already contains a good and sufficient supply
of organic material. In such cases it is possible that, owing to the soil
being as it were surfeited or gorged with manure, certain bacteria attack
the organic material with the object of releasing the superfluous supply
of nitrogen. It has already been shown at p. 110 that even a soil that
has been unmanured for fifty years still has a fund of 2500 Ib. of nitrogen
to the acre at 9 in. deep just in the region where the nitrate-forming
bacteria are most numerous.

In support of the view that overdosing the soil with manure may result
in the loss of nitrogen, the following experiments at Rothamsted may be

quoted:

I. PLOT 7; RECEIVING AMMONIUM SALTS (CONTAINING
86 LB. NITROGEN AND MINERALS)

lb. per Acre.

Nitrogen originally present in 1865 ('1170 per cent) ... 3034
Nitrogen supplied in manure, 1865-93 ... ... ... 2408

Nitrogen supplied in rain, 1865-93 ... ... ... 140

Nitrogen supplied in seed, 1865-93 ... ... ... 56

Total nitrogen expected, 1893 5638

Nitrogen removed in crops, 1865-93 ... ... ... 1932

Nitrogen found in soil, 1893 (-1146 per cent) 2971

Total nitrogen accounted for in 1893 4903
Leaving nitrogen unaccounted for ... ... ... 735

5638

The Science of the Soil 129

II. PLOT 2B; RECEIVING DUNG (14 TONS, CONTAINING
200 LB. NITROGEN A YEAR)

Ife. per- Acre.
Nitrogen present in 1865 ('1752 per cent) ... ... 4,343

Nitrogen supplied in manure, 1865-93 5,600

Nitrogen supplied in rain, 1865-93 140

Nitrogen supplied in seed, 1865-93 ... ... ... 56

Total expected in 1893 10,139

Nitrogen removed in crops, 1865-93 ... ... ... 1,484

Nitrogen found in soil, 1893 (-2132 per cent) 4,976

Total accounted for in 1893 6,460

Leaving nitrogen unaccounted for 3,679

10,139

It would be difficult to find clearer examples of overdosing a soil with
food it did not require. In one case (Plot 7), leaving out the unavoidable
supplies from the rain and seed, 2408 Ib. of nitrogen were given to a
soil already containing 3034 Ib. Almost twice as much as the crop needed!
In the other case 5600 Ib. nitrogen were given to a soil still richer in the
same food (4343 Ib. per acre). But in this case, the greater the overdose
the smaller the quantity removed by nearly 500 Ib.

That the loss of nitrogen was due mainly to overdosing seems to be
still further proved by the experiment on the unmanured plot, the figures
for which are as follows:

PLOT 3; UNMANURED, 1865 TO 1893

Ib. per Acre.

Nitrogen originally present in 1865 (-1050 per cent), top 9 in. 2722
Nitrogen supplied in manure, 1865-93 ... ... ...

Nitrogen supplied in rain, 1865-93 140

Nitrogen supplied in seed, 1865-93 56

Total expected in 1893 2918

Nitrogen removed in crops, 1865-93 476

Nitrogen found in soil, 1893 (-0940 per cent) 2437

Total nitrogen accounted for, 1893 2913
Nitrogen not accounted for ... ... ... ... ... 5

2918

It would appear from these experiments that it is just as unwise to
give plants more food than they require in a given time as it is to gorge
animals with a certain diet. The system cannot absorb it, and the body
suffers in health in consequence. It would be interesting to have had
some information as to the cultural details carried out at Kothamsted,
the depth of culture, distance apart, and the yield per acre.

VOL. I.

Commercial Gardening

11. STERILIZING SOILS

Of late years growers of Ferns, Cucumbers, Tomatoes, &c., have been
much concerned as to the best means of rendering their plants immune
from attacks of eel worm and other pests. The soil has been regarded as
the seat of all the mischief, and various nostrums have been boomed as
infallible remedies against all the diseases that attack market crops.
At first some of these remedies appeared to check the disease, but after
a time the trouble was as rampant as ever. The only things that have
not been tried are cultivation and common sense. Soils have been brought

. O

into cucumber houses at great expense, and have been dosed with rich
organic and chemical manures to such an extent that acidity becomes
one of the predominant features. Under a high temperature, 85 to 95 F.
and more, and an excessively humid atmosphere, trillions of bacteria are
brought into being. Bearing in mind what has been said at p. 127 about
nitrate-forming bacteria growing lazy owing to having too much nitro-
genous food at their disposal, it is not to be wondered at that they fail
to perform those beneficial duties which they carry out in a soil con-
taining only a reasonable amount of organic material. Other bacteria,
no doubt, then come into play and doubtless devour the lazy ones, and
bring about such a condition of the soil that other troubles, like eelworms,
arise and play havoc with the roots of plants.

This being the case, the simplest plan would appear to be to keep
the soil from becoming acid by giving less rich food and more lime
the latter not only to counteract acidity, but also to induce the beneficent
bacteria to carry on their work. In addition to this, plenty of fresh air
must be admitted when possible, according to the state of the weather,
because the bacteria must have fresh supplies of oxygen to encourage
their activity. Many plant houses are so poorly ventilated that they
become "stuffy" with the stale atmosphere in them.

Burning- and Steaming- the Soil. Where a rational system of
cultivation is not practised, recourse is had to steaming or burning the
soil. Many growers of Ferns, for example, place the soil in receptacles
of some kind, and have it burned in the furnaces before sowing spores
upon it. The idea is that the excessive heat kills all the " bad " or un-
friendly bacteria and leaves the good or friendly ones intact. It has been
stated that bacteria are killed outright at 195 F., and that they cease
to work, and become comatose or unconscious, at 132 F. Consequently,
when soil is heated to 200 or 300 F. it follows that the bacteria must
be killed right out, and the soil reverts to a more or less sterile condition.
Because, in addition to killing the bacteria, if the heat is too intense all
organic material will be driven off also, leaving only the mineral substances
of the soil. This result can be achieved without burning, simply by crush-
ing pieces of brick or mortar, and sowing the spores upon them, as many
growers do.

A MIDDLESEX MARKET GARDEN AT DAFFODIL TIME

( 9 ) Photos, by Clias. L. Clarke

A CITY OF GLASSHOUSES AT WALTHAM CROSS, NEAR LONDON

The Science of the Soil 131

Steaming the soil would have rather a different effect from burning.
The bacteria would be killed, but the organic material would remain;
but whether it would retain all its nitrates and other foods or not experi-
ment only could prove.

Comparing the methods of growers who "sterilize" their soils with
those who do not, the latter produce at least as good crops as the former,
if not better, and without incurring further expense. Generally speaking,
if soils before use are well exposed to the action of the weather, and are
not afterwards overdosed with strong manures, they will continue to yield
excellent results.

12. ELECTRIFYING THE SOIL

From time to time scientists have turned their thoughts to the
question of electricity in connection with the soil and plant growth, and
numerous experiments have been carried out. The main object of these
experiments is to try to rob the atmosphere of nitrogen and convert it
into nitric acid, in the hope that plants will not only grow bigger and
better but much quicker than at present. The actual cultivation of the
soil itself on scientific principles does not appear to have been considered
in these experiments, all of which seem to aim at getting as much out
of the soil as possible without having recourse to physical labour. When
it is remembered that a man who digs 1 ac. of ground 1 ft. deep turns
over about 1340 tons of soil in 10 to 14 days (more or less) at a cost of
a couple of pounds, the idea of the "electrical" cultivator is apparently
to save this trouble and expense.

Amongst those who have already taken part in electrifying the soil are
the French priests the Abbe Berthelon and the Abbe" Nolet, the Swedish
Professor Lemstrom, and, more recently, Sir Oliver Lodge and Mr. J. E.
Newman, of Evesham. Under the Newman-Lodge method as The Times
describes it "the wire is taken from the dynamo to a shed in one of
the fields which are to be electrified. This shed contains apparatus for
transforming the electricity to high tension, and also the vacuum valves.
The network over the crops consists of a kind of gridiron of wire,
supported from each pole with larger insulators than those seen on
telegraph poles. The poles are 70 yd. apart in the rows and 100 yd.
apart between the rows. The thick telegraph wire is extended down
the rows, with thin wire to encourage leakage at every 10 yd. The
thin wire is invisible 20 yd. off. There is a slight fizz, caused by the
electrical discharge, and in walking beneath the wires a slight sensation
may be experienced. At night there is some glow. If a wire breaks'
this does not often happen anyone picking it up would receive an
unpleasant shock; but though there are obviously possibilities of electro-
cution in the high-tension shed, there is no risk to life in the field. The
apparatus does not supply a tenth of an ampere. The apparatus can

132 Commercial Gardening

be managed by a boy, but it is necessary to make sure from time to time
that there is no interference with the proper discharge of the electricity
due to leakage down damp poles or to defective insulators. An installation
of the simplest type, for experimenting on from 5 to 10 ac., a dynamo
being available, would probably cost about 100. In the same conditions
an installation for 60 ac. might cost about 225. A complete outfit
for 30 ac., including engine, dynamo, and shed, would involve an ex-
penditure of something like 300, but an installation for twice the area
would not cost more than another 100. There is a probability of the
expense being decreased in the future." It is claimed for this electrical
process that there is an increased yield accompanied by accelerated pro-
duction, and the plants (Lettuces have been chiefly experimented on) are
of a deeper green.

It is always wise to pay attention to experiments, even when carried
out by those who have had little or no training in horticultural prac-
tice, but we have no hesitation at present in saying that 6 or 8
per year spent on trenching an acre of ground 2 ft. to 3 ft. deep would
yield larger supplies of nitrates and crops immensely superior to anything
that can be achieved by " electrical " culture. [j. w.]

13. SOIL ANALYSIS

All growers, whether amateur or professional, are aware of the difficulty
of estimating just what form of plant food is deficient, and usually it is
only by more or less costly experiments that some basis can be obtained.
Of course many men simply depend on certain quantities, adding such to
the soil whether the plants require it or not, until soil sickness occurs, and,
in consequence, many pests and plant diseases.

To obviate the above disadvantage, and to obtain a useful knowledge
of the composition of the soil, analysis, both chemical and physical, is
resorted to, and it is proposed to deal with this in as simple a way as
possible. It must of course be thoroughly understood from the beginning
that to arrive at an accurate analysis requires much expensive apparatus
as well as a long course of practice and study, but enough information
will be given to enable the studious grower to obtain many useful data,
to save him from wasting his time over unnecessary experiments, and
also to open a new field for research and profit.

In the older methods of analysis the soil after preparation was digested
by strong acids, hydrochloric being the chief. This extracted all the food
that might or might not be available at some future period, but gave no
idea of what was immediately available for the plant's use. In conse-
quence of this the results were so misleading that soil analysis was spoken
of with scorn. Often enough one ingredient was said with truth to be
in large quantity, but the growing crop would show symptoms of starv-
ing for want of that very constituent. As an instance, clays and clay

The Science of the Soil 133

loams are usually designated as being rich in potash, yet the addition
of potash salts will often give high results on such soils, showing there-
fore a deficiency in available potash, an entirely different thing from total
potash.

Many of the food salts in the soils are so tightly held or combined
as to resist even long years of cultivation and weathering.

Nowadays it is the rule to dissolve out the available salts which can
be immediately rendered available to the growing crops, by using for this
purpose a 1- per -cent solution of citric acid; this strength having been
estimated to correspond with the solvent action of natural forces at
work.

These forces are the weak organic acids obtained from humus, the work
done by the beneficent and other bacteria, as well as by enzymes and
certain fungoid moulds, and, lastly, by the solvent action of soil water
impregnated with carbonic acid gas.

It is not at all necessary for anyone to attempt a complete analysis. To
obtain such would mean probably months of work, and the data obtained
would be of very little value to the grower. What is usually done is
to give the quantities of lime carbonate (chalk), magnesia, nitrogen, phos-
phates, potash, the total contents, organic matter and humus.

About 40 to 80 per cent of soil matter is inert and does not enter into
the fertilizing, but its composition determines the physical condition of a
soil and thus has a great bearing on cultivation.

In reading an analysis care should be taken to note that the magnesia,
usually magnesium oxide (MgO), is not in excess of the lime contents,
or disease and various other troubles will quickly follow. It will not
matter how much lime carbonate is present if the magnesium oxide is
multiplied by 2 and then compared with lime carbonate. Sufficient of
the latter must be added to give a proportion equal to four of the
former (magnesium carbonate) to seven of the latter (lime carbonate).

A sample of soil may be taken as follows: Cut a square about 9 in.
with a spade to a depth of about 1 ft.; take the whole of the soil from
this block and place in a box. Remove to a shed or laboratory for
examination.

If the soil is rather wet, allow it to air-dry somewhat, and then work
through a fine sieve to remove all stones. Take a portion of the soil, say
\ to \ lb., and place in a beaker, tube, or even an ordinary jug. Fill
the vessel containing the soil three parts full with water; stir to a paste,
thus separating clay from sand. Allow to settle somewhat, pour off, and
repeat this until the added water becomes no longer turbid. Remove
the sand from the bottom, air-dry, and weigh, and the result will show
you into what class your soil fits, whether it be sand, sandy loam,
loam, clayey loam, or clay, the physical constituents of which are given
at p. 92.

Chemical Analysis. The following is a minimum list of apparatus,
some of which may be evolved from ordinary articles in everyday use, but

134 Commercial Gardening

the majority will need to be specially designed, or accuracy in results
cannot be looked for:

1 balance. 2 filtering funnels, 6 in.

Palette knife. 1 stoppered cylinder, 750 cub. cm.

Beakers. 6 at 300 cub. cm. capacity. 1 desiccator

2 at 600 1 wash bottle for water.

1 Winchester quart for citric digestion. 1 alcohol.
C0 2 apparatus. 1 ,, ammonia.

2 Berlin porcelain dishes, 4 in. 1 ,, hydrochloric acid.
4 crucibles. 1 nitric acid.

1 distilling flask and condenser. 1 pestle and mortar.

1 closed vessel to supply steam, to 6 glass rods.

act as small boiler. 1 large sieve, 4 meshes to inch.

2 conical flasks with Bunsen valve. 1 small ,,16
2 burettes, 50 cub. cm. Filter stand.

1 pipette, 25 cub. cm. Water bath.
1 graduated measure, 500 cub. cm. oven.

1 100 Burette stand.
6 clockglasses. Filter papers.

2 filtering funnels, 4 in. 1 pair crucible tongs.

Lime Carbonate. The first constituent to be estimated will be the
lime carbonate in the soil. Proceed as follows: Place a small quantity
of soil in a test tube or other convenient vessel, such as a cup; fill up to
1 in. from bottom; pour over sufficient strong hydrochloric acid (commer-
cially known as spirits of salt) to cover the soil. If the soil contains a
reasonable amount of lime carbonate a vigorous effervescence will occur,
but if there is little or no disturbance then lime or lime carbonate must
be added to the soil at once. The chemical action is roughly as follows:
Hydrochloric acid (HC1) attacks the calcium carbonate (CaCO 3 ), driving
out carbonic acid gas and forming calcium chloride.

The more accurate method adopted by chemists is as follows:

To estimate the available constituents of the soil, 200 gm. are mixed
with 2000 cub. cm. of 1-per-cent citric acid solution and left for a week,
the whole being shaken up once a day. The solution is then filtered
and divided into separate portions of 500 cub. cm.

Phosphates. To estimate the soluble phosphates 500 cub. cm. are
evaporated until the volume is reduced to about 100 cub. cm. and then
allowed to cool, and 40 cub. cm. of ammonium molybdate solution added,
well stirred, and allowed to stand in a warm place. This is then filtered
and the precipitate washed, first with dilute nitric acid and then with
very small quantities of distilled water. The precipitate is then dissolved
in ammonium hydrate and 20 to 30 cub. cm. of magnesia solution added,
the whole being allowed to stand for twelve hours for complete pre-
cipitation. The resulting precipitate is now filtered off and washed with
dilute ammonia dried and incinerated in a crucible, the residue being

The Science of the Soil

135

weighed as magnesium phosphate. From the magnesium pyro-phosphate
obtained the weight of phosphoric acid can be calculated. One part of
magnesium pyro-phosphate = '64 parts of anhydrous phosphoric acid (P 2 O 5 ).

Total phosphates are estimated by treating 5 gm. of dried soil with
25 cub. cm. of concentrated hydrochloric acid, and evaporated to dryness
over a water bath. The residue is moistened with concentrated sulphuric
acid, then treated with a mixture of 10 cub. cm. of hydrochloric acid and
10 cub. cm. of water, warmed, filtered while hot, the filter paper being well
washed, and the filtrate treated with an excess of ammonia, boiled, allowed
to cool, and filtered. It is then redissolved in nitric acid and dried with
40 cub. cm. of ammonium molybdate exactly as indicated in the paragraph
above for soluble phosphates.

Potash. To estimate the potash a further 500 cub. cm. of the citric
acid solution are evaporated to dryness and incinerated in a basin over a
Bunsen burner to eliminate the organic matter. The residue is then treated
with boiling distilled water and filtered. An excess of platinum chloride
is then added to the filtrate, and the whole is slowly boiled until nearly
dry. The precipitate is filtered off and washed with alcohol until no yellow
coloration is to be seen in the filtrate. The least possible quantity of water
is then added, together with an excess of magnesium powder. The reaction
with this is completed by boiling. After cooling, the excess of magnesium
is dissolved in hydrochloric acid, the whole being filtered and the pre-
cipitated platinum, which remains upon the filter, is washed free from acid,
dried, and weighed. From this platinum is calculated the quantity of
potash present. One part of platinum = - 48 parts of potash (K 2 O).

Iron. Available iron is estimated in a further 500 cub. cm. of citric
acid solution, this being evaporated to dryness over the water bath, and
incinerated over a Bunsen burner to drive off the whole of the organic
matter. The residue is dissolved in hydrochloric acid, then evaporated
in a conical glass flask. The iron is reduced to the ferrous condition by
the addition of metallic zinc (adding only sufficient to get it into complete
solution), and titrated with a deci-normal permanganate of potash solution.
Each cubic centimetre of permanganate of potash required until permanent
coloration is produced indicates the presence of '008 gm. of Fe 2 3 or ferric
oxide.

Calcium Carbonate. This is estimated by 5 gm. of the dried soil
in a CO 2 apparatus, one portion of which contains a supply of hydrochloric
acid and a tube to enable it to be passed into the portion containing
the soil, and a further portion contains a tube filled with concentrated
sulphuric acid through which the escaping gases pass, in order to retain
in the apparatus any moisture that may tend to be carried away. In
this way the calcium carbonate is decomposed, the carbon dioxide being
evolved. The apparatus is then stood for a quarter of an hour on the water
oven to ensure the exclusion of the whole of the gas. The weight of
the whole apparatus being taken, with the soil in it, before commencing
the operation, it is now weighed again and the difference represents the

136 Commercial Gardening

loss of C0 2 gas. 44 parts of the gas represent 100 parts of calcium carbonate
that was present. This assumes that there is no magnesium carbonate
present.

Humus. In estimating the humus, 10 gm. of dried soil are taken
and washed on the filter paper with a 1-per-cent solution of hydrochloric
acid till free from calcium salts. It is then well washed with hot, distilled
water till free from acid, and washed into a long stoppered cylinder with
500 cub. cm. of 4-per-cent ammonia solution. It remains in the solution
twenty -four hours, allowing the cylinder to lie in as nearly a horizontal
position as is possible without allowing the stopper to leak, and is well
shaken at intervals. The cylinder is then stood upright for twelve
hours to allow the whole to settle to the bottom. The solution is then
filtered, and 100 cub. cm., representing 2 gm. of soil, are taken and
evaporated to dryness over the water bath. The dish is then placed in
the water oven for a few minutes, to dry off any adhering moisture,
and weighed. After weighing, it is incinerated until all the organic
matter has burned off. The dish is allowed to cool in the desiccator
and the weight again taken. The difference in the weights before and
after incineration gives the humus.

Magnesia. This is estimated by boiling 5 gm. of dried soil with 25
cub. cm. of concentrated hydrochloric acid, and evaporating to dryness over
a water bath. The residue is moistened with concentrated sulphuric acid,
then treated with a mixture of 10 cub. cm. of hydrochloric and 10 cub. cm.
of water, warmed, filtered while hot, the filter paper being well washed,
and the filtrate treated with an excess of ammonia, boiled, allowed to cool,
and filtered. The filtrate is neutralized with acetic acid and treated with
ammonium oxalate (about 20 cub. cm.) to remove calcium, and again fil-
tered. The filtrate is evaporated down and treated with successive 5-cub.-
cm. lots of concentrated nitric acid to eliminate ammonia salts. As the
liquid by this time has evaporated down to a small bulk, it is diluted to
about 200 cub. cm., treated with ammonium phosphate, and allowed to
stand for twelve hours. It is then filtered and washed with dilute am-
monia, dried in the steam oven, and incinerated in a crucible and weighed.
From the weight of magnesium pyro- phosphate obtained the magnesia
can be calculated as MgO. 1 part of magnesium pyro -phosphate = 36
parts of magnesia oxide. [c. P. c.]

SECTION V
Manures and Manuring

i. INTRODUCTORY

The word "manure" has now come to mean any substance that is
placed on or in the soil with the object of fertilizing or enriching it in
plant food. Originally the word meant " working with the hand ", having
been derived from the two French words main, the hand, and ceuvre,
work. There is a vast depth of meaning in the word "manure", if the
French derivation of it is accepted. Long before botanical or agricultural
science enabled man to understand the nature of his plants, and what they
required as food, the peasant who tilled his ground by hand was manuring
or " manoeuvring " it in the real sense of the word. And even to this day,
" working " the soil turning it up and exposing it to the weather is one
of the cheapest and best, if not the quickest, methods of adding fertility to
the soil.

Since, however, the great and illustrious Baron Justus von Liebig
(b. 1803, d. 1873) propounded his theories on agricultural chemistry some
seventy years ago, a vast change has taken place in the methods of
manuring. The chemist has stepped in, and as a result of his laboratory
experiments he has told the gardener and the farmer, but chiefly the latter,
what manures he must use if .he would wish to obtain the best results from
his soil. A vast industry has arisen in the shape of chemical or artificial
manure manufacture, and thousands have become impressed with the idea
that their salvation as cultivators depends entirely upon the amount of
"artificials" they apply to their soil. Indeed, there is very great danger
of the art of cultivation being lost altogether amongst the agricultural
community, and even amongst many market gardeners.

Cultivators of the soil should always remember the very old story of
the dying man who on his deathbed told his sons that they would find
gold deeply buried in the farm, and they had only to dig deep enough
to obtain it. At first the sons mistook their father's meaning, and it was
not until they had turned up the soil of the farm to a great depth, and
noticed the magnificent crops that followed, that they began to realize
the true meaning of their father's words. The gold came, not as they
expected, from the soil itself, but from the sales of their farm produce.

137

138 Commercial Gardening

If they had not tilled the ground deeply the gold would not have been
forthcoming in any shape or form.

This story conveys an excellent moral for all cultivators, and it
embodies the true principles of manuring principles that are strictly in
accordance with all we have learned about the composition of soils and
manures from the best scientific authorities.

Experiments at Rothamsted and elsewhere clearly prove that the soil
does contain vast supplies of some of the most important plant foods, such
as nitrogen, phosphates, potash, lime, magnesia, soda, iron, chlorine, silica,
&c. But what none of these experiments teach is that these foods can
be liberated and made available for the use of our various crops by cul-
tivation or " handworking '' the soil.

After all, it must be remembered that the agricultural chemist is not
a cultivator, although he may deduce from the chemical analysis of a
certain soil, or a certain plant, that such and such foods are required,
and that it is only necessary to supply them by means of some artificial
manure, and the plant will proceed to carry out its functions, and be
perfectly happy ever after.

If this were really the case, the art of manuring would be reduced to
the simplest mechanical process. A certain soil is found by analysis to be
lacking or deficient in one or more foods that we know to be essential for
the welfare of a certain crop. Therefore sprinkle over the soil or dig it
in a manure which is known to contain the necessary foods, and all will
be well at least it was thought so at first by Liebig and others. The
quantity of special fertilizer must be carefully regulated, otherwise the
plants, instead of growing, will probably die. Indeed the difficulty as
to regulating the quantities to be applied has only been overcome by
frequent experiment, and after plants had been killed by overdoses.

This is practically the basis upon which modern manuring is practised.
Either the soil is dosed with special manures, or certain crops are given
special manures, almost irrespective as to their growth, or as to the nature
and condition of the soil in which they are growing.

If these principles of manuring were sound, our cereal and root crops
ought to show a vast increase in yield and quality since farmers have
taken to using artificial fertilizers in such large quantities. But our
crops of wheat, oats, barley, rye, potatoes, turnips, beet, mangels, Swedes,
&c., appear to be no greater on the average per acre now than they have
ever been. Here and there, of course, are to be found exceptions that
prove the truth of the statement, but it will generally be found that these
exceptions are due more to good cultivation to the working, and cleansing,
and purifying of the soil than to the extensive use of artificial fertilizers.

This view receives confirmation from Prof. Snyder, of the University of
Minnesota, in his book on Soils and Fertilizers. He says: "Scant crops
are as frequently due to the want of proper tillage as to the absence of
plant food. Poor cultivation results in getting the soil out of condition;
then instead of thoroughly preparing the land, commercial fertilizers are

Manures and Manuring 139

resorted to, and the conclusion is reached that the soil is exhausted, when
in reality it is suffering for the want of cultivation, for a dressing of lane 1
plaster, for farm manures, or for a change of crops. There is no question
but what better tillage, better care and use of farm manures, culture of
clover, and systematic rotation of crops would result in greatly reducing
the amount annually spent for commercial fertilizers without, reducing
the yield of crops, as well as securing larger returns for the fertilizers
used. In general, the better the cultivation the less the amount of com-
mercial fertilizer required for average farm crops. Cultivation cannot,
however, entirely take the place of fertilizers."

The reader must not imagine that artificial manures are being abused.
From practical experience the writer knows their virtues very well, but
the point he wishes to drive home is that artificial manures, unless used
carefully and judiciously, are more likely to ruin a cultivator than to add
to his bank balance. They have their uses undoubtedly, and as adjuncts
to natural manures and cultivation they can be made to play a most
important part. Many experimenters and growers are beginning to realize
this now, and they take care to use a proper mixture of natural and arti-
ficial manures.

Misleading* Experiments. Perhaps the most misleading thing about
the application of certain manures in experimental gardens is that what
is found to yield good results in one particular soil may prove to be quite
useless on another soil. If the increased yield in a crop could be really
attributed to the application of a certain manure, the experiments would
be of immense value. A reference to the article on the " Manuring of
Potatoes", in Vol. IV, will, however, convince any cultivator that no real
reliance can be placed on a particular manure applied to any soil. It will
be noticed from the figures that the very manures which are claimed to
yield large crops in one county are the very same that give results even
poorer than the soil to which no manure at all has been applied. If it
is fair to claim an increase in yield for certain manures in one place, it
is equally fair to attribute a decrease in yield to the same manure applied
in another locality. And yet all manurial experiments are carried out on
this illogical basis. The only reliable thing about the application of special
manures is that results are true only for the particular place in which they
are obtained.

Another misleading method of applying manures is to assume, first
of all, that a certain crop requires certain manures, and must have them
at all costs. Take, for instance, such a crop as the Turnip, which is said
to take up 112 Ib. of nitrogen, 33 Ib. phosphoric acid, and 148 Ib. of potash
from an acre of soil. The uninitiated are apt to come to the conclusion
that large supplies of nitrates, phosphates, and potash must be applied to
the soil, no matter what its chemical or physical condition may be, when-
ever Turnips are to be grown.

Some laboratory experimenters, indeed, make a difference between
"light" and "heavy" soils, and recommend a variation in quantity of

140 Commercial Gardening

the manures which analysis has indicated as being essential for a certain
crop. It is, of course, possible that such recommendations will prove effec-
tive in certain cases, but that will be more by accident than design, and
will depend upon circumstances.

Before applying special manures to the soil the cultivator has to con-
sider, first of all, the physical nature of his particular soil; the amount of
manure, organic or otherwise, he has already given it; the crops grown
and harvested from it; and the system of cultivation practised, whether
deep or shallow. He must also remember that every cultivated soil, even
one that has not been manured for fifty years, like that at Rothamsted,
contains almost inexhaustible supplies of certain foods. His main object
ought to be to bring as much of this food supply as possible into use by
good and deep cultivation, and then to supply the deficiency (if any) by
organic or inorganic manures, or by both in certain proportions. This is
the wise and economic policy to pursue, and it will pay much better to
turn up the soil to a good depth than merely to scrape up a few inches
of the crust, which has been perhaps cropped over and over again for
years until it has become either sick or exhausted.

In business the grower must pay from 4 to 20 and more per ton
for special manures to supply food which probably exists in abundance
in his own soil if he would only liberate it. A ton of special artificial
manure, costing say 20, will dress from 3 to 7 ac. The same amount
of money spent in digging the soil 1 ft. deep would bring from 7 to 10 ac.
into a fertile condition, or, if double dug, from 3 to 5 ac., with more
lasting effects. The insoluble stores of nitrogen, phosphates, potash, and
lime that are locked up in it in the dark are likely to be liberated and
made available when brought up to the light and exposed to the action
of the weather. Indeed, in actual practice it is so, and the man who
turns his soil up most frequently and most deeply is the one who reaps
the largest and best crops at a minimum of expense.

The point, therefore, for the commercial grower to consider is, which
is better to spend more money on labour and get his plant foods out of
the soil, or to spend less money in labour and more in artificials and leave
the natural food supplies in the earth untapped for many years?

The Object of Manuring". The main object of manuring is to restore
to the soil, in a more or less available form, the foods that have been taken
out of it by the growth of crops. It is evident that if everything taken
from the soil were again replaced, there would be no loss at all. But if all
the crops grown were put back again, there would be far more material
returned to the soil than ever came out of it. There is still a popular
impression that the entire weight of a crop comes from the soil, and from
the soil only. The air and water get but very little credit for the important
part they play in providing, after all, by far the greater weight of every
plant. Water itself may be looked upon not only as the means by which
foods from the soil are drafted to all parts of the living tissues, but also
as a distinct food or manure, as it supplies both oxygen and hydrogen.

Manures and Manuring 141

Before we consider the application of manures to the soil it is necessary
to refer again to van Helmont's experiment with the Willow, already
described at p. 108. That experiment clearly proved that the great bulk
of a plant's weight came, not from the soil, but from the air and from
water. Carbonic acid gas (of which there are only 4 volumes out of 10,000
in the atmosphere) supplies all the carbon that is necessary, so long as
the cultivator is sensible enough to allow his plants sufficient space and
light, and does not overcrowd them. This carbon, which makes up the
great bulk of the dry weight of every plant, is obtained absolutely free
of charge from the air, and there is not the slightest danger of the supply
becoming exhausted. The carbon from the air and the water from the
soil make up from 95 to 99 per cent of the weight of all plants, thus
leaving from 1 to 5 per cent of material to be provided by the soil alone.
Perhaps this fact will be made more clear by the following analysis of
the wheat plant, taken from Sowerby's Thorough Cultivation:

COMPOSITION OF WHEAT PLANT

Per Cent.

Carbon 47 -69 "j 93 -55 per cent of the whole

Hydrogen ... ... ... 5 '54 j- = plant obtained from the air

Oxygen ... ... ... 40'32 J and water.

Soda 0-0

Magnesia . . .
Sulphuric acid
Chlorine
Oxide of iron
Silica

3 '386 per cent of foods, which
as a rule are present in large
quantities in the soil (see
p. 110), and have to be rarely
applied artificially.

Manganese 0'2S

3 '00 per cent of foods which
Nitrogen ... ... ... 1'60 "| the soil contains in limited

Phosphoric acid ... ... 0*45 I quantities (see p. 110), and

Potash ... ... ... 0'66 j which must be rendered

Lime ... ... .;. 0'29 J available by cultivation or

supplied by manures.

From this table it becomes evident that the art of manuring the soil
is narrowed down in a very remarkable degree. As with wheat, so with
other crops. The cultivator has not to concern himself with providing
oxygen, carbon, or hydrogen so long as he allows his plants plenty of
fresh air and a proper supply of moisture. He is actually relieved of the
burden of finding over 93 per cent of the material which makes up his
crops. The other 3*386 per cent, consisting of soda, magnesia, sulphuric
acid, chlorine, oxide of iron, silica, and manganese, he also very rarely has
to trouble himself about, as they are generally present in great quantities
in the soil. But he must remember that those inorganic foods can only
be liberated and brought into an available form by the constant use of
the spade, the fork, the plough, the hoe, &c.; in fact, by cultivation or

142 Commercial Gardening

tillage operations. If the soil is not cultivated, these foods remain dor-
mant, inactive, and insoluble, and therefore worthless to any crop.

Having 97 per cent of the bulk of his crop practically provided free
of charge, except for labour, the cultivator has to devote his energies to
supplying the other 3 per cent, made up of nitrogen, phosphoric acid,
potash, and lime. Now, the soil is by no means deficient in these foods.
In the Broadbalk Field, Rothamsted, it has been found that a soil which
had been cropped, but had not been inanured for fifty years, still contained
2500 Ib. of nitrogen, 2750 Ib. of phosphoric acid, 6750 Ib. of potash, and
62,250 Ib. of lime to the acre at a depth of only 9 in.

These figures are remarkable, and cultivators would do well to re-
member them. If a soil that has been cropped, but has been unmanured
for fifty years, still contains such large quantities of the most important
plant foods, it ought to follow as a matter of course that a soil which
has been cropped and has also been manured for the same period should
show far larger quantities of these particular foods. Such, however,
is not the case, as the experiments carried out at Rothamsted prove.
The addition of certain manures often has the effect of liberating too

freely some of the plant foods, and as they cannot be absorbed by the
crop, they are lost in some way, or at least cannot be accounted for (see
p. 128).

To appreciate all the factors in the case it is necessary to remember
what has been already emphasized, that only very small quantities of
nitrogen, phosphoric acid, potash, and lime are taken from the soil. It
has been estimated that fruit trees and ordinary farm crops take from
the soil from 50 to 100 Ib. of nitrogen, 20 to 50 Ib. of phosphates, 30 to
150 Ib. of potash, and 150 to 200 Ib. of lime. Comparing the figures with
the supplies still remaining in the Broadbalk Field at Rothamsted after
fifty years, and with the supplies that are said to be in a fertile soil, it
is evident that only small quantities are liberated as food for each crop.
The usual deduction made is, that as these supplies of nitrogen, phosphates,
potash, and lime are to be found in a soil after fifty years, therefore they
are regarded as unavailable and probably useless. This view seems to be
quite erroneous. Why should these vast supplies become immediately
soluble? Would it not be a dire calamity if they were to become so, and
if they vanished in one season? The result would be complete and abso-
lute sterility, and succeeding crops would have to starve. Apart from this,
it would be a physical impossibility for any crop to take up or absorb
62,250 Ib. of lime, 6750 Ib. of potash, 2750 Ib. of phosphates, and 2500 Ib.
of nitrogen altogether, 74,250 Ib. (over 33 tons) per acre. In a Turnip
crop weighing 33 tons, only about 2 or 3 per cent of the dry weight, say
from 1400 to 2000 Ib. would come from the soil, the remainder coming
mostly from the air and water.

In the Bulletin (No. 103) of the Cornell University, U.S.A., for October,
1895, the following interesting figures appear in connection with an experi-
ment on some Wagner Apple trees thirty-five to the acre.

Manures and Manuring

143

TOTAL WEIGHT AND CONTENTS OF ONE WAGNER APPLE TREE, THIRTEEN
YEARS OLD, AND OF THIRTY-FIVE SIMILAR TREES TO THE ACRE

Total Weight.

One Tree.

35 Trees to
Acre.

Ib.

Leaves

33-18

1161-3

Water

15-92

557-2

Dry matter ...

17-26

604-1

Nitrogen

0-29

10-15

Phosphoric acid

0-08

2-80

Potash ... ...

0-28

9-80

At the end of twenty years (the Apple trees being then thirty-three
years of age) it was computed that the amount of nitrogen, phosphoric
acid, and potash taken from the soil during the period of trial was as
follows:

Nitrogen.

Phosphoric
Acid.

Potash.

Fruit
Leaves

Total for 20 years ...
Average per year

Ib.

498-60
456-75

Ib.
38-25
126-00

Ib.

728-55
441-00

955-35

164-25

1169-55

47-76

8-21

58-47

These quantities are much less per acre per annum than those already
given above. They serve, however, to indicate the small amount of food
exhaustion that takes place, and incidentally the quantities of nitrogen,
phosphoric acid, and potash that might have to be supplied to maintain
the equilibrium of available foods in the soil. Assuming the figures to
be fairly accurate, it would appear that the fallen leaves, if dug into the
ground during the winter months, would supply, when rotted, about half
che entire quantity of food taken out during the year, as shown, thus:

Nitrogen.

Phosphoric
Acid.

Potash.

Ib.

Food taken from an acre
of soil each year
Food supplied by fallen
leaves per acre

Balance to be supplied
by cultivation and man-

47-76
22-83

8-21
6-30

58-47
22-00

24-93

1-91

36-47

ures per acre ...

The quantities of nitrates, phosphates, and potash taken out of an acre

I 4 4

Commercial Gardening

of soil each year naturally vary a good deal, according to the nature of
the crop. It will be seen from the table below that some crops absorb
much larger quantities of certain foods than others, and this fact should
be borne in mind when applying manures.

TABLE SHOWING IN BOUND NUMBERS THE QUANTITIES OF NITROGEN, PHOS-
PHORIC ACID, AND POTASH TAKEN OUT OF AN ACRE OF SOIL BY
VARIOUS CROPS'

Crop.

Nitrogen.

Phosphoric
Acid.

Potash.

Ib.

Fruit crops ...

150

Mangels, 22 tons

138

300

Beets, 14 tons

142

Turnips, 17 tons

112

148

*Turnips, 17

187

426

Swedes, 14

Beans (30 bus. grain))
and straw ... /

106

Oats, 45 bus. and straw

Wheat, 30

Barley, 30

Maize, 20

Potatoes (6 tons, tubers)

*Potatoes(6 ,, )

119

192

Meadow hay, 1| tons..

Red clover, 2 ...

102

Hops ...

200

134

*Cabbage

213

125

514

*Cauliflower ...

202

265

*Carrot

166

190

*Cucumber

142

193

*Lettuce

*0nion

*Pea

153

It will thus be seen that such crops as Mangels, Turnips, Beans, Red
Clover, and Hops absorb large supplies of nitrogen from the soil; and
Mangels, Turnips, Beet, and Hops also drain the soil of large quantities
of potash. It is noteworthy that such leguminous crops as Beans and
Clover should take up such large quantities of nitrogen, notwithstanding
the power they possess of fixing the nitrogen of the atmosphere (p. 127).

The figures for the crops marked with an asterisk are taken from
Professor S. W. Fletcher's book on Soils, and relate to analyses at the
Michigan Agricultural College. It would appear that according to the
climate, and no doubt the methods of cultivation, the quantities of food
taken from the soil would vary very much.

Manures and Manuring 145

2. KINDS OF MANURES

Long before agricultural chemistry was thought of there were practi-
cally only two kinds of manure in use farmyard or stable manure and
lime. These constituted the stock of the farmer and market gardener,
but other odds and ends were added to soil in the way of waste materials.
With the advance of botanical and chemical science, however, plant-growers
have been made aware of the different constituents of plants, and numer-
ous experiments proved that from twelve to thirteen different ingre-
dients (see p. 108) were always found in plants, and had to be supplied.
Of these the most important are the nitrates, phosphates, potash, and
lime. Hence manures are now classified in accordance with the amount
of food they supply as nitrogenous, phosphatic, potassic, and calcareous.
Natural manures supply all these foods in small quantities in proportion
to their bulk, but they must not be despised on this account. The
advantages of complete, bulky manures are discussed under the heading
of " Farmyard Manure " below, and these advantages exist to a certain
extent in all organic material placed in the soil for manurial purposes.
Artificial manures, on the other hand, supply large quantities in proportion
to their bulk of one or more fertilizers, and therefore have to be used with
caution. And they possess not only this disadvantage, but others. They
supply no humus to the soil, and consequently are incapable of generating
bacteria. Their application is often of what may be termed a purging
nature, because they liberate too freely large quantities of valuable foods
that cannot be absorbed by the roots of plants, and are therefore lost
either in the drainage or as gas that escapes into the air. Thus it may
happen that a soil, instead of being enriched by applications of chemical
manures, may be quickly impoverished and rendered sterile. In practice
this is actually the case when chemical manures are applied injudiciously
or indiscriminately.

From a practical standpoint it may be more convenient to consider
the various manures under the following headings:

1. Complete Manures. Those supplying not only nitrogen, potash, phosphates,
and lime, but also the other essential foods like sulphur, iron, magnesia, soda,
chlorine, &c.

2. Nitrogenous Manures. Those chiefly supplying nitrogen.

3. Phosphatic Manures. Those chiefly supplying phosphoric acid.

4. Potash Manures. Those chiefly supplying potash.

5. Calcareous Manures. Those supplying lime or chalk.

6. Miscellaneous manures, such as sulphate of iron, salt, &c.

VOL. I. 10

146 Commercial Gardening

3. COMPLETE MANURES

Farmyard Manure or Dung". This name is applied to solid and
liquid excreta from animals, together with the litter that has been used
for bedding down. Wheat straw is generally used for litter, but peat-
moss litter has of late years become a rival for bedding in stables. Other
materials, such as bracken, shavings, spoiled hay, &c., are used also; but
whatever material is used it becomes farmyard manure when it becomes
too wet with urine and too foul with droppings to be used any longer
for bedding. It is then taken outside and stacked in heaps. The urine
of animals being usually richer in nitrates, phosphates, and potash than
the droppings, every care should be taken to preserve it, not only for its
intrinsic value as a fertilizer, but because it is useful for keeping the
litter in such a state of dampness that it will not burn or turn mouldy.
Wheat straw will absorb about three times its own weight of liquid, and
peat-moss litter about eight times its own weight. It has been estimated
that a horse affords 1000 Ib. of urine annually containing 89 Ib. of solid
matter, and a cow 13,000 Ib. of urine containing 1023 Ib. of solid matter.
About 67 Ib. of solid matter is contained in 1000 Ib. of human urine; 21 Ib.
in 1000 Ib. of pig urine, and 30 Ib. of solid matter in 1000 Ib. of sheep
urine.

The quantity and quality of the excreta vary according to the kind
of animal, its age, and the food it eats. The droppings from cows and
pigs contain more liquid than those from horses and sheep. Hence the
"sloppy" manure from pigs and cows is termed cold, and is useful for
"hot" gravelly or sandy soils. Horse and sheep manure, however, is
known as hot, and is better applied to heavy or tenacious soils.

It has been estimated by a German scientist that a horse will excrete
28 Ib., a cow 73 Ib., a sheep 3'8 Ib., and a pig 8'3 Ib. per day, and that
these excreta mixed with straw litter will yield 33 Ib., 81 Ib., 4'4 Ib., and
12'3 Ib. of manure per day from each animal respectively. This estimate
is presumably for fully grown animals in a normal state of health.

Storing" Farmyard Manure. In most cases, perhaps, farmyard
manure is stacked or thrown loosely in heaps and left exposed to the
weather. Unless frequently turned over and kept moistened with water
or urine the manure heap will gradually allow the best part of its fertiliz-
ing ingredients, namely, the ammonia gas, to vanish into the air, a mis-
fortune readily recognized by the smell given off. Or the heavy rains
wash out all the soluble salts into the drains, where they are lost. The
result often is that the "life" of the manure has departed, and nothing
is left but the dead carcass. To avoid these calamities it is therefore
best to have the manure under cover if possible, and placed on concrete
bottoms, so that any liquid oozing out may be afterwards collected and
thrown over the heap. If a piece of moistened red litmus paper be placed
near a steaming manure heap it will turn blue] and a glass rod dipped in

Manures and Manuring 147

spirits of salts (hydrochloric acid) will be covered with a white crust of sal
ammoniac, produced by the union of the acid with the escaping ammonia.

Manure should be well packed or trodden down, as it loses ammonia
more readily if left in a loose condition, Wonderful chemical changes
take place rapidly in the heap, and micro-organisms are at work reducing
the organic material into a finer, less littery, and more fertilizing compost.
In this way the manure heap loses considerably in bulk, and the farmer
and gardener must take care not to let it remain too long before working
it into his soil. It has been computed that 100 loads of fresh dung left
exposed to the action of the weather loses nearly 27 loads in 81 days,
35^ loads in 254 days, 37 loads in 384 days, and about 53 loads (over
one-half) in 493 days.

Growers of flowers, ferns, palms, &c., use stable or farmyard manure
in fairly large quantities, but not of course so largely as market gardeners
and farmers; and many of them preserve all the ingredients of the manure
by stacking it in layers with soil. Thus a bed is marked out, and per-
haps a layer of soil 1 ft. thick is spread over it. On top of this a layer
of manure 3 or 4 ft. thick is placed. Then another layer of soil, followed
with a layer of manure, until the material is used up the top layer always
being soil. Arranged in this sandwich-like way, the layers of manure
decay evenly, and at the same time fertilize the layers of soil. In due
course the compost is chopped down with the spade, and is used in various
proportions with other soil for any special crops. While it may not be
always possible or convenient for market gardeners to store manure in this
way, those who cultivate plants of any kind in pots will find it an excel-
lent method of producing a rich and agreeable compost.

Value of Farmyard Manure. Farmyard manure is a bulky manure,
but in a good condition it is probably the best and safest of all manures,
natural or artificial. Although 1 ton of it only contains from 9 to 15 Ib.
nitrogen, 4 to 9 Ib. phosphates, 9 to 18 Ib. potash, and 39 Ib. carbonate
of lime, its fertilizing value must not be judged from these quantities
on the unit system applied to artificial manures like sulphate of am-
monia or nitrate of soda. While it is in itself a complete manure, con-
taining all the foods from the soil, water, and air, it possesses mechanical
advantages superior to any other manure. Being bulky, when dug into
the soil it pushes the clods asunder and allows fresh air and water to
enter freely. By its decomposition or fermentation heat is generated,
carbonic acid gas is given off, minerals and metals are rendered soluble in
conjunction with lime, and millions of bacteria are brought into being to
produce other foods in the soil. These important functions cannot be per-
formed or brought about by any chemical manure by itself, and it would
be courting disaster to use them exclusively on any soil.

The quantities of farmyard manure necessary to keep a soil in a fertile
condition vary according to the soil and its nature. On loamy soil in a
well -cultivated condition from 12 to 16 tons may be regarded as a fair
dressing. In a heavy loam, or clayey soil as it is often called, from 16

148 Commercial Gardening

to 24 tons to the acre would not be too much. And in light, sandy, or
gravelly soils, which are notoriously hot and hungry, from 30 to 50 tons
per acre would be hardly sufficient to obtain good results. It will thus
be seen that although a light sandy soil may be had at a very low rent,
this advantage will vanish completely when the expenses of manuring
and cultivating are compared with those of loamy and clayey soils.

A Warning". Although farmyard manure possesses the great virtues
mentioned it must be used with care and intelligence. In some places,
where large and cheap supplies are available, the soil is saturated with
manure. The greater the quantity of manure incorporated with a soil
the greater the necessity for plenty of fresh air to bring about decom-
position, and ultimately humus. Now, if a soil has not been deeply dug
or trenched, and it happens to be of a heavy nature, it is possible that
the rains will not pass away readily. Then the manure begins to get
sour, fresh air with its oxygen is driven out, carbonic acid gas develops too
freely, and the beneficial bacteria are suffocated or annihilated by their
enemies which come into being owing to the lack of fresh air. To avoid
these troubles the soil should be well and deeply dug, and whenever extra
large quantities of manure are used the soil should afterwards be dressed
with lime or chalk, basic slag, or nitrolim, to keep it in a sweet
condition.

Green Manuring". This consists in growing a crop of some quick-
growing plant, which when near maturity is to be ploughed in or dug
into the soil, with the object of enriching it in humus or organic material
and nitrogen. Sometimes the crop is fed to cattle, and the manure from
the sheds is afterwards returned to the land. As one of the chief objects
of green manuring is to supply nitrates to the soil, such leguminous
plants as the Red, White, and Crimson Clovers, Peas, Vetches, Beans,
Lupins, &c., are favoured for the purpose, because the bacterial nodules
on their roots possess the power of fixing the free nitrogen from the air
(see p. 127). Such non-leguminous crops as Mustard, Rape, Buckwheat,
Borage, &c., are also grown as green manures because of their bulkiness
and rapidity of growth, and the large amount of humus, &c., they return
to the soil.

Whichever of these crops is grown the effect upon the soil is beneficial.
The roots penetrate the soil and divide it into finer particles. Mineral and
metallic foods are dissolved by the secretions from the roots, and being
rendered soluble in water can be absorbed into the system of the crop.
The soil becomes drier by the absorption and transpiration of moisture
if it is inclined to be too wet; and eventually when the crop is ploughed
in, or dug in completely, large quantities of humus become incorporated
with the soil. As the green stems and leaves and roots decay in the
dark a certain amount of heat is generated, carbonic acid gas is liber-
ated and proceeds to dissolve the inorganic materials in the soil, and
all the wonderful chemical changes due to the presence of humus take
place in proper order to make the soil richer than it was before.

Manures and Manuring

149

Many experiments have been carried out to prove the value of "green
manuring", and an interesting paper on the subject will be found in the
Journal of the Board of Agriculture, for June, 1897. The following figures
show how a soil may be enriched in nitrogen and other foods when a
green crop is incorporated with it:

Name of Crop.

Dry Substance
per Acre.

Fixed Nitrogen
per Acre.

Equal to
Nitrate of Soda.

Ib.

Lathyrus Clymenum . . .

5100

154

1000

Peas

7140

198

1267

Mixed leguminous plants

5998

165

1028

Lupins, white ...

6273

162

1039

blue

7020

171

1081

yellow

5090

130

847

From this experiment it would appear that Peas are the best crop to
use as a green manure. Not only is there a larger supply of dry substance
(over 3 tons per acre), but nearly 200 Ib. of nitrogen is fixed in the soil.
This is equal to over ton of nitrate of soda. Reckoning the value of
nitrate of soda at 10 per ton, the pea crop yielded up nitrogen to the
value of 5 per acre, in addition to the other foods supplied by the decay-
ing stems, leaves, and roots. The Yellow Lupins supplied over 5000 Ib.
of dry matter, and 130 Ib. of nitrogen to the acre, and is thus the poorest
of the leguminous fertilizers. Notwithstanding this fact it appears that
any of the green manures mentioned are capable of supplying more
nitrogen to the soil than is needed by most crops. Hops require about
200 Ib. of nitrogen per acre, and this quantity can be supplied in advance
by a crop of Peas. But Potatoes require from 50 Ib. to 120 Ib. of nitrogen
per acre, and leguminous crops can supply far larger quantities as shown.
The value of leguminous crops as manure was well known to the ancients,
and Virgil in his "Georgics" refers to them thus:

" At least where Vetches, Pulse, and Tares have stood,
And stalks of Lupines grew (a stubborn wood),
The ensuing season, in return, may bear
The bearded product of the golden year ".

Leaves as a " Green Crop ". The subject of
carried further than is generally supposed. There
whether fruits, flowers, or vegetables, that cannot
green manure. Even the weeds and herbage from
can be turned to good account as soil fertilizers,
only pay as a green manure but will also remove
places for many garden pests.

Taking cultivated crops, the leaves of many of
in autumn and when decayed form an excellent

green manuring may be
is scarcely a crop grown,
be utilized in part as a
the banks and waysides
and if utilized will not
one of the chief nesting

them drop to the ground
vegetable mould or leaf

150 Commercial Gardening

soil, the value of which is well known to all gardeners who cultivate pot
plants of any description. But the leaves and stems of such crops as
Potatoes, Carrots, Parsnips, Turnips, Beet, Mangel, Peas, Beans, Jerusalem
Artichokes, and the stems of many Cabbage crops, &c., are often available
as vegetable refuse, and may be utilized to improve the soil. The quantities
of leaves and stems vary according to the different crops, but the following
is a fairly approximate estimate per acre of some. Beet, 15 tons; Cabbage
crops, 7 tons; Jerusalem Artichokes, 13 tons; Turnips, 12 tons; Potatoes,
6 tons; Parsnips, 10 tons; Apples, Pears, and Plums, 4 tons.

Vegetable refuse of this description, as well as the clippings of hedges,
the dead stems and leaves from flower borders, &c., makes an excellent
fertilizing material for the soil. It may be utilized in a green or raw
state whenever the ground is being trenched, or in a decomposed state as
a compost when digging or ploughing. Many market gardeners and
farmers are well aware of the value of this material and take advantage
of it.

The only danger to be apprehended is in the case of Potato stalks and
clubrooted Cabbages. These contain terrible fungoid diseases, and it is
generally safer to have them burned than dug into the soil. Although
burning will drive off all the organic foods, the ashes left behind will con-
tain valuable fertilizing salts that may be dug in afterwards.

Roots as a Manure. Besides the overground stems and leaves of
crops, one must not forget the roots. Although many crops are said to
be cleared off the ground, the fact remains that a very large quantity
of fibrous roots of all crops are left behind in the soil; and the more
rudely the plants are taken up the larger the quantity of roots left
behind. This may be easily seen by pulling up a cabbage or a lettuce
by hand, and comparing the roots attached with those on similar plants
that have been carefully lifted with a fork. As the roots decay they
become humus and have all the fertilizing value of that organic material.
It has been estimated that in an acre of grass land at Rothamsted there
were over 4J tons (10,400 Ib.) of roots in the soil at 9 in. deep; and these
roots contained 78 Ib. of nitrogen to the acre.

It will thus be seen that, even if stable manure and artificial fertilizers
are excluded altogether, very large supplies of plant foods may still be
secured from the waste leaves, stems, and roots of the crops themselves.
It is therefore wise to take a leaf out of the book of the Continental, as
well as the Chinese and Japanese cultivators, and avoid wasting the
vegetable remains of any crop. If they are burned or thrown away, it
is equivalent to wasting valuable supplies of nitrates, potash, phosphoric
acid, lime, sulphur, soda, magnesia, and other plant foods, for which high
prices will have to be paid.

Guano. This is a valuable manure, consisting chiefly of the dried
excrements and waste of sea birds, which have accumulated for centuries
on the coasts and rainless districts of Chili and Peru. The famous
traveller Humboldt first brought samples of guano to Europe in 1804,

Manures and Manuring 151

but it was not till 1840 that the first cargo reached Britain. Five years
later nearly 300,000 tons were imported, and enormous quantities arrived
annually, until soon after 1870 the supplies began to get exhausted. The
Peruvian guanos are now completely worked out, and supplies have to
be obtained from other sources, such as the coasts of Bolivia, Colombia,
and Patagonia, Australia, South-west Africa, and certain islands in the
Pacific. The importations now are small in comparison with those of
earlier times. In 1901 only 13,000 tons were imported, and in 1907,
31,278 tons of all kinds of guano. The original Peruvian guanos were
very rich in plant foods, containing 14 to 16 per cent of nitrogen, 12 to
14 per cent of phosphoric acid, and 2 to 3 per cent of potash. They were
thus "complete" fertilizers. Modern guanos, however, seldom contain
more than 10 per cent of nitrogen, and may contain as little as 2 per
cent. Purchasers should always insist on obtaining a warranty when
buying guano, and samples should be analysed from time to time to test
the manurial value.

"Guanos are commonly divided into nitrogenous and phosphatic. Ni-
trogenous guanos are those which contain a considerable percentage of
nitrogen, generally over 4 per cent. They may also contain a large
percentage of phosphate. A recent sample, for instance, contained 6 '3 per
cent of nitrogen and 32 per cent of phosphate. Phosphatic guanos, on
the other hand, contain little nitrogen, generally from 1 to 3 per cent,
but they should contain a considerable percentage of phosphate. Usually
the phosphate is from 30 to 50 per cent, but samples containing as much
as 70 per cent are sometimes on the market" (The Standard Cyclopedia
of Modern Agriculture).

Fish Guano. Soon after 1870, when the supply of Peruvian guano
began to fail, it was thought that fish refuse might be utilized for the
production of guano especially as the latter manure came from birds that
fed largely on fish. Although the methods of manufacture were at first
very crude, and a good deal of oil was incorporated with the manure, great
improvements have been effected in late years. Fish guano is chiefly valu-
able as a manure for its nitrogen and phosphates, the quantities of which
vary according to the kind of fish. The supply of nitrogen will be larger
in fish having plenty of flesh and little bone, while the phosphates will be
greater in fish having much bone and little flesh. There is also a small
quantity of potash and lime. The nitrogenous value varies from 7 to 16
per cent, according to the kind of fish and the process of manufacture. The
phosphates vary from 3 to 20 per cent. What is known as " white fish "
guano is made from the heads, bones, and waste of haddocks, cod, ling,
and other non-oily fish, and is superior to the guano obtained from
herrings.

Seaweed. Various kinds of seaweed have long been used as manure
when obtainable in sufficient quantities round the coasts. The commonest
kinds are species of Laminaria and Fucus, the latter genus supplying two
well-known species met with almost everywhere, namely, F. vesiculosus

152 Commercial Gardening

and F. nodosus. Seaweed is variously known as wrack, bladderwrack,
black wrack, and black tang in different parts. During the summer
months, after the tide has receded, the seaweed is gathered and laid out to
dry along the shores. It is turned over a few times, as if it were hay, and
when sufficiently dry is stacked in conical heaps for autumn and winter
use. During the winter seaweed cannot be dried and stacked in this way,
as it melts away into an oily liquid. It is therefore applied direct to
the soil when collected at this season. The value of seaweed is due to the
amount of potash it contains from 30 to 40 Ib. in a ton. It also contains
about 10 Ib. of nitrogen and 10 Ib. of phosphoric acid, as well as 11 to 18
Ib. of lime to the ton. It is therefore a " complete " manure, but is not so
valuable as farmyard manure. For Potatoes, Peas, and Beans it is excel-
lent in light soils, and a good dressing would be from 12 to 20 tons per
acre.

Soot. This is principally composed of carbon, and is not only valuable
as a manure, but also as a preventive against attacks of slugs, snails, cater-
pillars, &c. One ton of soot contains about 90 Ib. nitrogen, 25 Ib. phosphates,
25 Ib. potash, and 200 Ib. carbonate of lime. It is therefore an excellent
all-round manure, and after it has been exposed to the air for six or eight
weeks may be safely used for almost any vegetable or flower crop in the
open air. From 30 to 50 bus. per acre is a fair dressing. Soot is highly
valued as the basis of a liquid manure by gardeners who grow large num-
bers of plants in pots. About 1 pk. to 30 gal. of water will yield a useful
liquid manure. It is better to put the soot into a bag and sink it in a tub
of water, as the loose soot does not mix freely with the water. Owing to
its chemical composition it is a much better and safer liquid manure than
sulphate of ammonia or nitrate of soda.

Blood Manures. Blood may be regarded as a complete fertilizer, as it
contains not only nitrogen (from 2J to 5 per cent in a fresh state, and from
6 to 14 per cent in a dried state) but is also rich in all other plant foods, as
may be seen by the following analysis of the ash:

Per cent.

Sodium phosphate ... ... ... ... 16'77

Calcium and magnesium phosphates ... ... 4-19

Oxide and phosphate of iron ... ... ... 8 '28

Sodium chloride (common salt) ... ... 59 '34

Potassium chloride ... ... ... ... 6'12

Calcium chloride ... ... ... ... 3 '85

Calcium sulphate (gypsum) ... ... ... 1*45

TOCHJQ

[t will be observed that common salt constitutes more than half the weight
of blood ash. When fresh blood can be obtained from slaughter houses it
is best mixed with large quantities of soil and then allowed to " mature " in
a heap until wanted for use. Dried blood is a more concentrated source
of nitrogen than fresh blood, as water has been eliminated. It is a good

Manures and Manuring 153

fertilizer for all well-worked soils, and may be regarded as specially
valuable for Potatoes, Cabbage crops, Vines, and fruit.

Night Soil and Poudrette. Human excreta are rich in fertilizing
substances, and their value as manures was more highly appreciated before
the general adoption of the water closet and sewage systems. Even to-day
the Chinese and Japanese gardeners, who achieve such marvellous results,
have the highest respect for night soil as a fertilizer. On the Continent
also it is valued as a manure; and under the pretty name of "poudrette"
it is found mixed with gypsum, ashes, earth, peat, sawdust, &c., to mask the
smell. Some market growers of flowers now use night soil for purposes of
liquid manure.

Closely associated with night soil is the " native guano " obtained from
the precipitated solids in sewage beds. It is mixed with various things,
such as alum, charcoal, &c., and is sold in a dried state. A ton of it con-
tains from 20 to 40 Ib. of nitrogen, 60 to 120 Ib. phosphate of lime, and
about 50 to 100 Ib. of alkalis of potash, soda, and magnesia. If too many
poisonous chemicals have not been used at the sewage works, native guano
is worth using as a topdressing at the rate of \ ton to the acre.

Rape Cake and Rape Dust. Rape cake is largely used by some agri-
culturists not only as a manure but also as a wireworm catcher. Rape cake
contains a certain amount of oil, but of late years this has been almost
entirely extracted, and the cake is made up into the form of meal. As a
manure it is chiefly valuable for its nitrogen, 1 ton containing about 100 Ib.
There are also smaller quantities of phosphates, potash, and lime present,
thus making rape cake and rape dust a complete if not very rich manure.
It is useful as a topdressing at the rate of \ ton to the acre; or it may
be dug or hoed in.

Malt Dust OP Kiln Dust. This is obtained from malt houses and
consists of the dried rootlets and shoots that have been screened from the
kilned malt. Malt dust is a very useful organic manure, and may be
regarded as a complete fertilizer. It is excellent as a topdressing at the
rate of 30 or 40 bus. to the acre, particularly during hot, dry summers.
The ash is rich in phosphates (25 per cent) and in potash (30 per cent), but
contains little lime (3 per cent). The market price of malt dust varies from
35s. to 60s. per ton.

Wool and Shoddy. Pieces of woollen cloth and shredded portions
called shoddy are valuable organic manures, being chiefly valued for their
nitrogen. This varies from 2 to 13 per cent, according to the purity of the
wool from which the shoddy is obtained. As it liberates its nitrogen
slowly, shoddy is regarded as a good manure for Hops, Vines, Roses, &c.
Besides wool and shoddy all waste cloth refuse might be converted into
a manure. It should be placed in layers and covered with soil, and when
thoroughly decayed may be spread over the soil as a topdressing. The
soil prevents the escape of any ammonia gas generated in the process of
decomposition.

Hair, Feathers, Skin, Leather Waste, Greaves may be associated

154 Commercial Gardening

with wool waste and shoddy as manures. They all contain appreciable
quantities of nitrogen, and when thoroughly decomposed and matured by
mixing with layers of soil, they constitute valuable organic additions to
the soil.

4. NITROGENOUS MANURES

Nitrogenous manures are chiefly valuable because they give a luxuri-
ance and brilliancy of colour to the foliage of plants, thus enabling them
under healthy conditions to absorb sufficient supplies of carbonic acid gas
from the atmosphere during the daytime. The practical gardener may
therefore by a mere glance at his plants be able to say whether his plants
are lacking in nitrogenous food or not. When the leaves are luscious and
deep green, and the shoots are gross and sappy, it is a sure sign that there
is an abundance of nitrates in the soil. Such rank growth can only be
produced by their presence. It would therefore be a mistake to add nitro-
genous manures to such a soil. To check the rankness of growth, however,
it would be wise to add phosphates, potash, or lime, and thus induce the
formation of flowers and fruits instead of wood.

Amongst natural substances which supply nitrates to the soil are farm-
yard and stable manure, leaves, the dung of such animals as the horse, cow,
pig, sheep, poultry, rabbit, and all refuse from them, such as wool, shoddy,
horn, hair, feathers, skin, leather, meat meal, dried blood. To these may be
added fish manure, oilcake manure, night soil, and poudrette.

Indeed these materials not only supply nitrogen, but also certain quan-
tities of potash, phosphoric acid, and lime, as well as other foods. They
may therefore be looked upon as complete fertilizers.

Amongst artificial manures supplying nitrogen are nitrate of soda,
sulphate of ammonia, nitrate of potash, nitrate of lime, nitrogen, and
guano.

When the natural manures, which are all of animal origin, are incor-
porated with the soil, and are in a thoroughly decayed condition, they
possess all the advantages of humus, and are safe and reliable. They keep
the temperature equable, retain sufficient moisture, bring bacteria into
being, dissolve mineral matters, and gradually yield up their foods to
the roots of the plants.

Nitrate Of Lime. This is a new nitrogenous fertilizer produced from
the oxygen and nitrogen of the atmosphere by an electrical process. The
commercial product is a hard crystalline substance which contains about
13 per cent of nitrogen. It is very soluble in water and has the disad-
vantage of being very deliquescent, owing to its affinity for moisture in the
air. It must therefore be kept in a very dry place, and it is best used as
a topdressing to growing crops in the same way as nitrate of soda.

Nitrate of Soda OP Chili Saltpetre. This is one of the best-known
artificials, and enormous quantities are sold every year. It is found in
layers of varying thickness in parts of Chili, whence 1,738,540 tons wen;

Manures and Manuring 155

exported in 1908. The Continent absorbed 1,272,000 tons, the United
States 308,000 tons, and the United Kingdom 105,000 tons, about one-half
the supply being used for agricultural and horticultural purposes.

Commercial nitrate of soda contains from 95 to 96 per cent of actual
nitrate of soda, the remaining 4 to 5 per cent consisting of moisture, salt,
soda, magnesium sulphate, &c. The best samples with 95-per-cent purity
contain about 15'6 per cent of nitrogen, this being equivalent to 19 per
cent of ammonia.

Nitrate of soda is a very quick-acting manure that is, it yields up its
nitrogen soon after application and especially after a shower of rain. It
should therefore only be applied to soil which is carrying a crop in full
growth, and which shows by the colour of its foliage that a dressing would
be beneficial. As growth is most rapid in spring and summer, these are the
best seasons for applying nitrate of soda. As an autumn or winter dressing
it would be practically wasted. The quantity given will vary from 1 cwt.
to 2 cwt. per acre, or, roughly, f Ib. to 1| Ib. to every square rod or pole
of ground. As a stimulant in conjunction with organic manures already in
the soil, nitrate of soda is excellent for Cabbage crops, including Turnips
and Kohl Rabi, as well as for Beet, Spinach, &c. It is only rarely necessary
to apply it to leguminous crops like Peas and Beans, as these are capable of
securing their own supplies of nitrogen from the atmosphere. Perhaps the
best way to use nitrate of soda is as a topdressing, afterwards working it
into the soil with the hoe; or for pot plants by dissolving about 1 oz. in
1 gal. of water. If used dry, a mere pinch as much as will cover a three-
penny piece is quite sufficient for plants in 5-in. pots.

Nitrate of soda may be used with basic slag, but should never be mixed
with sulphate of ammonia or kainit; and it can be only safely mixed in
small quantities with superphosphate of lime, owing to the danger of
decomposition.

Nitrate of Potash. This is popularly known as "saltpetre "or "nitre".
Owing to its high price it is very little used by farmers and gardeners. It
is not only rich in nitrogen, but also in potash, and should therefore be
regarded more as a potassic manure. When of 85-per-cent purity it con-
tains 14 per cent of nitrogen and 40 per cent of potash.

Sulphate of Ammonia. This resembles nitrate of soda somewhat in
appearance but is rather coarser in the crystals. It is a compound
of ammonia and sulphuric acid, and is obtained from the ammonia liquor
of gasworks, ironworks, &c. In a pure state it contains 25'8 per cent of
ammonia, equal to 21*2 per cent of nitrogen. A pinch of unadulterated
sulphate of ammonia will vaporize completely on a red-hot surface. The
commercial product, however, of about 95-per-cent purity contains 24'5 per
cent of ammonia, equal to 20'2 per cent of nitrogen. It may be used in
the same way as nitrate of soda, but is more lasting in its effects. It should
not be mixed with nitrate of soda, basic slag, or with lime or chalk, as these
would liberate the ammonia and cause it to be lost.

The production of sulphate of ammonia has increased from 42,000 tons

156 Commercial Gardening

in 1872 to 289,000 tons in 1906, and more than one-half the quantity is
obtained from gasworks.

Sulphate of ammonia is neither an acid nor an alkaline manure; it is
a neutral substance, and when added to the soil causes a loss of calcareous
or chalky food (see p. 161.)

Nitrolim or Calcium Cyanamide. This manure has recently come
into prominence as a nitrogenous fertilizer. It is obtained from calcium
carbide, so much used for acetylene gas. When this is heated to 1000 C.
the nitrogen from the atmosphere combines with it and forms about 60
per cent of calcium cyanamide. This contains 20 per cent of nitrogen,
the remainder being 24 per cent quicklime, 10 per cent carbon, and 15 per
cent of various mineral oxides. In appearance nitrolim resembles basic
slag, being a dark -grey finely powdered substance. In action it is some-
what similar to sulphate of ammonia, and is much slower in its action than
nitrate of soda.

5. PHOSPHATIC MANURES

Phosphatic manures are derived from various sources, and are valuable
because they induce the earlier production of flowers and fruits. They
are mainly useful for the supply of phosphoric acid, which is an ingredient
of every part of a plant, and exists in considerable quantities in some, such
as the Cauliflower, the Radish, Peas, and Beans. There are fair supplies of
phosphoric acid in the soil, as much as 2750 Ib. to the acre being recorded
at Rothamsted in a field that had not been manured for fifty years. As
already stated, from 20 to 125 Ib. of phosphoric acid per acre is a sufficient
supply for most crops. These quantities may be liberated by deep cultiva-
tion and the addition of stable manure, and by the judicious application
of some of the following "artificials", chiefly remarkable for their phos-
phates.

Bones. The use of bones as a manure dates from the earliest times,
and has become more extensive than ever. Between 45,000 and 60,000 tons
of bones in various forms have been imported annually in recent years from
the East Indies, the Argentine, Brazil, Morocco, Egypt, and the Continent.
In addition to this it is computed that about 60,000 tons of bones are also
available annually in the United Kingdom. This would bring the manurial
consumption of bones up to about 100,000 tons per annum.

In a natural state bones are crushed into various sizes, and in the form
of bone meal are very popular with gardeners. A ton of bone ash contains
from 800 to 900 Ib. of phosphates; while 1 ton of dissolved bones, and
1 ton of steamed bones contains from 300 to 600 Ib. of phosphates. Bone
flour is also a valuable phosphatic manure, containing over 300 Ib. of phos-
phates in 1 ton, and also yielding up a small quantity of nitrogen. Dis-
solved bones also yield up even a larger supply of nitrogen.

Superphosphate. This is one of the most popular phosphatic manures.

Manures and Manuring 157

It is obtained by treating substances containing tricalcium phosphate with
sulphuric acid. At first superphosphate was made from bone ash and bone
black, but the great bulk is now obtained from natural minerals (phos-
phorites, coprolites, apatites). Many millions of tons are produced annu-
ally, about 800,000 tons being manufactured in the United Kingdom.
Commercial samples contain from 25 to 40 per cent of soluble phos-
phates, but there is great variation. When buying, the soluble phosphates
only should be taken into account, the insoluble phosphates not being
highly valued.

When superphosphate is applied to the soil, the phosphates, being
soluble in water, are well distributed amongst the soil particles by a
shower of rain. Then a change takes place. The soluble phosphate
reverts into an insoluble state owing to the carbonate of lime (or chalk)
and the compounds of iron and alumina present in the soil. This change
prevents the phosphates from being washed out of the soil too readily.

Superphosphate is an acid manure, and therefore tends to use up the
available lime in the soil (see p. 161).

Basic Slag". This is a by-product in the manufacture of Bessemer
steel, and is also known as "basic cinder" and "Thomas's phosphate".
It is a fine dark-grey powder, 80 per cent of the particles of which should
pass through a sieve having 10,000 holes to the square inch. It is only
since 1885 that basic slag has been used as a manure, having previously
been discarded as a waste product. The estimated production for the
whole world in 1885 was 150,000 tons, and in 1906 as much as 2,383,000
tons. Of this quantity Germany produces 1,510,000 more than one-half ;
the United Kingdom being second with 300,000 tons.

Basic slag is an alkaline manure, and usually contains from 30 to
40 per cent of phosphate of lime, which is equivalent to 9 to 18 per cent
of phosphoric acid. The phosphate in basic slag is in combination with
lime, and in good samples the greater part of the phosphate can be dis-
solved in a dilute solution of citric acid. As the value of basic slag

depends largely upon its solubility in citric acid, purchasers should obtain
a guarantee as to its citric solubility, as there are inferior brands of basic
slag in existence. If 90 per cent or more is soluble, the sample is a
good one.

Basic slag is a valuable manure for all soils except those of a chalky
or limestone nature. It is particularly valuable where large quantities of
stable manure have been applied, and where there is a tendency to acidity.
For fruits, flowers, and vegetables of all kinds basic slag may be used
at the rate of 2 cwt. to 4 cwt. per acre. There is a general impression
that it should be used only during the winter months. In practice it
will be found useful if applied to the soil about three months before the
crops are likely to require it. It yields up its phosphates slowly, but in
the meantime the lime is acting in conjunction with the humus in the
soil and excites bacterial activity. When finally potting Chrysanthemums,
Zonal Pelargoniums, Begonias, and a host of other plants, a sprinkling of

158 Commercial Gardening

basic slag over the compost heap will produce excellent results in the way
of early bloom, &c.

Wood Ashes, &C. Besides bones, superphosphate, and basic slag, other
manures are also valuable for the amount of phosphates they contain.
Wood ashes, i.e. the burnt refuse from weeds and plants of all sorts, con-
tain from 100 to 145 Ib. of phosphates in every ton, and even a larger
supply of potash 135 to 224 Ib. in every ton.

Guanos both Peruvian and fish also contain large quantities of phos-
phates, Peruvian guano having from 350 to 400 Ib. in every ton, and fish
guano from 200 to 300 Ib. Farmyard and stable manure, seaweed, sewage
sludge, soot, night soil, pigeon, poultry, and all animal excreta contain
supplies of phosphates as well as nitrates and potash.

Limphos. This name has been given to a new fertilizer, said to contain
40 per cent of phosphates and 35 per cent of lime. It is probably a com-
mercial name for a form of superphosphate, and is no doubt similar in
action.

6. POTASH MANURES

It must be a very poor soil indeed which does not contain large supplies
of potash. This is locked up with other elements, but fair quantities may
be liberated annually by cultivation and the application of organic manures.
A fertile soil has been computed to contain about 30,000 Ib. of potash to
the acre at 9 in. deep, while a soil at Rothamsted which had not been
manured for fifty years contained 6750 Ib. of potash to the acre at 9 in.
deep. The quantity of available potash needed for certain crops varies
from 36 to 500 Ib. per acre, as may be seen by reference to the figures
on p. 144.

Before referring to special artificial potash manures it may be remarked
that all organic manures, such as stable manure, the dung of all animals
and birds, soot, seaweed, and wood ashes, contain supplies of potash,
which are liberated when incorporated with the soil.

Amongst the special potash manures are the following:

Kainit. This is one of the most popular potash manures at present
in use. It is a crude natural salt obtained from Germany, and varies in
colour from creamy white to pale pink. Pure samples contain potassium
equal to nearly 19 per cent of potash. The usual commercial article only
contains about 12'4 per cent of potash. In bulk, commercial kainit con-
tains about 35 per cent of common salt, about 30 per cent of magnesium
salts (chiefly Epsom salts), and about 12*5 per cent of water of crystalliza-
tion. The remainder 22*5 per cent is almost entirely potassium salts.
It will thus be seen that less than one-fourth the bulk consists of the
important fertilizer potash.

As a manure, kainit has the disadvantage of having such a large per-
centage (35) of common salt, but with such crops as Mangels and Asparagus
this is not a drawback, as those crops benefit by the addition of salt to the

Manures and Manuring 159

soil. It would, however, be unwise to apply kainit to a soil carrying grow-
ing crops, as the salt and other impurities are likely to injure the tender
rootlets.

The best time to apply kainit is a few weeks before the crop is to be
sown or planted. The salt in it, being readily soluble, will be washed down
into the soil out of reach of the roots, and the potash will be left behind
evenly distributed amongst the soil particles. From 2 to 4 cwt. per acre
is a fair dressing for kainit.

Muriate of Potash. This is another name for a more or less impure
chloride of potassium. It is manufactured from carnallite, which is found
in enormous quantities in the German potash deposits. It contains from
70 to 98 per cent of pure potassium chloride, and its chief impurity is
common salt, which may vary from a mere trace to 20 per cent. Small
quantities of magnesium chloride and magnesium sulphate are also present.
The standard commercial muriate of potash usually contains 80 per cent
of pure potassium chloride, which is equivalent to 50'5 per cent of potash.
One ton of "muriate" thus contains as much potash as 4 tons of kainit.
In practice it may be used in the same way as kainit, but only one-fourth
of the quantity is needed about 56 to 112 Ib. per acre.

Sulphate of Potash. This is a whitish crystalline salt manufactured
from natural deposits in the German potash mines. As a manure, the best
samples contain 98 per cent of sulphate of potash, equal to over 52 per cent
of pure potash. Inferior samples contain about 90 per cent of sulphate
of potash, equal to 48 per cent of pure potash. The double sulphate of
potash magnesia, which contains a good deal of magnesium sulphate, is
often called sulphate of potash, but it is inferior in potassic value. It
contains about 50 per cent of sulphate of potash, equal to 27 per cent of
pure potash.

Sulphate of potash has gained a great name as a potato manure. It
is considered to produce tubers of better quality, but this would depend
largely upon the character of the soil.

7. CALCAREOUS MANURES

These are of a most important nature, and consist of lime in some
form, such as quicklime, slaked lime, chalk, marl, gas lime, and lime
shells. Lime is not only an essential plant food (see p. 108), but it plays
an important part in the generation and activity of bacteria in the soil,
and must be present to ensure fertility. Some soils are naturally of a
calcareous nature, while others may be deficient. In a fertile soil it has
been estimated that there are about 120,000 Ib. of lime to the acre, but
the quantity is very much less in others. In the Broadbalk Field at
Rothamsted, which had not been manured for fifty years, as much as
62,250 Ib. of lime is given for an acre of ground.

Since the advent of so many chemical manures the ancient practice

160 Commercial Gardening

of " liming " the soil has largely gone out of fashion. Market gardeners
and farmers, however, appear to be again waking up to the importance
of lime, not only as a cheap and excellent manure, but also as a powerful
check to " clubroot " in Cabbage crops, to " eelworm " in Cucumbers and
Tomatoes and other crops, and by keeping many other pests at bay.
The old saying that

" Lime and lime without manure
Makes both farm and farmer poor ",

is perfectly true, and it illustrates the wisdom of our forefathers. Owing
to chemical actions set up in the soil by the presence of lime, organic
matter like stable manure is rapidly converted into such a state that its
nitrates, potash, phosphoric acid, &c., are soon liberated and absorbed.
Consequently, unless manure is added regularly to the soil, it would soon
be brought into an impoverished state by the continual application of
lime alone.

In a state of nature lime does not occur in a free state. It is usually
combined with carbonic acid, and in many parts is found in abundance as
carbonate of lime the commonest forms of which are limestone and chalk.
Pure carbonate of lime is composed of 53'6 per cent of lime and 437 per
cent of carbonic acid. When burnt in a kiln the carbonic acid gas is
driven off into the atmosphere, and the residue quicklime is formed.
This quicklime absorbs water greedily, and in coming in contact with it
becomes " slaked ". This is then called hydrate of lime, or, more properly,
slaked lime. If left exposed to the air the slaked lime gradually loses
its water, and absorbs carbonic acid gas instead. It thus becomes carbonate
of lime once more.

In wet, heavy, clayey soils the application of "quicklime" or caustic
lime to the surface is of the utmost benefit after the soil has been turned
up with the spade, fork, or plough. The quicklime readily absorbs the
surrounding moisture, generates great heat, and brings the soil into a
drier and better condition for working. For heavy land there is nothing
better than a good dressing of quicklime to bring it into a state of cultiva-
tion. From 30 to 200 bus. per acre is applied according to circumstances.

Chalk, or carbonate of lime, is also an excellent dressing for most farms
and gardens that receive liberal dressings of manure. The latter is apt
to generate acidity if the soil has not been deeply dug or trenched, and
this acidity in turn is apt to produce clubbing of Cabbage crops, eelworm,
and other plant diseases, owing to the lack of oxygen in the soil. Lime in
any form helps to check this state of affairs.

Marl, which is a mixture of clay and chalk in varying proportions,
is a useful adjunct to light or gravelly soils, because it makes the particles
more tenacious, and this enables the soil to hold manures better. There
are several kinds of marl, such as clay marl, sandy marl, chalk marl,
slaty or stony marl, shell marl, and peaty marl all containing a certain
quantity of calcareous matter.

Manures and Manuring 161

Gas Lime obtained from the gasworks is often used for garden pur-
poses. In a fresh state it contains many compounds fatal or poisonous
to plant life; but in this state it is a valuable dressing for soil infested
with clubroot (Plasmodiophora). It must not, however, be applied in
a fresh state to land already carrying a crop. After exposure to the
weather for about three months gas lime loses its poisonous properties
and then becomes a very useful manure. In composition it may contain
as much as 40 per cent of chalk (calcium carbonate) and 15 per cent of
slaked lime, but the amount of these varies considerably. About 5 tons
to the acre is a fair dressing.

Other lime manures are shells of various descriptions when ground and
obtainable in sufficient quantity. They are valuable for their carbonate
of lime and a certain amount of organic matter.

Since basic slag (see p. 157) has become prominent it is often used
instead of lime, and an excellent substitute it is, as it contains large
quantities of lime in a mild and useful form.

It has been found by experiment at Rothamsted that the application
of sulphate of ammonia to the soil causes a loss of carbonate of lime
(chalk), and growers would do well to bear this fact in mind. About
800 Ib. of lime per annum is naturally dissipated from the top 9 in. of
the soil by the action of the weather and cultivation, but the application
of 400 Ib. of ammonium salts raised the loss to 1045 Ib. The loss of lime
was still further increased to 1429 Ib. per acre by the application of 400 Ib.
of ammonium salts and superphosphate. It is therefore a simple matter
to rob a soil of lime simply by the careless or injudicious application of
sulphate of ammonia, superphosphate, and other manures.

Gypsum (Calcium Sulphate). This is well known as the source of
plaster of Paris. As a manure it is rarely used by itself, but it is largely
applied in the form of superphosphate. It is thought that the presence
of gypsum in the soil not only increases the solubility of the potash,
but also prevents the loss of nitrogen (in the form of ammonia) from
stable manure. Some authorities doubt this; but in any case gypsum
would scarcely pay for special application. It is favoured for light sandy
or gravelly soils, from 2 to 3 cwt. per acre being considered a reasonable
dressing.

8. MISCELLANEOUS MANURES

There are few substances beyond those already mentioned used as
manures, simply because there is very little to be obtained from them,
or because the foods they yield are generally present in superabundance
in the soil.

Magnesium Salts are sometimes applied as a potato manure, as mag-
nesium carbonate or magnesium sulphate (otherwise Epsom salts). Mag-
nesium occurs in the ash of all plants (see Tables at p. 109), and is returned

to the soil in farmyard and other natural manures.

VOL I. 11

[62 Commercial Gardening

Iron is also one of the essentials of plant life, but there are usually
large available supplies in the soil. Without a trace of iron it would
be impossible for the chlorophyll or green colouring matter of leaves to
develop, no matter how perfect other conditions might be. Recently
sulphate of iron at the rate of 8 oz. to a square rod has been used where
iron has been considered deficient owing to the yellowish colour of the
leaves. When sickly looking yellowish-leaved plants will not respond
to a complete fertilizer, or to a nitrogenous manure, the soil is then
probably deficient in available iron. Very often, however, the yellowish
appearance of leaves is due to sour and sodden soil, or to the absence
of lime.

Salt, or Chloride Of Sodium, is sometimes used as a special manure
for Asparagus and Sea Kale and other plants. In weak doses it seems
to be beneficial, and is said to liberate potash. From 1 to 2 Ib. to the
square rod may be used. Kainit, however, may be a safer manure to
use in quantity.

9. VALUATION OF MANURES

Chemical or artificial manures are valued chiefly by horticulturists and
agriculturists for the amounts of nitrogen, potash, or phosphates they
contain. The horticultural value, however, does not always correspond
with the commercial or market value, as the latter may be affected by
such questions as supply and demand, combinations, strikes, &c. The
cultivator naturally wishes to obtain the best value for his money.
Consequently, if he thinks he is paying too much for his nitrates, phos-
phates, or potash in a certain manure, he may cease to purchase it, and
buy another that will supply his wants at a cheaper rate.

Artificial manures are now valued at "unit" prices for nitrates, phos-
phates, and potash, but these unit prices are subject to fluctuations.

Nitrogenous manures are valued at a unit price fixed for the percentage
of nitrogen they contain; and nitrate of soda and sulphate of ammonia
are taken as the standard nitrogenous manures. Thus, if a ton of nitrate
of soda contains 15'5 units of nitrogen, and the price is 10 per ton, the

10
value of the nitrogen will be tr^, or about 12s. lOd per unit. If 1 ton of

sulphate of ammonia has 20 units of nitrogen, and is sold at 11 per ton,

the unit price is -gTp or 11s. It would therefore be cheaper to the grower

to buy sulphate of ammonia at 11 per ton than to buy nitrate of soda
at 10 per ton, as he would be obtaining better manurial value to the
extent of Is. lOd per unit. Of late years the price of nitrogen has varied
from 8s. 3d. to 12s. per unit.

For phosphatic manures superphosphate, basic slag, and ground Algerian
phosphates are taken as standards. In a superphosphate containing 32 per

Manures and Manuring 163

cent of soluble phosphate, costing 3 per ton, the cost per unit of phos-

3
phate would be = = Is. lO^d. Basic slag at 2, 10s. per ton, and contain-

2 10s
ing 40 per cent of phosphate, would represent a unit cost of ' = Is. 3d.

And ground Algerian phosphate at 2, 10s. per ton, but containing 60 per

cent of phosphate, would show a unit value of ~ ' = Wd.

Insoluble phosphates, although not of such immediate value, are never-
theless reckoned in the price of manures, and vary from Is. 4<d. to 2s. 9d.
per unit.

Potash manures are reckoned in the same way as nitrates and phos-
phates. Kainit, muriate of potash, and sulphate of potash may be taken
as standard potash manures. Thus, in kainit containing 12| per cent of

2 5s
potash, and costing 2, 5s. per ton, the phosphate would cost - ' ' = 3s. Id.

1*1
per unit nearly. Muriate of potash containing 50 per cent of potash at

9
9 per ton costs -^ = 3s. 7d per unit. And sulphate of potash with 50 per

9 10s
cent of potash at 9, 10s. per ton would cost j^. ' = 3s. 9^d. per unit.

With such manures as nitrate of soda, sulphate of ammonia, basic slag,
superphosphate, kainit, muriate of potash, and sulphate of potash, each
valuable for a certain ingredient, it is easy enough to calculate the cost
of nitrogen, phosphate, and potash per unit; but it is not so easy with
manures containing more than one valuable ingredient. Nor must natural

ra o

manures like stable or farmyard manure, dried blood, seaweed, &c., be
valued on the same basis, because they possess other properties apart
from their purely manurial value. If, however, the cultivator has a
knowledge of the unit system of valuing artificial manures he will find it
advantageous to buy sometimes one kind of nitrate, phosphate, or potash,
and sometimes another, and use them as required.

If we take a complete fertilizer, that is, one containing nitrates, phos-
phates, and potash, at the unit values quoted above, we get an example as

follows:

s. d.

Nitrogen, 7 units at 11s. = 3 17

Phosphate, soluble, 15 units at Is. IGd. = 176

insoluble, 7 units at Is. Qd. 10 6

Potash, 5 units at 3s. Id. 17 11

6 12 11
Add 25 per cent for mixing, storing, bags,

carriage, &c ... ... ... 1 13

Total cost per ton ......... 8 5 11

By obtaining a warranty with manures purchased, growers are thus able
to arrive at a very fair estimate as to the value of their manures, if they
price the percentage of nitrates, phosphates, and potash as given in the
above examples.

164

Commercial Gardening

TABLE SHOWING THE APPROXIMATE QUANTITY OF NITRATES, PHOSPHATES,
POTASH, AND LIME CONTAINED IN 1 TON OF MANURE

Name of Manure.

Nitrogen in
1 Ton.

Phosphates in
1 Ton.

Potash in
1 Ton.

Lime in
1 Ton.

Ib.

Basic slag

300-400

1120

Blood, dried

280

200

130

190

Bone, ash

800-900

1120

dissolved ...

300-350

flour

450-500

steamed ... ...

20-30

560-600

170

Chicken manure

Coprolites, Cambridge . . .

560

Coal ashes

15-20

Duck manure ...

Earth-closet manure

6-12

9-15

Farmyard manure

9-15

4-9

9-18

Geese manure ...

Guano, Peruvian

186

350-400

270

fish

160-200

200-300

110-180

Gypsum

500

Horn dust

260

Kainit ...

302

Leather waste ...

67-168

Marl

200-600

Meat meal

260

Malt dust (ash)

560

670

Muriate of potash

1120

Nitrate of lime ...

290

Nitrate of potash

313

1030

Nitrate of soda ...

358

Nitrolim (calcium cy-~l
anamide) ... /

450

530

Pigeon manure ...

40-70

Rape cake

100

Seaweed

30-40

11-18

Sewage sludge

15-40

60-120

50-100

Soot

200

Shoddy and wool waste

44-260

Sulphate of ammonia . . .

450

Sulphate of potash

900-1200

Superphosphate

270-290

Wood ashes

130-145

135-224

970

10. MIXING MANURES

The grower who wishes to save money by purchasing only the manures
he requires should also make himself acquainted with the different chemical
effects of one manure upon another; otherwise it may happen that what
is saved in one direction may be lost in another. If certain manures are
mixed with others, the fertilizing value may be either neutralized or lost

Manures and Manuring 165

altogether, owing to chemical changes taking place. The following hints
as to the manures that may or may not be mixed with each other may
be useful:

Farmyard or stable many/re should not be mixed with lime, because
the lime drives off the ammonia gas into the air and thus causes it to
be lost.

Nitrate of soda should not be mixed (except in small quantities) with
superphosphate, as the sulphuric acid in the latter sets free nitric acid
in the form of poisonous fumes, and the nitrogen is lost.

Sulphate of amTnonia should not be mixed with basic slag or nitrolim,
because the free lime in these manures would drive off the ammonia gas,
and, if in an enclosed place, is so overpowering as to be dangerous.

The following mixtures may be made with safety:

Sulphate of ammonia with superphosphate, dissolved bones, fish guano, and
potash salts.

Nitrate of soda with basic slag, nitrolim, meat meal, kainit.

Kainit or muriate of potash may be mixed with superphosphate, although
a little hydrochloric acid may be given off in fumes. [j. W.]

SECTION VI
Insect Pests

Within the past fifteen or twenty years commercial gardeners have
taken a much keener interest in the various diseases and pests that
prey upon their crops than their predecessors did. During that period
great changes have taken place in cultural conditions, and all crops are
now grown not only in larger quantities and on a more extensive scale,
but in many cases under what may be called an " express " or " intensive "
system. Every grower wishes to be first in the market, so as to secure
the highest price; and this very craze to be first with everything has
brought about insensibly and gradually changes in the constitution in
the various kinds of plants grown for market purposes. At one period
of the year they are forced or rushed into growth in great heat; at another
they are retarded or kept in check in a freezing atmosphere; while in
other cases, where neither forcing nor retarding is employed, some crops
are so drenched with chemical manures that it is not at all surprising
that some of them become so soft and tender in tissue as to fall an easy
prey to fungoid diseases and to insect attack.

No crop is now immune from attack, and this knowledge keeps the
commercial gardener constantly in a state of fear and apprehension. To
add to his troubles, some diseases, notably the American Gooseberry
Mildew, have been scheduled by the Board of Agriculture and Fisheries,
and a grower having any bushes affected with this disease is liable to
heavy penalties unless he reports the same. In some cases indeed, where
the orders of the Board of Agriculture have been treated lightly, some
market gardeners have been fined as much as 50.

Attacked by insect enemies and fungoid diseases on all sides, the
market grower has called in the aid of the entomologist on the one hand
and the chemist on the other, and has spent much money in experimenting
with various remedies that have been recommended either to check his
enemies or get rid of them altogether. The entomologist has assumed
a prominent position in describing the habits and marriage customs of
the various insects that are a plague to the gardener. And the mycologist
or fungologist tells of the wonders he has discovered through the micro-
scopic lens about the various fungi that make themselves unwelcomely
at home on the roots, stems, leaves, flowers, and fruits of various crops.

166

Insect Pests 167

With the aid of the mycologist, the entomologist, and the chemist,
telling him what to do under every conceivable method of attack, the
commercial gardener ought to be pretty well safeguarded by now, and
the war he has been carrying on for years on insect and fungoid
diseases ought to have decimated the ranks of his foes over and over
again. But, alas! it is not so. The various injurious insect pests and
fungi appear to be, if anything, in greater force than ever, and they
infest our crops with as great persistence as in former years.

Enormous sums of money are spent annually in emulsions, mixtures,
insecticides, fungicides, and poisonous nostrums of all sorts, in addition
to grease bands, smudging materials, &c.; and the trade in these remedies
seems to be getting larger instead of smaller. One would imagine that,
if the various anti-pest remedies on the market possessed any efficacy
at all, there should be very few insects left, and the trade in the remedies
would naturally contract instead of expand. One must, of course, recognize
that commercial growers are taking a keener interest in the diseases afflict-
ing their crops than they used to, and this would account in a measure
for the vast quantities of insecticides and fungicides that have been used
of late years. The hard fact, however, remains, that there seems to be
no diminution in either the numbers or attacks of the grower's persistent
foes; and this indicates the impotency rather than the destructive power
of the remedies.

While not wishing to minimize the value of the various insecticides
and fungicides on the market, the writer is of the opinion that they are
not always used to the best advantage and at times when they would
be most likely to perform the work expected from them. Owing to the
different natures and periods of destruction of the various insect pests
and diseases, it is essential that different remedies must be adopted at
the times when they are likely to prove effective.

Taking the insect pests first, they may be roughly divided into (1)
pests under glass, and (2) pests in the open air.

Greenhouse Pests. The insect pests that invade greenhouses are
perhaps as difficult to eradicate as any. There are so many chinks and
crevices in walls and floors for them to breed in, and they are so difficult to
reach that it is not to be wondered at that they escape the effects of washes,
vaporizers, and fumigators. While it is probably true that thousands of
insects in an active state must succumb to the fumes and washes, on the
other hand there must be thousands at the same time in a dormant stage
that are not affected in the slightest degree, being protected by a covering
that seems to be impervious to everything except fire. In due course
such pests come forth, after the danger is past, and play havoc with the
various crops, much to the surprise of the gardener, who thought he had
disposed of them.

The practical question is: How best are these enemies to be destroyed?
Certainly more drastic measures must be employed than those at present
in force. If the pests nest in the soil of a greenhouse, the gardener cannot

168 Commercial Gardening

expect any assistance from birds of the air to lessen their numbers, as
a bird in a plant house is literally a rara avis, and is too frightened and
flustered to search for the grubs or eggs of obnoxious insects. The grower
of crops under glass must therefore rely upon other remedies. Besides
using solutions made from nicotine, quassia chips, soft soap, arsenic, &c.,
on the plants themselves as preventives, the grower would be wise to
cleanse his houses thoroughly after they have been cleared of the crops.
The walls should be covered with hot limewash, and the woodwork should
be painted at least once a year, but more frequently if possible; and if
some paraffin and cement be churned up in the limewash, a thin covering
will be applied to the walls that will seal up effectually the eggs of any
pests that may be hidden in the crevices. In addition to this, sulphur
or brimstone should always be burnt in an empty house before a fresh
crop of plants is brought in. A strong sulphur vapour is not only fatal
to insect pests but also to fungoid diseases. By this means such stove
and greenhouse pests as scale, mealy-bug, red spider, thrips, slugs, snails,
wood-lice, ants, &c., may be reduced almost to vanishing point. The
keynote to immunity from pests in the greenhouse is cleanliness, not
only of the structures themselves, but also in the methods of cultivation.
A certain expense will be incurred, but it is better to spend it in this
way than in trying to secure freedom from attack by artificial means.

Fumigating. Besides keeping the walls and woodwork of glasshouses
clean with limewash, paint, &c., it is more or less essential at times to fill
the atmosphere with fumes that are deadly to pests that may be actually
feeding upon the crops, or are likely to become a nuisance in that way.
In former days the only method of cleansing a glass structure was by
applying tobacco smoke in some way or another. If the genuine tobacco
could not be afforded, rags and paper steeped in tobacco juice were utilized
as substitutes. The tobacco, rags, or paper were placed in flower pots,
or old saucepans, buckets, &c., with holes in them, on a few live coals in
the bottom. The fumigating mixture was damped, but not sodden, with
water, to prevent the flaring of the material, which would have been
injurious to the plants in that state. By means of bellows the fire was
kept alight, and as the moistened tobacco, paper, or rags were consumed,
dense volumes of smoke filled the atmosphere, and while it destroyed the
pests, if sufficiently powerful, also upset the operator in many instances.
Great improvements have taken place in fumigating greenhouses of late
years, and fumigating cones of various descriptions are now in use that
will fill the house with fumes after being lighted, and will not necessi-
tate the close attention of the gardener.

Vaporizing. Nicotine in some concentrated form has always formed
the staple fumigating material. It is now to be had concentrated in cake
or liquid form, and, although apparently expensive, is really very effective.
The cakes or liquid is placed in a shallow metal dish seated on a metal
stand. A small methylated-spirit lamp is placed beneath, and when lighted
dissolves the cakes or liquid into fumes that are diffused throughout the

Insect Pests

169

houses. These fumes are fatal to insect pests of all kinds, and if properly
applied are harmless to almost every plant. It is not wise, however, for
the gardeners to remain long after the lamps are lighted.

Cyaniding". Of recent years other methods of vaporizing have been
introduced, the best known perhaps being that known as the cyanide
process, in which hydrocyanic acid gas is diffused to kill mealy-bug, scale
insects, and others. This gas is generated by mixing potassium or sodium
cyanide, sulphuric acid, and water in various proportions. For Vines in
leaf, and other plants, it is recommended that not more than f oz. of
potassium cyanide, or | oz. of sodium cyanide, should be used to every

Fig. 91. Diagram showing Method of Fumigating with Hydrocyanic Gas

Line 11, for 100 cub. ft. read 1000 cub. ft.

P, Fan suspended from roof. F^ String
ing. c, Tray with cyanide, (f, Movable
owl containing sulphuric acid and water.
ig all three ingredients, and gas generating.

lOOGeub. ft. ot" space. To every ounce or cyanide use 1 oz. of sulphuric
acid and 4 oz. of water. The sulphuric acid and water are mixed slowly
together, and then the cyanide is dropped into the liquid, and the poisonous
gas, which is fatal to men and most animals, is rapidly generated and is
best diffused by using a fan as shown in the diagram (fig. 91). Great
care must therefore be exercised if these dangerous materials are used to
vaporize planthouses. Even if the fumes are inhaled for a few seconds
they may prove fatal. By using proper cyaniding apparatus, however,
there is practically no danger in the hands of competent operators. The
accompanying diagram will give one an excellent idea how a planthouse
should be vaporized with hydrocyanic acid gas. Sodium cyanide is con-
sidered better to use than potassium cyanide, as it dissolves more readily
and, taking weight for weight, liberates 30 per cent more gas.

Outdoor Pests. These are far more numerous than those afflicting
plants under glass. There is scarcely a fruit or vegetable, flower, tree,

170 Commercial Gardening

or shrub that is not subject to attack from one or more pests. Unfor-
tunately, few growers realize the mischief the various insects can do
until some crop is almost destroyed by an epidemic. When the danger
is discovered, then washes of all sorts and descriptions are tried, but
they are often too late in their application to be of any value.

If one must use washes and sprays it is wiser to use them as pre-
ventives rather than as cures, and before there is any sign of the crop
being attacked.

It is now well known that many leaf-eating and leaf-mining insects
can be foiled by the early application of some good insecticide. Thus,
aphides of all sorts, leaf-miners, caterpillars, and most soft-bodied pests
are prevented from doing mischief if the plants are syringed or sprayed
some time in advance of the usual period of attack. The various washes
and insecticides are mentioned in connection with the crops they attack.
As there is a right time and a wrong time for doing everything, the
intelligent grower will naturally make himself acquainted with the period
when certain insects are likely to commence their depredations, and spray
in advance. It would evidently be useless to spray after the insects have
eaten their fill and disappeared; applying insecticides under such con-
ditions would be equivalent to locking the stable door after the horse
had been stolen.

Seeking" the Cause. While the life-history and habits of the various
insects that prey upon plants may possess a charm for the entomologist,
the man who has to grow plants, flowers, fruits, and vegetables for a living
is by no means enamoured of them. No matter how interesting and
beautiful an insect may be in the various stages of its development, the
cultivator looks upon it as an unmitigated nuisance, that must be sup-
pressed at all costs. He regards nearly all insects as highway robbers,
who not only take money out of his pocket for insecticides, but who add
insult to injury by lowering or spoiling the market value of his produce,
and preventing the proper development of his plants.

Now, apart from insecticides there is another and more natural way
of combating these marauders. The cultivator should make himself
acquainted with the habits of the various pests, so that he may discover
their weakest and most vulnerable points. Having found these, then
is the time to attack them vigorously, when they are neither able to resist
nor escape; and although his efforts may not be crowned with complete
success, he will have the satisfaction of knowing that he has reduced his
tormentors to practically harmless proportions.

Life-history and Habits of Garden Pests. Farmers, gardeners, and
fruit-growers are indebted to the late Miss Ormerod and to the late John
Curtis, and more recently to Professor F. V. Theobald, of Wye College,
and Professor Walter Collinge, for the valuable information they have
placed on record with regard to the habits of the various insect pests.
Generally speaking, most of these have four different stages of existence:

1. The egg a dormant stage.

Insect Pests 171

2. The maggot, larva, grub or caterpillar usually the most destructive
stage.

3. The chrysalis or pupa the dormant and non-destructive stage.

4. The perfect insect, which in many cases may possibly help to fertilize
certain flowers at times.

The female insect is naturally more to be feared than the male, because
in many species she is capable of depositing numerous eggs, from which in
due course arise a devastating horde of hungry larvae. There are thus
two dormant stages in the life-history of an insect, namely, the egg stage
and the chrysalis stage, and two active stages, viz. the larva and perfect
insect. Some pests, however, notably the green fly or aphis, are not only
egg-bearing but also viviparous, i.e. at certain seasons they bring forth
young the females amongst which soon mature and bring forth families
with amazing rapidity.

In the active stage it is sometimes difficult to catch and even to see
some of the pests, as they assume many forms closely resembling in appear-
ance and colour the leaves and shoots upon which they are feeding. The
cultivator, however, with a keen eye will often detect the presence of
insect pests when others may be oblivious to their presence. While washes
and spra}'s applied at this stage will no doubt disable a large number of
pests, many must escape destruction, being thus saved to do further mis-
chief at some future time.

In the dormant stages of egg and chrysalis, however, the grower has
the pests at his mercy, and then is the time to make war upon them. By
destroying the eggs, future generations of caterpillars, &c., are suppressed,
and by destroying the chrysalides the future perfect insects are prevented
from giving rise to new families.

Methods of Prevention. But how are these eggs and chrysalides
to be destroyed? Entomologists tell us that the eggs of many insect pests
are protected by a covering impervious to most, if not all, of the insecticides
on the market. If that is so it would be waste of time and money to apply
these washes. In a cold state possibly many washes may be harmless to
the eggs of insect pebfcs, but if applied hot or warm, in the form of fine
spray, the liquid would probably soften the coat of the eggs and render
them pervious to the destructive properties of the insecticide. The embryo
larva would thus be destroyed. It may be stated that there is absolutely
no danger in applying boiling-hot solutions to plants in the open air, pro-
vided they are applied in the form of a fine misty spray, and with as much
force as possible. Even tender leaves of plants under glass will not be
injured by hot washes applied in this way, because the minute globules
of liquid are considerably reduced in temperature almost immediately they
reach the surface of the plant. For outdoor work the only difficulty would
be to maintain a large supply of liquid at a sufficiently high temperature
to render it effective when applied to the eggs of insect pests.

Chrysalides. In most cases these are to be found at rest in the soil.
The chrysalis, or pupa as it is also called, is the stage of development

172 Commercial Gardening

following that of the larva, maggot, or caterpillar, and preceding that of
the perfect insect. When the larva has eaten and destroyed a certain
amount of plant tissue, and has attained its full size, it then prepares to
take a rest for a certain period. It exudes a secretion out of which a
leathery protecting coat is formed, and it proceeds by a series of jerks to
pull this coat over its body from the bottom upwards, much in the same
way as if a man tried to pull a tight-fitting sack over himself from the feet
upwards, until he could tie it over his head. While this process is going
on, many larvae hang by a silken cord from the bough of a tree, or shrub,
or leaf, afterwards dropping down to the ground and burying themselves
in the soil at certain depths. Other larvae, however, spin cocoons in which
they pupate and go to rest in the soil, in crevices of walls, &c.

The periods at which various insects go to rest in the soil vary according
to their nature and habits, some being dormant either in spring, summer,
autumn, or winter, while others are active and destructive. It is in this
period of inactivity that the cultivator has the key to destroying the pests.
There they are resting quietly in the soil, and so long as they are undis-
turbed there is every chance that they will come forth in the perfect
insect stage to carry on mischief. Not only are the pests free from severe
frosty weather by being buried in the soil, but what is of more importance
is that they are also out of the reach and out of sight of the birds, whose
beaks in most cases are either too short or too tender to pierce the soil
covering the pupae.

It is therefore to the treatment of the soil that the cultivator must pay
more attention if he wishes to stop the mischief of these pests at the foun-
tain head. So long as the soil is left uncultivated, so long are the pests
quite safe from frost or birds. As soon, however, as the spade, fork, plough,
or hoe is used to turn up the ground, then and not till then will the grower
receive the assistance of nature's pest destroyers, the birds thrushes,
blackbirds, starlings, rooks, robins, sparrows, magpies, finches, owls,
swallows, poultry, &c., that are ever on the watch to pick up any choice
morsels of diet in the way of chrysalides or grubs that are brought
within their reach. Birds are of the utmost assistance to the gardener;
they render him valuable services free of charge, and are only too glad
of having a free feed placed at their disposal. A thrush or blackbird will
probably account for hundreds of grubs of various insect pests in the course
of a day, if the ground has been turned up so that they are readily detected.
Even the cost of digging the soil should not be debited to the birds, but to
the cultivator himself, as it is he who obtains the additional advantage
of having a larger supply of nitrates, phosphates, potash, fresh air, and
other essential plant foods placed at the disposal of his crops. As some
pests are dormant in the soil at every season of the year the wisest plan
therefore to secure their eradication is to keep the upper layer stirred with
the fork, spade, hoe, or scarified as often as the growing crops will permit.
The hoe is probably the most convenient for keeping the surface of the
soil in a loose and friable condition after digging or trenching. Its constant

Insect Pests

173

use will prevent any pests from going to sleep too long, as they will be
brought to the surface and exposed to the keen sight of the birds. The
hoe, therefore, may be regarded not only as better than the hose pipe or
water pot for keeping moisture in the soil, but it must also be considered
as a far superior and more effectual destroyer of ground pests than most
of the insecticides or earth powders recommended for this purpose. The
work of hoeing between the crops will of course entail expense, but the
money spent in this way will be found to yield more satisfactory results
than twice the amount spent in misapplying insecticides of doubtful
efficacy. The cultivator has to consider whether it will be better for him
to stir the soil frequently, so as to expose the various grubs to his friends
the birds (at the same time liberating food, keeping down weeds, and con-
serving moisture), or whether he will allow the soil to remain untilled and
infested with pests that will in due course compel him to spend a good
deal of money in washes and sprays, or lose his crops altogether. After
all, the whole question is a matter of pounds, shillings, and pence, and
the cultivator will find it more advantageous in every way to spend
his money in frequent digging and hoeing operations, if he wishes to
secure clean, healthy crops that are free from attacks of noxious in-
sects. The advantages of cultural operations have been already discussed
at pp. 101 to 107.

Table of Insect Pests. The following tabulated statement of the
various insect pests may be of use to the cultivator. Special stress is
laid upon the Period of Rest (chrysalis stage) column. That is when
the soil should be kept stirred up with the hoe, even if it cannot be
dug with the spade or the fork. It is of course understood that one of
the objects in stirring the soil is to enable the birds to get at the
grubs. The column indicating Period of Destruction (the larval stage),
is useful as indicating the period when the various washes and sprays
are likely to be most effectual.

INSECT PESTS OF FEUITS, FLOWERS, AND VEGETABLES

Name of Pest.

Besting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

American Blight (Schi-
zoneura lanigera, fig.
92).

Winter.

July to Oct.

Stems and roots of Apple trees.
Caustic washes in winter, and
methylated spirits or paraffin in
summer.

Ants.

Jan. to Dec.

Troublesome in fruit- and plant-
houses. Trap with sweet liquids,
and strew lime about nests.

Aphides. See Green and
Black Fly.

Apple Aphis and Ap-
ple Sucker (Aphis and
Psylla Mali).

Aug. to May.

May to July.

Attack flower buds and leaves.
Syringe with lime and salt, or
nicotine and quassia solutions.

174 Commercial Gardening

INSECT PESTS OF FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest.

Resting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Apple - blossom Weevil
(A nthonomus porno-

Winter.

Spring to
Summer.

Attacks Apple buds, and afterwards
the leaves. Grease-banding and

rum, fig. 97).

hoeing in autumn and winter; also

apply caustic wash before buds

break in spring.

AppleandCurrantClear-

Nov. to May.

June to Nov.

Grubs feed upon stems of the plants

wing Moth ( Trochilium

and the pupae nest in the crevices.

myopceforme, fig. 103).

Use nicotine or quassia washes in

summer, and caustic washes in

winter, rubbed well into bark.

Apple Mussel Scale (My-

Winter.

May to Aug.

Bark and branches of Apple and

tilaspis pomorum, fig.

other fruit trees. Apply caustic

93).

washes in winter.

Apple-pith Moth (Tine-

Winter.

Spring to

Early in year caterpillars tunnel

ina).

Autumn.

into pith of shoots and fruit spurs,

and pupate from June onwards.

Spray with nicotine washes early

in year, and cut back shoots in

winter.

Apple Sawfly (Hoplo-
campa testudinea).

Aug. to Mar.

April to July.

Attacks flowers of Apple, and after-
wards fruit. Destroy diseased fruit

and stir ground frequently with

hoe. Strew quicklime over sur-

face.

Asparagus Beetle (Crio-

Sept. to June.

June to Sept.

Attacks Asparagus shoots. Knock

ceris Asparagi, fig. 94).

off with stick, and strew lime

and soot over ground in advance.

Spray with nicotine, or dust with

hellebore powder.

Asparagus Jfly (Platy-

Sept. to April.

April to Aug.

Larvae bore into heads and stems

parea poeciloptera).

of young shoots and work down-

wards. Cut and burn the stunted

yellowish or brown stems, and

syringe early in season with paraf-

fin emulsion.

Bean Beetles (Bruchii*

Oct. to April,

May to Oct.

Examine affected seeds and burn.

granarius and B. ruf,-

in the seeds.

manus, fig. 95).

Beet Carrion Beetle (Sil-

Sept. to May.

May to Sept.

Woodlice-like larvae attack young

pha opaca).

plants. Keep under with nicotine

or quassia sprays and frequent

hoeing.

Beet Fly (Anihomyia

Sept. to May.

May to Sept.

The maggots feed upon the leaves

Betas).

of Beet. Remedies as for the

Beet Carrion Beetle.

Black Aphis, Black Dol-

Autumn to

May to Sept.

Attacks the shoots of Broad and

phin, Collier Blight,

Spring.

Long Pod, Dwarf or French, and

&c. (Aphis Rumicis).

Runner Beans. Syringe with

quassia and nicotine solutions in

advance, and keep ground hoed.

Infested shoots should be taken

off and burned.

Black or Vine Weevil

Mar. to July.

Aug. to

Attacks the roots, shoots, leaves,

(Otiorhynchus sidcatw,

Spring.

and flowers of various plants fre-

tig. 152).

quently the Strawberry and Vine.

Trap by shaking from Vines on

to cloths and burning. Cultivate

well in the open.

Fig. 93. Apple Mussel Scale (Mytilaspis
pomorum)

Fig. 92. American Blight (Schizoneura lanigera)

Fig. 94. Asparagus Beetle (Crioeeris Asparagf)
Larva and eggs magnified.

Fig. 95. Bean Beetles

1, Bruchus granarius (nat. size); 2. magnified.
3 Section of infested Bean. 4, Maggot (nat size);

6, enlarged. 6, Pupa (nat. size); 7, enlarged. 8, In-
fested Bean germinating. 9, Bruchus rufimanus
(nat. size) ; 10, enlarged. 11, Infested Pea. 4, 5, 6,

7, are common to both species.

X-300

Fig. 96. Bulb Mite (Rhizoglyphus echinopus). Dor-
sal and Ventral surfaces. The detached sucker-plate
magnified 300 diameters. (After Michael.)

Fig. 97. Apple-blossom Weevil (Anthonomus
pomorum)

176

Fig. 98. Cabbage Butterfly (Pirns Rapce)

I, Small White Cabbage Butterfly. 2, Caterpillar.
8, Tupa.

Fig. 99. Cabbage Fly (Anthomyia Brassicce)

1, Larva of A. Brassicce. 2 and 3, Pupae (nat. size
and magnified). 4, A. radicum (magnified). 5, Nat.
size. 6-9, A. tuberosa, larva and fly (nat. size and
magnified).

Fig. 100. Cabbage Gall Weevil (Ceutorhynchus
sulcicollis)

1, Earth case of the larva. 2, Case in its chamber
(magnified). 3, Stem with galls.

Fig. 101. Carrot Fly (Pxila Rosce)

I, Larva; 2, magnified. 3 and 4, Larvae appearing
from the galleries excavated in the Carrot. 6, Form
of pupa ; 6, magnified. 7 and 8, The Fly (nat. size
and magnified).

Fig. 102. Cabbage Moth (Slamestra Brassiere)
1, Moth. 2. Caterpillar. 3, Chrysalis.

176

Fig. 103. Apple and Currant Clear-wing Moth
(Trochilium tipultforme), and Larva

Insect Pests

INSECT PESTS OF FRUITS, FLOWERS, AND VEGETABLES (Cont.)

177

Name of Pest,

Resting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Brown -tail Moth (Par-
thesia chrysorrhaea).

Oct. to May.

May to Oct.

The hairy larvae feed upon fruit and
forest trees. Nest in leaves in

winter. Spray with arsenate of

lead, &c.

Bulb Mite (Rhizoglyphus

Jan. to Dec.

Mites attack bulbs of Eucharis and

echinopus, fig. 96).

under glass.

other plants, causing red blotches.

Badly infested bulbs should be

burned. Others should be washed

in carbolic, lysol, cyllin, or paraf-

fin solutions.

Cabbage Aphis (Aphis
Brassicce).

Winter to
Spring.

Spring to
Autumn.

Attacks Turnips and Cabbage crops
generally. Spray with nicotine

or quassia washes, and hoe fre-

quently.

Cabbage Butterfly
(Pieris Brassicce, P.

Oct. to Mar.

April to Sept.

Caterpillars attack various Cabbage
crops. Ground should be well cul-

Rupee, &c., fig. 98).

tivated, and quassia or nicotine

sprays may be used. Hand picking
advisable for small patches.

Cabbage Flea, Blue

Autumn to

Spring to

Cultivate soil well in autumn and

(Haltica consobrina).

Spring.

Autumn.

winter, and also between crops in

summer.

Cabbage Fly (Anthomyia
Brassicce, fig. 99).

Dec. to Feb.

Mar. to Nov.

Grubs attack fleshy roots of Turnips,
Radishes, Cabbages, Cauliflowers,

&c., and cause leaves to turn

yellow and wilt. Badly infested

plants should be burned. The

best remedy is frequent hoeing

amongst crops when possible.

Cabbage Gall Weevil

Oct. to Feb.

Mar. to Sept.

Small white maggots attack lower

(Ceutorhynchus sulci-
collis, fig. 100).

portion of stems of Cabbages, Brus-
sel Sprouts, Cauliflowers, Turnips,

and others, and cause pea-like

swellings. Best remedy is to hoe

ground frequently between crops.

urn all infested stems in autumn.

Cabbage Moth (Mames-
tra Brassicce, fig. 102).

Winter and
early Spring.

Summer and
Autumn.

Caterpillars destroy Cabbage crops
in summer and autumn. Cultivate

between crops in dormant season,

and use lime and soot over ground.

CabbagePowdered-wing

Autumn to

Spring to

Cabbage crops attacked. Remedies

Fly (Aleyrodes prole-
tella).

Spring.

Autumn.

as for Cabbage Moths and Butter-
flies.

Cabbage-root Fly (Phor-
bia brassicce).

Oct. to Mar.

April to Oct.

Attacks roots of Cabbage crops.
Remedies as for Cabbage Gall

Weevil.

Carnation Maggot (Hy-

Winter and

July to Sept.

Cylindrical maggots pierce down

lemyia nigrescens).

Spring.

centre of Carnation and Pink

stems. Spray with nicotine washes

about July, and destroy badly

affected plants. Hoe between

crops frequently in autumn.

Carrot Aphis (Aphis

Autumn and

June to Aug.

Attacks Carrot leaves. Spray before

Dauci).

Spring.

June with paraffin emulsion, and

hoe frequently.

Carrot - blossom Moth

Autumn and

July to Sept.

Attacks flowers of Carrots and Par-

(Depressaria Pastina-

Winter.

snips. May be caught with tarred

cella).

sacks, or killed by hellebore powder.

VOL. I.

1 7 8

Commercial Gardening

INSECT PESTS or FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest.

Resting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Carrot Fly (Psila Rosen,

Dec. to Feb.

Mar. to Dec.

Maggots attack roots of Carrots,

fig. 101).

and can only be kept down by

frequent hoeings to expose them

to birds. Infested roots should be

burned. Spray early with paraf-

fin emulsion.

Carrot-seed Moth (De-

Autumn and

July, Aug.

Devours flowers and seeds of Car-

pressaria depressella).

Winter.

rots and Parsnips, especially latter.

Spray with paraffin emulsion early

in season a few times.

Celery and Parsnip Fly
(Acidia heraclei or

Oct. to April.

April to Sept.

Eggs laid upon leaves of Parsnips
and Celery hatch a grub that pene-

Tephritis Onopordinis,

trates tissues. May be prevented

fig. 106).

by spraying with paraffin emulsion

before April, and at intervals after-

wards. Infected leaves must be

collected and burned. Cultivate

soil well, and strew with lime or

soot.

Celery-stem Fly (Rio-

Oct. to April.

April to Sept.

Tunnels down stalks and makes

phila Apii).

rusty marks. Remedies as for

Celery Fly.

Cherry Aphis (Myzus

Autumn to

Summer.

This is the Black Fly of Cherries.

Cerasi).

Spring.

Trees must be well syringed with

nicotine or quassia solutions.

Cherry Sawfly. See Pear

Sawfly.

Chrysanthemum Leaf-

Oct. to Mar.

April to Oct.

Chiefly attacks Chrysanthemum and

miner (Phytomyia ni-

Marguerite leaves, the maggot bor-

gricornis, figs. 104 and

ing between the tissues. Preven-

105).

tion and cure as for Celery Fly.

Cockchafer or May Bug

Jan. to Dec.

Large fleshy white grubs that take

(Melolontha wdgaris).

three years to attain full size. They

feed on roots of fruit trees, Roses,

&c., and do much damage. The

perfect beetles feed on leaves of

Apple and other trees in May and

June. Digging brings grubs up to

birds, but they should be collected

when possible and burned. Per-

fect insects should be shaken from

trees on to sheets, collected, and

burned.

Cockroach (Blalla orien-

Jan. to Dec.

Destroys floWers of various kinds.

tally).

May be trapped in glasses with

beer, molasses, &c. Houses should

be cleaned and limewashed.

Codlin Moth (Carpo-
capsa Pomonella, fig.

Autumn to
Spring.

June to Sept.

Eggs laid in Apple flowers, and
maggots afterwards spoil fruit.

107).

Collect all diseased fruits and

burn. Spray with Paris green,

arsenate of lead, &c., when trees

are in bloom. Cleanse stems with

caustic wash in winter. Hoe

ground frequently during autumn

and winter.

Cranefly. See Daddy

Longlegs.

179

Fig. 108. Currant Aphis (Myzus Ribis)
A, Male. B, Apterous female. 0, Winged female.

Fig. 109. Currant-shoot Moth (Incmvaria capitella)

1 Moth (magnified). 2, Moth (nat. size). 3, Caterpillar
(magnified).

Fig. 110. Currant Gall Mite (Eriophyes
Ribis)

1, Infested bud. 2, Mite (greatly enlarged).
3, Mite (younger stage).

Fig. 111. Daddy Longlegs or Craneflies
(Tipula oleracea and T. paludosa)

1, Eggs. 2, Maggot. 3, Pupa-case vacated
by the gnat of Tipula oleracea. 4, Female of
Tipula paludosa.

Fig. 112. Diamond-back Moth (Ptutella cruciferarum)

180

1, Caterpillar ; 2, Eggs ; 3, Moth (all natural size).
4, 5, Moth (magnified), at rest and flying.

Insect Pests

181

INSECT PESTS or FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest.

Besting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Currant and Gooseberry
Sawfly (Nematus Ri-

Sept. to Mar.

April to Sept.

Larvae eat leaves of Red Currants
and Gooseberries. Dust with lime,

besii, fig. 119).

sulphur, soot, hellebore, &c. Cul-

tivate soil well from October to

April to bring up pupae for birds.

Currant Aphis (Myzus
Ribis, fig. 108).

Autumn and
Winter.

Spring and
Summer.

Troublesome pests on the under sur-
face of leaves of Red, White, and

Black Currants. Syringe well with

nicotine solutions, and cultivate

ground with hoe.

Currant and Apple
Clear- wing Moth ( Tro-

April to June.

Oct. to April.

The grubs pierce the young wood
and feed upon the pith. The

chilium tipuliforme,

affected shoots should be cut off

fig. 103).

and burned. Spray with nicotine

washes, &c., in June to prevent

eggs being laid by female.

Currant Gall Mite

Winter.

April to Oct.

Attacks young flower buds of Black

(Eriophyes [Phytoptus]

Currant, and causes "big bud".

Ribis, fig. 110).

Pick off big buds, and dust with

lime and sulphur two or three

times in spring.

Currant -root Aphis

Winter.

Spring to

Attacks roots of Black and Red

(Schizoneura fodiens).

Autumn.

Currants. Cultivate soil well, and

occasionally drench with soapy

water.

Currant Scale, White

Nov. to Mar.

April to Oct.

Attacks Black, Red, and White

Woolly (Pvlvinaria

Currants, especially when grown

Ribesice).

on walls or fences. The pest forms

whitish woolly masses and webs.

Apply caustic washes in winter, and

paraffin emulsion early in year.

Currant-shoot Moth (In-

Oct. to April.

April to Sept.

The caterpillars feed on the pith of

curvaria or Tinea capi-

young shoots of Red and White

tdla, fig. 109).

Currants. Cut off diseased shoots

and burn. Spray with nicotine,

&c., in May, when female lays eggs.

Daddy Longlegs or

Oct. to April.

May to Oct.

The maggots, known as "leather

Cranefly (Tipula oler-

jackets ", eat the roots of many

acea and T. paludosa,

plants, and infest Turnips, Beet,

fig. 111).

Potatoes, &c. Deep cultivation, hoe-

ing, and encouragement of birds are

the best remedies. Otherwise trap

with turnips, beet, potatoes, &c.

Dart Moths (A gratis

Oct. to May.

May to Nov.

Caterpillars eat roots of all kinds of

exclamations, A. sege-

plants, feeding at night. Strew

tum, figs. 113 and 114).

lime and soot over soil, and hoe

frequently.

Diamond - back Moth

Oct. to May.

June to Sept.

Green or yellowish caterpillars eat

(Plutella maculipennis,

away leaves of Cabbages, Turnips,

P. cruciferarum, fig.

&c. Dust with soot or lime, or

112).

spray with quassia and soft-soap

solutions. Cultivate soil in dor-

mant season.

Earwigs (Forjicula auri-

Winter.

Spring to

Various flowers and fruits at night-

cularia).

Autumn.

time. Stir ground frequently, and

trap with pieces of cloth, hay, &c.,

in pots. Deep cultivation and fre-

quent hoeing excellent remedies.

182

Commercial Gardening

INSECT PESTS OF FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest.

Besting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Eelworm, Nematoid

Jan. to Dec.

Minute snake-like larvae that prey

Worms (Tylenchiis de-

upon the roots of many garden

vastatrix, Heterodera

crops, notably Cucumbers, Toma-

radicicola, H. Schachti,

toes, Phloxes, Gardenias, Carna-

fig. 116).

tions, &c. Apply lime or soot or

basic slag to badly infested soil,

and avoid too rich organic manures.

See article on "Cucumber", Vol.

EucharisMite. (See Bulb

IV.

Mite.

Figure -of -8 Moth (Di-

Sept. to May.

May to Aug.

Larvae attack leaves of Apple and

loba cceruleocephcUa,

other fruit trees. Spray with

fig. 118).

Paris green, arsenate of lead, &c. ,

in May and June. Cultivate the

soil in dormant season.

Fruit-tree Beetle (Scoly-

Oct. to April.

April to Oct.

Small larvae tunnel between the

tus rugulosus).

bark and wood of Apples, Pears,

Plums, Cherries, Peaches, Nectar-

ines, and other Rosaceous trees.

Cut down and burn badly infested

trees. Use hot caustic wash in

winter, and cultivate soil well in

summer.

Garden Chafer (Phyllo-

July to April.

May to July.

Larvae feed upon leaves of Roses,

pertha horticda).

fruit trees, &c. Spray with quas-

sia, nicotine, &c., in May and

June. Hoe during summer to

bring up pupae for birds.

Garden Pearl Moth

Oct. to June.

June to Oct.

Larvae feed on leaves of Cabbage

(Pionea forficcdis).

crops, Turnips, Horse Radish.

, Dust with lime or soot, or spray

with nicotine or other washes.

Cultivate soil well up to June.

Ghost-swift Moth (Hepi-
alus Humuli, fig. 115).

May to July.

Aug. to April.

Caterpillars feed upon roots of Let-
tuces, Strawberries, Hops, Nettles,

&c. , and cause leaves to wilt. Hoe

frequently from August to April,

and destroy all nettles and other

weeds.

Goat Moth (Cossus lig-

Winter

Spring to

Fat caterpillar, 3-4 in. long, with a

niperda).

months.

Autumn.

goat-like smell, pierces trunks of

fruit and forest trees, and lives in

them for three years. Thrust wire

into burrows, or inject strong

petroleum washes.

Gooseberry Sawfly. See

Currant Sawfly.

Grape Moth (Ditula an-

Various.

Found on many trees, but chiefly

gustiorana, fig. 120).

destructive to Grape fruits. Shake

caterpillars on to tarred paper, and

burn.

Green and Black Fly

Winter in

Jan. to Dec.

Numerous garden plants infested

(Hhopalosiphon Dian-
thi, Siphonophora Pe-

open air.

under glass.

with various species of green fly,
in the open air and under glass.

largoni, S. Pisi, Aphis

Fumigate under glass. Syringe

Cratcegaria, &c.).

with quassia and soft soap or nico-

Julus Worms. See Mil-

tine solutions in open air.

lipedes.

Fig. 113. The Common Dart Moth (Agrotis segetum)
1, Moth flying. 2, Caterpillar.

Fig. 114. The Heart-and-dart Moth (Agrotis

exclamationis)

I, Moth at rest. 2, Caterpillar. 3, Earthen case
surrounding chrysalis. 4, Chrysalis.

Fig. 115. Ghost-swift Moth (Hepialug Humuli)

1 and 2, Eggs (nat. size and magnified). 3, Caterpillar.
4, Chrysalis. 5 and 6, Moths, male and female (nat.

size).

183

Eelworms or Nematoid Worms (Tylenchus)

1, Transverse section of Carnation leaf, showing
eelworms in the tissue. 2, Portion of Carnation leaf
(magnified 50 times), showing worms escaping from
the eggs and also fully developed. 3, Surface view
of leaf of Oncidium, showing egg-containing pustules
bursting. 4, Transverse section of leaf of Oncidium,
showing eggs containing worms ready to hatch out
in pustules on both surfaces, and worms in the
tissues. 5, Portion of root of Cucumber (highly
magnified), showing a cyst containing eggs in the
centre; also eggs at the lower right-hand corner
from which the worms are escaping, and worms that
have escaped.

Fig. 117. Small Ermine Moth (Hyponomeuta padella)
I, Caterpillar. 2, Moth. 3, Larva in web.

Fig. 118. Figure-of-8 Moth (Diloba cceruleocephala)
A, Moth. B, Caterpillar.

Fig. 119. Gooseberry and Currant Sawfly
(Nematus Ribesif)

1, Shoot of Gooseberry. 2, Eggs. 3, Larva.
4, Pupa. 5, Perfect Insect.

Fig. 120. Grape Moth (Ditula angustiorana)
1, Moth. 2, Larva and details. 3, Chrysalis (all enlarged).

184

Insect Pests

INSECT PESTS or FRUITS, FLOWERS, AND VEGETABLES (Cont.)

185

Name of Pest.

Resting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Lackey Moth (Clisio-
campa neustria, fig.

July to April.

April to July.

Larvae feed upon leaves of fruit and
forest trees. Eggs on branches

121).

should be looked for in April and

destroyed. Spray with quassia

and soft soap in May and June.

Collect cocoons from trees in July

and August, and burn.

Lettuce Fly (Anthomyia

Oct. to April,

April to Oct.

Attacks flowers of Lettuce plant

Lactucce).

in Lettuce

when grown for seed. Cultivate

heads.

well, and destroy all old Lettuce

stems.

Lettuce - root Aphis
(Pemphigus lactuarius).

Winter.

April to Sept.

Larvae pass from leaves to roots
and feed upon them. Lime, or

soot, or soft soapy water good

remedies; also frequent hoeing.

Magpie Moth (Abraxas
grossulariata, fig. 123).

Oct. to July.

Aug., Sept.

Larvae feed upon leaves of Red and
White Currants, Gooseberries.

Examine bushes for pupae which

hang down from Sept. to July, and

burn all collected. Spray bushes

with Paris green, arsena,te of lead,

&c., in Aug. and Sept. before first

attack.

March Moth (Anisop-

teryx cescularia). See

Winter Moth for habits

and remedies.

May Bug. See Cock-

chafer.

Mealy Bug (Dactylopius
adonidum).

Jan. to Dec.

A hothouse pest of stove and green-
house plants, Vines, &c. Paraffin

washes and fumigation.

Millipedes or Julus

Jan. to Dec.

The larvae (often called wireworms)

Worms (Species of

feed upon roots of Potatoes,

Julus and Polydes-

Onions, Carrots, Turnips, Cab-

mus, fig. 131).

bages, &c. Best remedy frequent

hoeing, and strewing lime or soot

on ground, and avoid rank manure.

Mole Cricket (Gryllo-

Oct. to May.-

June to Sept.

Larvae attack roots of vegetable

talpa vulgaris, fig. 125).

crops, and also caterpillars and

other insects, and may be dis-

covered by small heaps of mould.

They may be caught by placing

hot manure in deep holes, in Sept.,

and when insects have nested they

may be dug out. Frequently hoe

ground.

Mottled Umber or Great

Nov. to April.

April, May,

Larvae feed upon leaves of Apples,

Winter Moth (Hyber-

and June for

Pears, Plums, Roses, &c. In Oct.

nia defoliaria, fig.

larvae ;

and Nov. eggs are laid on shoots,

122). See also " Win-

Oct. , Nov. for

which should be washed with caus-

ter Moth ", fig. 144.

egg laying.

tic soda; ground should be well

hoed during summer. Grease-

banding useful in Oct.

Narcissus Fly (Merodon
Narcissi, fig. 124).

Nov. to Feb.

Mar. to Nov.

Maggots attack bulbs of Narcissi.
Affected bulbs are best burned.

Hoe soil between crops, and place

saucers of sweet solutions between

Narcissi to trap perfect flies.

1 86

Commercial Gardening

INSECT PESTS OF FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest.

Resting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Nematoid Worms. See

Eelworms.

Nut Weevil (Balaninua

Autumn to

Spring and

Cultivate the soil, and shake dis-

nucum).

Spring.

Summer.

eased fruits on to cloths beneath

trees in May and June, and de-

stroy.

Onion Fly (Anthomyia

Autumn to

Spring to

Larvse penetrate Onion bulbs and

ceparum or Phorbia

Spring.

Autumn.

cause leaves to flag. Destroy

cepetorum).

affected bulbs and hoe ground

frequently between plants. Strew

lime or soot, and spray with pe-

troleum emulsion early in the

season.

Onion Fly, Brassy (Eu-

Oct. to Mar.

April to Sept.

Grubs attack bulbs of Onions during

merua oeneus, fig. 126).

season. Destroy injured bulbs,

and cultivate soil with hoe in

summer and winter.

Parsnip Fly. See Celery

Fly.

Pea and Bean Weevil

Sept. to Mar.

Mar. to Sept.

Weevils destroy leaves of Peas and

(Sitones lineata, 8. cri-

Beans. Dust with lime or soot,

nita, fig. 132).

or spray with nicotine or quassia

solutions.

Pea Moth (Endopisa
proximana).

Sept. to May.

May to Sept.

Peapods are attacked, the cater-
pillars feeding on the peas in sum-

mer, and escaping into ground in

autumn. Cultivate soil by digging

and hoeing.

Peach Aphis (Aphis
Amygdali, Myzus Per-

Sept. to April.

April to Sept.

Attacks young leaves and causes
them to curl. Fumigate under

sicce).

glass. Syringe frequently with

nicotine washes in open air.

Peach Scale (Lecanium

Winter.

Spring and

The young shoots of Peach trees.

Persicce).

Summer.

Paraffin emulsion and caustic wash

in winter.

Pear -leaf -blister Moth

Oct. to April.

April to Oct.

Pale-green larvae mine the leaves of

(Lyonetia Clerckella,

Apples, Pears, Cherries, forming

fig. 130).

tunnels and blisters. Spray with

Paris green, nicotine, arsenate, or

other washes in April, May, and

June. Cultivate soil well in win-

ter and spring.

Pear-leaf Mite (Phytop-

Autumn to

Spring to

This minute pest penetrates leaf

tus Pyri, fig. 127).

Spring.

Autumn.

tissues of Pear, causing spots and

blotches. Remedies for Currant

Gall Mite may be tried.

Pear Midge (Cecidomyia
or Diplosis pyrivora).

Autumn to
Spring.

Spring and
Summer.

Eggs are laid in blossoms, and the
yellow maggots feed on young

fruits, sometimes twenty to thirty

in one fruit. Spray with Paris

green, arsenate of lead, &c. , before

flowers open. Collect diseased

fruit, and cultivate soil well in

dormant season.

Pear Oyster Scale (Dias-

Winter.

May to Aug.

Paraffin emulsion in summer, and

pis ostreceformis, fig.

caustic wash in winter, to cleanse

128).

the infested bark.

Fig. 121. Lackey Moth (Clisiocampa neustria)
1, Eggs. 2, Caterpillar. 3, Moth.

Fig. 122. Mottled Umber Moth (Hybernia
defoliaria)

1. Male Moth. 2, Female. 3, Caterpillar
(nat. size).

Fig. 123. Magpie Moth (Abraxas grossulariata)
and Larva

Fig. 124. Narcissus Fly (Aferodon Narcissi)

1, Infested bulb ; a and 6, grub holes. 2, Grub.
3, Pupa. 4, Insect.

Fig. 125. Mole Cricket (Gryllotalpa vulgaris)

Fig. 126. Brassy Onion Fly (Eumerus ceneus)

1 and 2, Grub (nat. size and enlarged). 3 and 4, Pupa
1, Eggs. 2 and 3, Larvw of different ages. 4 Mature (nat. size and enlarged). 6 and 6, Insect (enlarged
Insect. and nat. size).

187

Insect Pests

189

INSECT PESTS OF FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest.

Resting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Pear Sawfly (Eriocampa
limacina).

Oct. to May.

May to Oct.

Black slimy caterpillars feed upon
under surface of Pear leaves, Roses,

&c. Spray freely with nicotine and

quassia washes early in season.

Cultivate soil well in dormant sea-

son.

Pear Sucker (Psylla
Pyri, fig. 129).

Winter.

Spring and
Summer.

Young leaves of Pears when coming
into bloom. Nicotine washes in

summer, and caustic in winter.

Phylloxera vastatrix.

See Vine Louse.

Plum Aphis (Aphis

Sept. to April.

May to Aug.

Mealy - covered pests suck juices

Pruni).

from leaves of Plums, and leave

excreta on surface, and curl leaves.

Spray freely from May onwards

with nicotine, quassia, or other

solutions.

Plum Grub (Carpocapsa

Oct. to May.

June to Sept.

Caterpillars attack fruits, and pierce

funebrana, fig. 134).

flesh to stone. Treat as for Plum

Sawfly.

Plum Sawfly (Hoplo-

Autumn to

Mar. to July.

Feeds upon young Plum fruits and

campa fulvicornis).

Spring.

destroys them. Collect fallen fruits

and burn. Cultivate from autumn

to spring.

Plum Weevil. See Red-

legged Garden Weevil.

Raspberry Beetle (By-

Autumn and

Spring and

Fruits of Raspberry. Burn all dis-

turus tomentosus, fig.

Winter.

Summer.

eased fruit, and hoe well round

136).

stools at intervals during the

year.

Raspberry Moth (Lam-
pronia rubiella, fig.

Oct. to April.

April to Oct.

The pink larvae, about in. long,
feed on flower and leaf buds and

135).

pith of shoots. Destroy injured

shoots which may contain grubs.

Cultivate soil well in dormant

season, and dust freely with lime

or soot.

Raspberry Weevil (Oti-

orhynchus picipes).

See Red-legged Garden

Weevil.

Red - legged Garden
Weevil (Otiorhynchus

May to July.

Aug. to April.

Larvae feed upon roots of Goose-
berries, Currants, Raspberries,

tenebricosus).

Strawberries, Vines. Hoe ground
frequently, and dust with lime or

soot.

Red Spider (Tetrany-

Autumn

Jan. to Dec.

Tiny mites infesting under surface

chius telarius ; also
species of Bryobia

to Spring
outside.

under glass.

of leaves of many plants in the
open air and under glass. Syringe

and Tenuipalpus).

thoroughly with clean water or

nicotine solution.

Root Aphis (Trama
troglodytes).

Oct. to April.

May to Oct.

Feeds upon the roots of Jerusalem
Artichokes and other plants. Best
kept down by cultivation and hoe-

ing.

Rootgall. See Eelworm.

190 Commercial Gardening

INSECT PESTS OF FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest.

Resting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Rose Aphis (Siphono-

Oct. to Mar.

April to Sept.

Attacks leaves and young shoots of

phora Rosce, S. rosa-

Roses in open air and under glass.

rum).

Syringe freely with nicotine or

quassia solutions.

Rose Chafer (Cetonia

Oct. to Mar.

April to Oct.

The fat, hairy, whitish grubs feed

aurata, fig. 139).

on roots of various plants, and the

beetles feed on the flowers of Roses,

Strawberries, &c. Remedies as for

Cockchafer Grub.

Rose Sawflies (Hylotoma

Oct. to Mar.

April to Sept.

Larvae eat leaves of Roses. Some

Rosce, Emphytus cine-

Rose Sawflies roll the leaves up

tiis, figs. 133 and 137).

into shelters. Syringe early and

frequently with nicotine or quassia

washes. Cultivate from Oct. to

March.

Rose Tortrix (Lozotcenia

Aug. to Mar.

April to July.

Larvae roll up leaves of Roses and other

Rosana).

Elants, and feed upon the flower

uds. Remedies as for Sawflies.

Silver Y Moth (Plusia

Oct. to Mar.

April to Sept.

Green caterpillars feed upon leaves

gamma, fig. 140).

of all kinds of plants. Spray with

nicotine and other washes early;

dust with lime or soot. Cultivate

ground well in dormant season.

Slugs and Snails (Limax
ater, L. agrestis, Helix

Jan. to Dec.

Troublesome under glass and in open
air. Catching by hand under glass,

hortensis).

or strewing stages or soil with soot

or lime as in open air. Use hoe

frequently outside, and encourage

thrushes, blackbirds, &c.

Slug Worms (Eriocampa

Oct. to June.

July to Oct.

Larvae destroy leaves of Pears,

limacina, E. Rosce, fig.

Roses, &c. See remedies under

138).

Pear Sawfly.

Small Ermine Moth

July to Mar.

April to June.

Caterpillars live in colonies in webs,

(Hyponomeutapaddla*,

and destroy leaves of Apples, Haw-

fig. 117); H. euony-

thorns, Euonymus, &c. Syringe

mella, H. malinella.

freely in May with Paris green,

nicotine, or other poisonous washes.

Collect cocoons from plants in July

and August. Cultivate ground

during dormant season.

Snowy Fly (Ahyrodes

Jan. to Dec.

Minute larvae infest leaves of Cu-

vaporariorum).

cumbers, Ferns, Tomatoes, &c.,

and perfect white insects soon

develop. Fumigate and syringe

with nicotine.

Spittle Fly or Frog

Oct. to April.

May to Sept.

Larvae embedded in spittle-like froth

Hopper (Aphrophora

suck juices from tender shoots of

spumaria, fig. 142).

many garden plants. Brush off

pests or squeeze between fingers.

Afterwards spray with nicotine or

quassia solutions.

Thrips (Thrips minutis-

Autumn to

Jan. to Dec.

The dull yellow larvae of several

sima, T. pisivora, T.

Spring

under glass.

species attack under surface of

cerealium, &c., fig. 148).

in open air.

leaves of many crops in open air

and under glass when air is very

dry. Syringe plants under glass

with water or quassia solutions;

also in open air; and hoe freely.

335

Fig. 137. Larvae of Rose Sawfly (Hylotoma Rosce)

Fig. 138. Slug Worm or Sawfly (Eriocampa
limacina), showing enlarged insect, and larva
on leaf.

Fig. 139. Rose Chafer (Cetonia aurata)
1, Beetle. 2, Caterpillar. 3, Cocoon. 4, Pupa.

Fig. 140. Silver Y Moth (Plusia gamma)

I, Eggs. 2, Caterpillar. 3, Chrysalis in cocoon.
4, Moth.

Fig. 141. The Turnip Fly or Beetle (Phyllotreta
nemorum)

1 and 2, Insect (nat. size and magnified). 3, Insect
feeding. 4 and 5, Eggs on under side of leaf. 6 and 7,
Maggot advancing in growth. 8 and 9, Maggot full-grown
(nat. size and magnified). 10 and 11, Pupa (nat. size and
magnified).

Fig. 142. Spittle Fly (Aphrophora spumaria),
showing insects and frothy spittle on shoot.

192

Insect Pests

INSECT PESTS OF FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest

Besting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Turnip Fly (Phyllotreta

Oct. to Mar.

April to Sept.

Maggots penetrate leaf tissues of

nemorum, fig. 141).

Turnip crops, and mature in a

week. Spray early with nicotine

or quassia washes, and at frequent

intervals hoe the soil to bring up

the pupae for the birds.

Turnip Gall Weevil

Oct. to Feb.

Mar. to Sept.

Remedies as for Cabbage Gall

(Ceutorhynchus pleuro-

Weevil.

stigma, fig. 143).

Turnip Mud Beetle

'Winter.

Spring to

Beetles and grubs attack all parts

(Helophorus rugosus).

Autumn.

of Turnip crops, especially tops of

bulbs. Hoe frequently and dress

with lime or soot, and burn dis-

eased plants.

Turnip Sawfly (Athalia

Oct. to Mar.

April to Sept.

Larvae eat leaves of Turnips from

spinarum).

edges to ribs. Numerous brood in

one season. Remedies as for Tur-

nip Fly.

V Moth (Halia Wavaria,
fig. 149).

Sept. to April.

May to Aug.

Pale -green caterpillars feed upon
leaves of Gooseberries and Cur-

rants, and often destroy them.

Hand picking, or spraying bushes

early with strong nicotine or

quassia solutions.

Vapourer Moth (Orgyia
antiqua, fig. 150).

Oct. to April.

May to Oct.

Hairy caterpillars feed upon leaves
of Pears, Cherries, Roses, &c.

Spray with nicotine, arsenate, and

other washes, except for fruit

trees. Shake caterpillars on to

cloth and crush. Hoe frequently

in winter and spring.

Vine Louse (Phylloxera

Various.

This pest attacks roots and leaves

vastatrix, fig. 151).

of Vines sometimes, and does much

damage. Bisulphide of carbon in

soil is recommended. Diseased

leaves should be burned. Soil

should be kept stirred.

Vine Scale (Pulvinaria

Jan. to Dec.

Nicotine washes and fumigation.

Vitis).

Caustic wash when Vines are

dormant.

Wasps.

Sept. to May.

May to Sept.

Attack all kinds of ripe fruits. Trap
with sweet solutions, and plug nest

holes up at night with gunpowder,
vaporite, carbon disulphide, &c.

Winter Moth (Cheima-
tobia brumata, fig. 144) ;
and the

July to Oct.

Oct. to June.

Wingless females crawl up stems of
Apples, Pears, Plums, Cherries,
&c. , from Oct. to Dec., and lay eggs.

Winter Moth, Great

The caterpillars devour leaves and

(Hybernia defoliaria).
See fig. 122.

flowers in April and May. Grease-
band in Oct. and onwards, but dig

or hoe well from June to Oct. to

bring up pupae for birds.

Wireworms or Click
Beetles (Elater or Ag-
riotes lineatiis, E. ob-

Aug. to Mar.

April to July.

The larvae or wireworms infest many
soils, especially grassland, and at-
tack roots of all kinds of plants,

scurus, E. sputator, fig.
146).

and live from three to five years.
Deep cultivation and hoeing to

encourage birds. Also trap with

potatoes, carrots, beet, turnips, &c.

VOL. I.

194

Commercial Gardening

INSECT PESTS OF FRUITS, FLOWERS, AND VEGETABLES (Cont.)

Name of Pest.

Resting Period
(Pupa Stage).

Destructive
Period (Cater-
pillar and Perfect
Insect Stage).

Plants Attacked and Remedies.

Woeberian Tortrix (Se-
masia Wceberana, fig.
153).

Winter.

Spring to
Autumn.

Fruit trees, generally beneath the
bark, producing cankerous wounds.
Winter washes if trees are not
badly injured. Otherwise cut
down.

Wood Leopard Moth
(Zeuzera JEsculi).

Caterpillars burrow in stems of fruit
and other trees, and live one to
two years. Remedies as for Goat
Moth.

Wood Lice (Armadillo,
mdgaris, &c., fig. 147).

Jan. to Dec.

Eat tender shoots of Maidenhair
and other Ferns, destroy flowers,
&c. Trap with potatoes, carrots,
turnip, &c., or mix phosphorus
paste and bran, and strew in runs ;
afterwards sweep up dead bodies.

Woolly Aphis. See
American Blight.

Yellow Aphis (Siphono-
phora lutea).

Jan. to Dec.

Attacks flowers of Orchids at all
times. Careful fumigation and
vaporizing.

Yellow-tail Moth (For-
thesia auriflua).

Oct. to Mar.

April to Sept.

Black humpy larvse feed on Apple
and other fruit trees. Spray with
nicotine or quassia, and cultivate
soil in dormant season.

Yellow-tmderwing Moth
( Triphcena pronuba,
fig. 145).

Oct. to Mar.

April to Sept.

Caterpillars eat leaves of vegetable
crops. Remedies as for Cabbage
Butterfly.

Fig. 149. V Moth (Httlia
Wavaria)

(natural size.)

Fig. 151. Vine Louse (Phylloxera vastatrix)

1, Boot galls. 2 and 3, Forms of larva. 4, Winged
female. 6, Portion of diseased leaf. 6, Enlarged section
of excrescence on leaf.

196

Fig. 150. Vapourer Moth (Orgyia antiqua)
1, Male. 2, Female. 3, Caterpillar.

Fig. 152. Black or Vine Weevil
(Otiorhynchus sulcatus)

1, Weevil. 2, 3, Larva (nat. size and magnified).
4, Pupa. 5, 0. picipes.

Fig. 153. Wocberian Tortrix (Sewasia
Wceberana)

SECTION VII
Garden Friends

Although the gardener may look upon the great majority of insects
as enemies, he must not conclude that there are no friends of his in
the insect world. There are several, and it may be well to put them
on record here.

In the first place the honey bee (Apis mellifica) does an enormous
amount of good to the fruit-grower by fertilizing the pistils in the flowers
of his Apple, Pear, Plum, Cherry and other fruit crops, thus ensuring
a bounteous harvest, if the spring frosts have not interfered with the
process of fertilization at a
critical period. Whenever the
fruit-grower can manage to have
a few hives of bees in his gardens
he will find it advantageous from
a commercial point of view, and
apart from the quantities of
honey he may take from the
hives for his own use or for sale.
Bees, of course, are not only
valuable for securing the fertil-
ization of fruit trees and bushes
of all kinds, but they perform
similar good offices for almost

every flowering plant. In a lesser degree the Humble Bees (Bombus ter-
restris and R lucorum) also do good work in fertilizing flowers, but they
are often charged with taking a short cut to obtain the nectar by piercing
the base of the flowers of Broad Beans and Runner Beans, instead of
entering by the mouth of the blossoms and thus secure the deposition
of the pollen from their bodies on to the stigmas.

Ladybirds. There are over twenty species of these known in Britain,
but two especially are very common in gardens, viz. Coccinella (or Adalia}
bipunctata and 0, septempunctata. The first-named (fig. 154, 7), is black
with scarlet wing cases, and two conspicuous black spots; the second (C.
septempunctata) is larger (fig. 154, 9) and has seven black spots on the

197

Fig. 154. Ladybirds

1, Eggs, natural size, on a leaf. 2, Egg magnified. 3,
Larva, with the line 4 showing natural size. 5 and 6, Pupae.
7, Coccinella bipunctata. 8, C. dispar. 9, C. septempunctata.

198

Commercial Gardening

wing cases. Another species (C. dispar) is shown at 8, fig. 154. The
larvae or maggots of these Ladybirds, shown at 3, fig. 154, are slate-col-
oured and yellowish, and remind one of miniature alligators in appear-
ance. It is these larvae that feed largely on aphides, and thus help the
gardener by suppressing them. The maggots and ladybirds therefore

Fig. 156. Devil's Coach Horse, or Fetid Rove Beetle (Ocypw olenn)

1, Larva. 2, Full-grown beetle on the wing. 3, Head
enlarged, showing the powerful jaws.

Fig. 156. Violet Ground
Beetle (Carabus violaceus)

should never be destroyed in gardens, and all children should be instructed
as to their value.

The Devil's Coach Horse. This is also known as the Fetid Rove
Beetle (Ocypus olens). It has a long, narrow, deep -black body, and preys
upon insects with great energy, and will soon tear an earwig to pieces. The
larvae also feed upon insect pests. During the month of May the insect
is in the pupa or chrysalis state, but is very frequently
S/N. / /' me ^ w ^h * n au tuinn. Fig. 155 shows the full-grown

^ - - - ' * beetle and the larval stage, and the enlarged head shows
the powerful jaws.

The Violet Ground Beetle (fig. 156) is known as
Carabus violaceus. It is an insect-eating beetle often
found under stones and clods of earth, and is very
often killed by those who are ignorant of its garden
value. It has a violet-black body and rather coarsely
granulated wing cases, and should be readily recognized
by all cultivators as a friend.

The Tiger Beetle (Gicindela sylvatica), shown in
fig. 157, is a black beetle with a violet under surface,
and is very active in search of prey. The common
Tiger Beetle (C. campestris) inhabits banks and sandy
commons. It is about \ in. long, and is green in colour with six white
spots on each wing case, including the round one on the disk. The larva
has a large head and a hump on its back near the tail, bearing two spines,
by means of which it anchors itself in its burrow, waiting for its prey.
Other kinds of insect-eating beetles are those known under the names
of Pterostichus madidus and P. cupreus, often called Sun Beetles, owing

Fig. 157. Tiger Beetle

(Cicindela nylvatica)

PERENNIAL PHLOXES

i. Crepuscule. 2. Coquelicot. 3. Tapis Blanc.
(Three-fcmrtlis natural size)

Garden Friends

199

Fig. 158. Hawkflies

1, Scceva balteata; 2, Larva with greenfly in its
jaws; 3, Pupa. 4, Scatva PyrasM; 5, Larva; 6,
Pupa. 7, Scceva Ribesii.

to the activity they display in running to and fro in the sunshine in
search of food. The last-named (P. cupreus) is about in. long, with
a green, bronzy, brassy or bluish-black body, the under surface being
black.

Frog's, Toads, Lizards. These much - maligned animals must be
regarded amongst the best friends of the cultivator. The Frog (Rana
temporaria) feeds upon insects and small slugs, and will also devour beetles
and fairly large insects. The Toad
(Bufo vulgaris) will also destroy large
numbers of insects, including slugs,
beetles, woodlice, and even worms.
The toad will only eat living things,
and therefore makes sure of this con-
dition by waiting until its victim shows
signs of life. At the least movement
the toad darts out its tongue and

swallows its prey at a gulp, except in
the case of worms, which require a
little more attention. The Common
Lizard (Zootoca vivipara) lives upon
various kinds of beetles and insects
that are injurious to garden plants.

Hawkflies. These two- winged insects of the genus Scaeva are very
numerous from July to September, and have received their name from the
fact that they hover over flowers like a hawk; but they vary the hovering
by suddenly darting about. They are deadly enemies to aphides, including
American Blight. The eggs of the Hawkflies are laid amongst the aphides,
upon the bodies of which the young Hawkfly maggots feed voraciously,
each one being capable of destroying one hundred aphides in an hour. The
Hawkfly maggots are to be recognized by their relatively large, fleshy, and
thin-skinned bodies resting among the aphides or slowly crawling about.
They are whitish, pale green, or yellow, and in some cases lined or streaked
with orange. When fully developed the maggots
assume a pear-like shape, and attach themselves by
the tail to some part of a plant and then pupate.
In a few days the perfect insect comes forth again
to carry on the war amongst the aphides. The
perfect insects and the larvae, therefore, as shown
in fig. 158, should never be destroyed, if possible,
as they perform such beneficial work.

Ichneumon Flies. These are found all over the kingdom, and are
chiefly engaged in destroying destructive caterpillars of various kinds.
Some deposit their eggs in the caterpillars or the pupae. The Ichneumon
maggots feed upon the soft parts until the caterpillar or chrysalis is about
to undergo a change. This, however, it cannot effect, owing to the injuries
received, and it consequently dies. Fig. 160 shows on the left how a large

Fig. 159. Ichneumon Fly
(magnified)

2OO

Commercial Gardening

caterpillar is overpowered with the maggots of the Ichneumon Flies; while
on the right a caterpillar is covered with their cocoons. Amongst the prey
of these Ichneumon maggots may be mentioned the Cabbage Butterfly, the

caterpillar of the Death's Head
Moth, the various kinds of
aphides, wire -worms, and no
doubt other grubs. There are
so many kinds of Ichneumon
Flies, all helpful to the gar-
dener, that it becomes a difficult
problem to know them from
the enemies. Fig. 159 shows
an Ichneumon Fly highly mag-
nified, and it will be observed
that it bears a resemblance to
the wasps and bees.

Laeewing' Flies. These
flies belong to the genus Chry-
sopa, and, as may be seen from
fig. 161 (1), derive their name
from the delicate veining of
their wings. The eyes are
golden green, very large and
conspicuous, with two long,
slender feelers on the head.

The female is about | in. long and larger than the male. The larvae shown
at 3 and 4, in fig. 161, are very voracious, and will devour large numbers
of aphides, including American Blight, in a very short time, and will even
attack caterpillars about f in. long. These hairy larvae develop from eggs

that are laid singly on hair-like
stalks in rows and clusters, as
shown in fig. 161, at 2, these
slender stalks often projecting
about 1 in. from the surface of
the leaves or branches to which
they are attached. After the
larvae have fully developed they
change into pupae and reach the
perfect-insect stage in about three
. _. weeks during the summer months.

1, Chrysopa perla. 2, Eggs. 3, Larva. 4, Larva magnified.

5 and 6, Cocoon (natural size and magnified). The later broods pupate during

the winter months in cocoons, as
shown at 5 and 6 in fig. 161, and become perfect in spring.

Ear-shelled Slug*. Although most slugs are injurious to vegetation,
there is one genus which provides flesh-eating slugs that will feed upon
other slugs and even worms. The British Ear-shelled Slug (Testacella

Fig. 160. Caterpillar devoured by the Larvae of Ichneumons,
and Caterpillar covered with their Cocoons

Fig. 161. Laeewing Fly

Garden Friends

2OI

halotidea), shown at fig. 162, is one of these. It is about 2 in. long, deep
yellow in colour, and may be recognized by a small ear-shaped shell
attached to its back, just above the tail. During the daytime it nests in
the soil, and is often turned up when digging; but at night-time it roves
abroad in search of the common slugs and snails, and makes war upon
them. A foreign species, from South Europe (T. Maugei), has become
naturalized near Bristol, and
may spread throughout the
milder parts of the kingdom in
time if encouraged. It has a
dark-brown body with a larger

shell than the native Species. Fig. 162. Ear-shelled Slug (Testacella hulotidea)

Cultivators should become ac-
quainted with these friendly molluscs, and should educate their employees
to take care of them.

Spiders. The true spiders, being perfectly harmless to plants, and
living upon various kinds of insects, should never be destroyed by gar-
deners, although their webs and nests often present a very untidy appear-
ance if allowed to remain in potting sheds, greenhouses, lofts, &c. The
common garden spider, known as Epeira diademata, is a pretty, greyish
insect beautifully speckled or spotted with white on the back of its
roundish abdomen. It lives upon moths and flies of various kinds, and
will easily defeat a vicious wasp in a straight fight by
winding its silken cords around it.

A kind of leaping spider (Epiblemum scenicum),
shown in fig. 163, leaps about amongst plants, and
pounces upon its prey. It is grey in colour with oblique
white bands on the back of the abdomen and legs.

The Weasel. Amongst animals the weasel must be
regarded as a friend of the cultivator, as it destroys
rats, mice, voles, rabbits; but it also destroys poultry,
and its assistance is generally regarded as a doubtful
blessing.

Centipedes. Although belonging to the same group as the Millipedes
or Julus worms the Centipedes (Geophilus subterraneus) are not harmful
to crops. On the contrary they are beneficial, inasmuch as they feed on
insects, caterpillars, worms, snails, and slugs; they are active and flesh-
eating insects, and should be preserved for the good they do.

From what has been said above it may be taken that although nature
has sent many insects to plague and worry the cultivator of plants, it has
also provided antidotes in the way of birds of all kinds, Ichneumon Flies,
Ladybirds, Lacewing Flies, Tiger and other Beetles, Frogs, Toads, and
Lizards, Hawkflies, Spiders, and even Slugs, by which they may be kept
in check. Unfortunately, with the many poisonous washes now in use it
is possible that when applying them the cultivator is slaughtering his
friends as well as his enemies. Indeed he is practically not even on

Kig. 163. Epiblemum
scenicum (twice natural
size)

202 Commercial Gardening

speaking terms with his friends, and in many cases would not recognize
them as such even if he were to see them. It would be worth while to
make a special effort to cultivate colonies of Ladybirds, Ichneumon Flies,
Lace wing Flies, and Hawkflies especially, as these by sheer force of numbers
would readily suppress the various destructive aphides and caterpillars.
When one comes to realize the wonders of the insect world, and how some
kinds prey upon others, one is forcibly reminded of the truth of the
couplet, that

" Large fleas have little fleas upon their backs to bite 'em,
Little fleas have lesser fleas and so ad infinitum ".

SECTION VIII
Fungoid Diseases

Notwithstanding the enormous amount of mischief done by insect pests
to the various crops grown in the open air and under glass, that caused
by fungoid diseases is if anything more considerable, and necessitates a
large outlay every year to keep the diseases in check. While one may
by clean cultivation and attention to natural laws keep insect pests largely
in check, the very best cultivators may be caught napping when a fungoid
disease begins to ravage his crops. Slugs, snails, caterpillars, moths, butter-
flies, beetles, &c., after all are enemies that can be detected by an observant
cultivator, and measures for their suppression can be taken in good time.
Not so, however, with the various fungoid diseases that cause so much
mischief. In the early stages these are hidden from the eye, being of
microscopic proportions, and it is not until plants or fruits have been in
a measure destroyed that the disease is observable. The tiny speck or
blotch on a leaf or fruit to-day may develop into a large and putrid mass
of vegetable tissue to-morrow, filled with thousands of spores which will be
blown about by the wind, thus to carry disease and death to other plants.

The true fungi consist of a large number of stemless cryptogamic plants,
the chief feature of which is that, unlike the higher Cryptogams (such as
Ferns), and the flowering plants proper or Phanerogams, they lack green
colouring matter or chlorophyll. Owing to this absence of green colour-
ing matter in the tissues, fungi are unable to utilize sunlight as a source
of energy and food assimilation. They cannot take in carbonic acid gas
from the atmosphere, nor can they absorb nitrogen. Indeed fungi give
off carbonic acid gas as a waste product. They must therefore obtain their
nourishment in a form already prepared for their reception either by
living plants or by dead ones. Hence there are two distinct groups of
fungi: (1) those that exist on or derive their food from dead plants or
organic material are known as "saprophytes", and (2) those that obtain
their food from living plants are called " parasites". As a rule the parasitic
fungi are most dangerous to the cultivator, because they attack his living
plants in various stages, and unless checked or eradicated are likely to
inflict serious losses. Intermediate between the true parasitic fungi and
the true saprophytic ones comes a class that first of all causes portions of
living plants to die by secretions or ferments of some kind, and then gains
an entrance into the living tissues, and eventually causes their death.

203

204 Commercial Gardening

According to their mode of attack the parasitic fungi are divided into
two groups: (1) the epiphytic and (2) the endophytic. The latter penetrate
the tissues of the plant and there develop their mycelium; the former
vegetate on the surface and spread their mycelium over it.

The mycelium constitutes the typical vegetative structure of a fungus,
and is of a thread-like and much -branched character. The threads of
which the mycelium consists are called "hyphae". In some forms of
fungi, however, there are no threads, but separate cells, as in the Yeast
Plant. The mycelium (or its hyphse) may be one-celled, or it may be
divided transversly into separate compartments, each of which may con-
tain several nuclei from which in due course spores may develop. When
the hyphse of some fungi branch between the cells of plants, they often
develop. Generally speaking the visible part of a fungus is the " fruiting"
part, from which fresh spores are distributed when ripe, and are carried
from one place to another by the wind and water. In such fungi as the
Common Mushroom, the so-called Toadstools, the Beef-steak Fungus, and
many other conspicuous plants, the spores may be readily collected if the
"caps" of the fungi are placed on sheets of paper in a warm room, and
may be easily seen with the naked eye. In the case of the fungi that
attack our plants, however, the spores and even the entire fungus pro
ducing them are very minute, and require powerful microscopes to distin-
guish some of their special feeding or absorbing organs, called "haustoria",
which penetrate the cell walls and absorb the nourishment from the cells.

It is thought that fungi originally came from the Algse, and have
undergone various changes in the process of evolution. A fungus begins
life from some kind of a spore of a very simple character, quite distinct
in character and structure from the seed of a flowering plant. When the
spore of a fungus germinates on a suitable plant tissue it swells up by
absorbing moisture and sends out a germ tube, which penetrates the host
plant and as it lengthens and branches becomes the mycelium or spawn.
After a time the mycelium begins to give off fresh spores, varying in form,
development, numbers, &c., according to the different kinds, and known
by specialists under different names. The various spores of fungi may
arise from the sexual union of two distinct cells, or they may originate
asexually by means of "swarm" spores. Under certain unfavourable
conditions the spores of fungi may remain dormant for a considerable
time, but possess the power of germinating afterwards under favourable
conditions. It is the resting power of the spores of many fungi that con-
stitutes the chief danger to the cultivator, as he never knows how many
thousands of them may be sleeping in his soil. For certain pot plants,
like Ferns, it is possible to sterilize small quantities of soil by pouring
boiling water over it, or by roasting it in a furnace; but such operations
are quite beyond the range of practicability with large quantities of soil.
The nearest approach to sterilizing the soil in the open air, and preventing
the spread of fungoid diseases (as well as insect pests), is to cultivate
frequently and strew powdered sulphur over any areas known to be badly

Fungoid Diseases

205

infected. Sulphur seems to be the great and most reliable antidote to
fungoid attack, and this fact is so well recognized that it appears in one
form or another in many of the best fungicides.

Another peculiar feature about some fungi is that they exist in two
or three different forms or stages, and on two or three different plants.
It is now well known that the " Smut" of corn exists in one stage on Bar-
berry bushes (Berberis), from which it passes into another stage and then
becomes injurious to corn crops. A somewhat similar state of affairs exists
with the Apple Rust and Pear Bust. The fungus that exists on Junipers
as Gymnosporangium clavariceforme passes from the Junipers and infests
Apples and Pears in the form known as Rcestelia aurantiaca, causing
orange -yellow or almost crimson patches on the leaves. Farmers now
know that the proximity of Barberry bushes may lead to an attack of
" Smut" on their corn, and fruit-growers know that Junipers may lead to
the Rust of Apple and Pear leaves.

These cases are mentioned with the object of showing that there is
cause and effect with fungoid attacks as with insect attacks, and once the
real cause is known it becomes easier to check the spread of the disease.

In the following table some of the chief fungoid diseases afflicting
fruits and vegetables are given, so that the grower may see at a glance
the enemies he has to face. Further details will be found in Vol. Ill,
dealing with Fruit Crops, and in Vol. IV, dealing with Vegetable Crops.
The principal fungoid diseases afflicting Flowering Plants are referred to
in Vol. II, under the plants attacked.

FUNGOID DISEASES OF FRUIT TREES

Common and Scientific
Name of Disease.

Parts Attacked and Outward
Appearance.

Treatment, <fec.

Apple Black Rot. See
Quince Black Rot.

Apple Blight (Micro-
coccus amylovorus).

Apple Brown Rot
(Sderotinia or Moni-
lia fructigena).

Apple Canker (Nectria
ditissima).

Apple Powdery Mil-
dew (Podosphcera
oxyacanthce).

Apple Ripe Rot (Pent-
cillium glaucum).

Appears on bark in small spots,
which enlarge and kill the twigs
and branches. Flourishes also
on unripe fruit.

Attacks all parts, but chiefly
fruits, in circular lines of reddish
or yellowish pustules.

Attacks bark, and causes it to
die and form cracks. Increases
rapidly and prevents healing;
usually follows attacks of Ameri-
can Blight, the spores germinat-
ing in the wounds, and produc-
ing minute red balls in spring.

Attacks young shoots and leaves
with a white powdery mildew,
causing them to shrivel in time.

Attacks ripening fruits, and causes
them to rot.

Use caustic washes in winter, and
hot Bordeaux mixture and liver
of sulphur when fruits have set.
Disease also attacks Pears.

Gather diseased fruits and burn.

Use caustic washes in winter, and
methylated spirit, paraffin, &c.,
in summer for Blight, and wood
tar for the wounds.

Spray with hot Bordeaux mixture
or liver of sulphur on first ap-
pearance, and afterwards if
necessary. The disease also at-
tacks Pears, Hawthorns, Med-
lars, Mountain Ash.

Collect rotting fruits and burn.

2O6

Commercial Gardening

FUNGOID DISEASES OF FRUIT TREES (Cont.)

Common and Scientific
Name of Disease.

Parts Attacked and Outward
Appearance.

Treatment, &c.

Apple Ripe Rot or
Bitter Rot (Glceospo-
rium fnicliijenum).

Apple Rust (Gymno-
sporangium davarice-
forme).

Apple Scab or Black
Spot (Fiisidadium
dendriticum).

Cherry Spot (Fusicla-
dium Cerasi).

Coral Spot Disease
(Nectria cinnabar-
ina).

Currant Leaf Blight
(Glceosporium ribis).

Gooseberry "Die
Back" (Botrytis cine-
rea or Sderotinia
Fuckeliana)-.

Gooseberry Mildew
(American) (Sphce-
rotheca Mors-Uvce).

Gooseberry Mildew
(European) (Micro-
sphcera grossularice).

Grtipe,False,or Downy
Mildew (Plaamopara,

viticola).

Grape Vine Anthrac-
nose or Bird's-eye
Rot ( Phoma [Sphace-
loma] ampelinum).

Grape Vine Brown
Mildew (Sderotinia
Fuckdiana).

Appears first as brown spots,
which soon bear pustules of a
white or pinkish colour, turn-
ing to black. Imparts a bitter
flavour to the fruit.

Forms scurfy bunches or cluster
cups on the under surface of
leaves, with orange, yellow, or
crimson blotches on upper sur-
face.

Attacks leaves, young shoots, and
fruits,first as dirty greenish spots,
then enlarging, and blackening,
and cracking surface, and de-
forming leaves and fruits.

Stems, leaves, fruits.

Fungus appears in conspicuous
bright coral-red warts on dead
or dying stems of Apples, Pears,
Red and Black Currants, and
numerous forest trees.

Attacks stems and leaves in small
red-purple spots in summer, be-
coming irregular and grey with
dark -purple margins, and de-
stroys leaves.

Attacks all parts of Gooseberries,
and kills them in a short time;
the leaves first of all turn yel-
low, then shrivel and die. Very
prevalent.

Attacks young shoots and leaves
in early summer in form of white
mildew, and may spread to fruits.
In autumn and winter brown
felt-like patches with black dots
on shoots indicate the disease.

Forms white powdery mildew on
leaves in early summer, but is
rarely harmful.

Appears as white patches on the
under surface of leaves, and
sometimes on stems and fruits.

Mycelium of fungus penetrates
leaves, green bark, and fruit,
and kills tissues. Small grey
spots at first, becoming sharply
defined with dark-brown edges,
resembling birds' eyes.

Attacks leaves and fruits in brown
patches.

Grapes, Pears, and Peaches also
attacked. The " rot " increases
rapidly amongst stored fruit.
Spray with hot Bordeaux mix-
ture or liver of sulphur early in
season, after young fruits have
set, and at intervals afterwards.

This disease grows in one stage on
Junipers, and is transmitted to
Apple trees in another (Rcestelia)
stage. Destroy Junipers if neces-
sary, and spray early in season
withBordeaux orliver-of-sulphur
mixtures. Also attacks Quinces.

Spray with hot Bordeaux or
liver-of-sulphur solutions before
flowersopen, andafteryoungfruit
has set. Burn badly diseased
fruits, and cultivate soil with hoe.

Remedies as for Apple and Pear
Spot.

All diseased shoots should be
burned to prevent spores attack-
ing healthy plants the following
year.

Spray early in season with hot
Bordeaux or liver-of-sulphur
solutions at intervals.

No remedy known beyond grub-
bing up and burning affected
plants. Cultivate soil well, and
dust heavily with powdered sul-
phur if fresh Gooseberries are to
be planted.

Prevalent in parts of Kent and
other places. Spray with liver-
of-sulphur (1 Ib. to 32 gal. water)
recommended, but apparently
useless; burn prunings in winter.

The best remedy is plenty of air
and light; otherwise spray with
hot Bordeaux mixture or liver
of sulphur.

Remedies as for Grape Vine Pow-
dery Mildew below.

Spray with hot Bordeaux or liver-
of-sulphur solutions when first
noticed, and at intervals if neces-
sary. In winter wash stems
with caustic solution.

Remedies as for mildew below.

Fungoid Diseases

207

FUNGOID DISEASES OF FRUIT TREES (Cont.)

Common and Scientific
Name of Disease.

Parts Attacked and Outward
Appearance.

Treatment, &c.

Grape Vine Powdery
Mildew ( Uncinula
spiralis).

Grape Vine, White
Rot (Coniothyrium
diplodidla).

Melon " Nuile " (Sco-

lecotrichum meloptho-

rum).
Peach Black Spot

(Cladosporium car-

pophilum).

Peach Brown Rot

(Moniliafructigena) .

Peach Leaf Curl (Exo-
ascuK deformans).

Peach Mildew (Sphce-
rotheca pannosa).

Pear Leaf Blight (En-
tomosporium macula-
turn).

Pear Leaf Fungus
( Gymnosporangium
clavaricfforme) .

Pear Scab or Spot
(Fusicladium pyri-
num).

Plum and Cherry
Black Knot (Plow-
riyhtia morbosa).

Plum Leaf Blight (Cy-
lindrosporium Padi).

The mycelium attacks the epider-
mal 'cells of leaves and young
fruits, and forms white spots,
which after a time become brown
withered spots. The leaves
wither, but the untouched parts
of fruits grow, and eventually
burst and shrivel.

Sometimes attacks fruits, causing
them to brown and shrivel, and
later on assume a dull silvery
appearance with minute white
pimples the fruit of the fungus.

Attacks fruits and destroys tissue.

The mycelium runs over surface
of leaves and fruit, causing pale
spots, which become confluent,
and sometimes cause fruits to
crack.

This is the same as the Apple,
Cherry, and Plum Rot.

Leaves curl or pucker, and fall.
The mycelium rests in tissues of
leaves, flowers, and shoots, and
attacks leaves in early stages.

The mycelium forms a thin white
coating on leaves and fruit, which
become moro or less deformed.

Leaves, stems, and fruits. The
spores hibernate in depressions
in the bark, and pustules appear
on young leaves early in spring,
causing them to drop. Dark
spots appear on fruits, which
become hard, and corky and
cracked.

Attacks leaves of Pears and Juni-
pers.

Causes brownish spots on leaves
and fruits, also on bark of twigs.

Causes crusty wart -like excres-
cences on twigs and branches,
which become deformed and
thickened into knots.

The young leaves become spotted
and perforated by holes, caused
by the falling out of withered
spots. Young trees soon de-
foliated.

Sulphur vaporized in the houses
is the best recognized remedy.
The mildew may also be killed
by applying forcibly fine sprays
of hot liver-of-sulphur solution
early in season.

Best remedy is to remove and
burn diseased bunches of fruit,
and vaporize sulphur as for
ordinary Vine Mildew.

Dust freely with powdered sul-
phur.

Spray early in season with hot
Bordeaux or liver-of-sulphur
mixtures. Also attacks Plums
and Cherries.

Remedies as for Apple Brown Rot.

Spray with hot Bordeaux or liver-
of-sulphur mixtures, and collect
and burn as many diseased leaves
as possible, and also diseased
fruits. Strew powdered sulphur
over freshly turned soil.

Spray with hot liver-of-sulphur
solution, or dust with sulphur '
before fruits set.

Wash stems with hot caustic soda
in winter, and spray with hot
Bordeaux or liver-of-sulphur
solutions as soon as leaves ap-
pear in spring. The Quince is
attacked by same disease.

Remedies as for Pear Spot.

Spray with hot Bordeaux or
liver-of-sulphur solutions before
flowers open, and after young
fruits have set.

Wash well with hot caustic solu-
tions in winter, and with hot
Bordeaux mixture in spring
when young leaves appear. Cut
out and burn any knotted shoots.
Cherries are attacked with the
same disease.

Remedy as for Pear Leaf Blight
above.

208

Commercial Gardening

FUNGOID DISEASES OF FRUIT TREES (Cont.)

Common and Scientific

Parts Attacked and Outward

Name of Disease.

Appearance.

Treatment, &c.

Plum ' ' Pockets " (Exo-

Attacks the ovaries, leaves, and

Where the young shoots are con-

ascus Pruni).

shoots. Causes the fleshy part

siderably thickened and twisted,

of fruit to swell, while stone re-

they contain mycelium, and

mains stunted. The "pocket"

should be cut off and burned.

plums dry up and hang till

Spray when flower buds begin

autumn.

to swell, and afterwards, with

hot Bordeaux mixture.

Plum Rust (Puccinia

Attacks fruits of Plums, Peaches,

Spray early with eau celeste or

Pruni).

Apricots, Nectarines, Cherries,

ammoniacal copper carbonate.

Almonds.

Plum "Silver- leaf"
(Stereum purpure um) .

Leaves assume a glossy leaden ap-
pearance, and trees afflicted die

No sure remedy. Cut down in
summer (not autumn), and burn

in a few years.

at once. Dress soil with pow-

dered sulphur before replanting.

Quince Black Rot

The mycelium permeates and de-

Spray with hot Bordeaux or liver-

(Sphceropsis malo-

stroys the skin of the fruits of

of-sulphur solutions when fruit

rum).

Apples and Quinces, causing them

sets, or when flowers are open-

todryupand become mummified.

ing.

Raspberry Cane Rust

Attacks stems and leaves in small

Cut away old stems and decayed

or Anthracnose

reddish-purple spots, sunken in

remains after fruit is picked,

( Glososporium vene

surface, and often confluent.

and burn, as they often contain

turn or O. necator).

Ripening fruit remains small

the hibernating mycelium. In

and shrivels. The Blackberry

spring use hot dilute washes of

is attacked with same disease.

Bordeaux mixture.

Shot - hole Fungus

Appears on leaves as translucent

Peaches and Nectarines are mostly

(Cercospora circum-

spots, which eventually become

attacked, but Almonds, Cherries,

scissa).

yellow patches, through which

Apricots also. The best remedy

dark-coloured hair-like tufts pro-

seems to be to spray with the

trude and bear spores at the tips.

self - boiling lime - sulphur - soda

The diseased patches drop out

wash early in the season.

later on, leaving holes in the leaf.

Strawberry Leaf

Appears on the upper surface

Pick and burn badly affected

Blight (Sphcurella

as small reddish spots, which

leaves. Spray with hot Bor-

fragarice).

rapidly enlarge, the centres

deaux mixture in early summer,

withering and browning.

and dust sulphur freely over the

soil and foliage.

Young Fruit Tree
Fungus (Eutypdla,

Attacks young trees of Apples;
also Peaches, Apricots, Cherries,

Disease appears to be most preva-
lent on heavy badly tilled soils.

Pruna-stri),

and allied plants, wild and cul-

Therefore cultivate deeply, and

tivated. Causes premature yel-

dress with lime or basic slag, after

lowing and fall of leaves. After-

well-rotted stable manure has

wards elongated cracks appear

been added. Paint stems with 1

on bark in dense clusters. In-

Ib. of powdered quicklime mixed

fection takes place in late spring

with 5 gal. of soft soap reduced

and early summer.

to consistency of thick paint.

FUNGOID DISEASES OF VEGETABLES

Asparagus Rust (Puc-

Attacks stems.

Diseased shoots should be col-

cinia Asparagi).

lected and burned in autumn.

Bean, Kidney, Disease

Chiefly attacks young pods, but

Destroy diseased pods by burning,

(Colletotrichum Lin-

also leaves and stems. Brown

and dust plants with sulphur.

dermuthianum).

depressed spots, with a distinct

border, appear on pods.

Bean Rust (Uromyces

Appears on both surfaces of leaves

Not very harmful as a rule. Spray

Phaseoli).

as small round scattered spots,

early with liver-of-sulphur solu-

brown changing to black.

tion.

Fungoid Diseases

FUNGOID DISEASES OF VEGETABLES (Cont.)

Common and Scientific
Name of Disease.

Parts Attacked and Outward
Appearance.

Beet Heart Rot (Phyl-
(osticta tabiftca or
Sporideamium putre-
faciens).

Cabbage Crop Black
Rot (Pseudomonas
campestris).

Cabbage White Rust
(Cystopus candidus).

Celery Blight (Cerco-
spora, Apii).

Club Root (Plasmodio-
phora brassicce) ; also
known as ' ' Anbury "
and "Finger and
Toe ".

Cucumber Fruit Spot
(Cladosporium cu-
cumerinum}.

Cucumber Leaf Blotch
( Cercospora Melonis).

Hop Mildew (SpJice.ro-
theca Castagnei).

Mushroom Disease
(Hypomyces perni-
ciosus).

Onion Mildew (Per-
onospora Schleideni).

Onion Smut ( Urocystis
Cepulcn).

VOL. I.

The outer leaves wither, followed
by whitish spots with withered
tissue filled up with the my-
celium, which spreads inwards
and attacks the roots.

Bacteria attack lower leaves of
Cabbages, Cauliflowers, Brussels
Sprouts, Turnips, &c., and pass
into the stems, which become a
putrid evil-smelling mass. The
veins of diseased plants show up
as a black network.

Attacks the leaves, stems, and
flowers of all Cabbage crops, and
deforms them, covering them
with a dense white flour -like
mildew.

Causes yellowish spots on leaves,
turning to brown. The my-
celium grows between the cells
in leaves, and sends tufts of
conidiophores through stomata.
Parsnips are affected by same
diseases.

Attacks the roots of all Cabbage
crops, including Turnips, Rad-
ishes, Swedes, and Kohl-Rabi,
and causes deformed and putrid
masses.

Brown rotten depressions caused
on fruits of Cucumbers and
Melons.

Appears as small green spots on
leaves, gradually increasing in
size, and becoming brownish or
yellow, leaves often becoming
dry and shrivelled in twenty -
four hours.

Attacks all parts of plant, includ-
ing young inflorescences, and
thus destroys crop.

Attacks growing Mushrooms,
which become an irregular mass,
ultimately decaying into a pu-
trid mass with a disagreeable
pungent smell.

Cover.s tops of onions with a
greyish mouldy velvety coat,
and causes leaves to flag.

Attacks green leaves and subter-
ranean scales, forming brown
pustules and streaks.

Treatment, Ac.

Diseased plants should be taken
up and burned. Mangels and
Swedes are also attacked, the
disease appearing from the
middle of August onwards.

Diseased plants should be taken
up and burned, and the soil may
be dressed with powdered sul-
phur.

Diseased plants should be taken
up and Iburned, and all Cruci-
ferous weeds, like Shepherd's
Purse, &c. , should be suppressed
by good cultivation.

Spray early in season with fungi-
cides. The Celery Leaf Blight
caused by Septoria Petroselmi,
var. Apii, attacks leaves and
stems, and may be known by
small black spots.

The best remedy is fresh gas lime
or quicklime dug in when ground
is fallow ; or slaked lime or basic
slag when crops are on soil, or
about to be planted.

Causes the same as leaf blotch ;
remedies the same, all diseased
fruits being burned.

Chiefly caused by too high a tem-
perature, lack of fresh air, and
too much water. Remedy these
conditions and burn all diseased
leaves. Melons and Marrows
afflicted with same disease under
similar conditions.

Spray early in season with hot
Bordeaux mixture or liver of
sulphur, and dust freshly turned
soil freely with sulphur.

Diseased plants should be removed
and burned when seen, and better
ventilation should be given to
Mushroom houses, as foul air is
one of the chief causes of attack.
Before spawning for a fresli crop,
clean out old soil, and burn
brimstone or sulphur with closed
doors.

Young plants chiefly injured when
grown in badly drained soil, or
in low damp situations. Alter
these, and spray with fungicides.

Spray with liver of sulphur, or dust
soil and plants with powdered
sulphur earl}'. Transplanting to
fresh ground is beneficial. Badly
diseased plants are best burned.

2IO

Commercial Gardening

FUNGOID DISEASES or VEGETABLES (Cont.)

Common and Scientific
Name of Disease.

Potato Black Scab
(Chrysophlictis endo-
biotica); also known
as "Wart Disease",
"Cauliflower Dis-
ease", and "Canker
Fungus ".

Potato Disease ( Phyto-
phthora infevtans).

Potato Leaf Curl (Ma-
crosporium Solani).

Potato Scab (Oospora
Scabies).

Potato Stem Rot (Ba-
cillus phytophthorus).

Potato Winter Rot
(Nectria Solani).

Spinach Anthracnose
Colletotrichum Spin-
aceai).

Spinach Mildew (Per-
onospora effusa).

Spinach White Smut
(Entyloma Ellisi).

Tomato Bacterial Dis-

Tomato Black Rot or
Black Stripe (Macro-
ftporium Solani).

Tomato Sleepy Disease
(Fusarium ly coper -
sici).

Parts Attacked and Outward
Appearance.

Attacks tubers and stems, and
causes large irregular and mossy
outgrowths.

Attacks leaves, shoots, and
tubers, causing them to become
discoloured, brown-spotted, and
rotten.

Causes leaves to curl, and pre-
vents assimilation; forms irregu-
lar blackish velvety patches.

Attacks young tubers, forming
rough scattered patches on sur-
face, gradually enlarging.

The fungus causes the leaves to
flag and turn yellow, and then
to shrivel and die. The stems
are discoloured, and eventually
become black and rotten.

Fungus appears in white tufts on
stored tubers, and changes to
pale pink later on to produce
more spores, reducing tubers to
a rotten evil-smelling mass.

Appears at first as moist patches
on leaves, becoming minute
brown pustules, and eventually
grey dry areas.

Causes a violet -grey mildew on
under surface of leaves, and
yellowish blotches on upper.

Attacks leaves, and discolours
them.

Attacks fruits when about size
of a marble, and black blotch
rapidly increases in size, eventu-
ally reducing fruit to blackish
mass.

The fungus forms long blackish
stripes on the stems, irregularly
shaped blotches on the leaves,
and black blotches on the fruits.

The fungus is internal, and when
plants are nearly full-grown
causes leaves to droop and
change colour. The basal por-
tion of stem becomes mildewed,
and dull orange patches appear
all over.

Treatment, &c.

All diseased plants and tubers
should be burned. See article
on "Potatoes", Vol. IV.

Good culture is one of the best
remedies. See article on " Pota-
toes ", Vol. IV. Spray as a pre-
ventive with Bordeaux mixture
early in season.

Remedies as above for Potato
Disease.

Avoid "scabbed" seed and half-
rotted manure. Deep tillage is
the best remedy, and sulphur
should be freely dusted in
trenches if affection is feared.

Diseased plants should be burned.
Deep cultivation and wide plant-
ing, north and south, should be
adopted. See article on "Pota-
toes ", Vol. IV.

Storehouse should be well venti-
lated, dry, and cool. Tubers
should not be heaped up too
much, and should be well dried
before storing. A sprinkling
with powdered sulphur is useful
as a check.

Dust plants and soil freely with
powdered sulphur, and cultivate
deeply.

Avoid waterlogged or low damp
soils. Dress with slaked lime
and powdered sulphur if disease
appears, and cultivate deeply.

Dress soil and plants with pow-
dered sulphur.

No remedy for affected fruits be-
yond picking and burning.

Best remedy is to take up and
burn diseased plants.

Take up and burn diseased plants,
and freely dust soil with sulphur,
after pouring boiling water over
if possible.

SECTION IX
Fungicides and Insecticides

Owing to the attention that has been given to the various fungoid
diseases of fruits, flowers, and vegetables of late years, a large industry
has developed amongst chemists to supply remedies for checking or killing
the various diseases. What has already been said about the efficacy or
otherwise of insecticides at p. 167 applies with almost equal force to
fungicides. The use of these has increased enormously of late years, but
the various fungoid diseases seem to enjoy themselves as much as formerly
on our crops. Indeed the writer has seen some of the worst cases of
fungoid diseases in market gardens upon which large sums of money have
been spent annually in insecticides, while other gardens, upon which not a
farthing has been spent on either insecticides or fungicides, are practically
immune from fungoid diseases and insect pests. Apple trees and pear
trees that have been carefully sprayed for Fusicladium have had their
fruits attacked quite early in the season; while in other cases, where the
usual methods of cultivation were practised, but where no fungicides were
used, the fruits were perfectly free from fungoid attack.

The only fungoid diseases that seem to defy all fungicides and all efforts
to check or eradicate them appear to be the " Silver-leaf " of Plums and
the " Die-back " of Gooseberries. Some day, perhaps, when more is known
about these two terrible diseases, it may be possible to find a means of
destroying them. In the meantime Victoria and Gisborne Plums are
rapidly falling a prey to the " Silver-leaf " fungus (Stereum purpureum),
while Gooseberries are being mowed down wholesale in places by the
" Die-back " (Botrytis cinerea).

Just as many insect pests are undoubtedly due to inferior methods of
cultivation, it is possible that the prevalence of many fungoid diseases is
due to the same cause. The cultivator, therefore, who pays more attention
to the arts of cultivation and manuring his soil, and not so much perhaps
to the sciences of chemistry and entomology, will probably find his crops
more free from disease of every kind. At the same time, as it is beyond
the bounds of human possibility to keep fungoid diseases like that of the
Potato absolutely in check, he should be prepared to suppress any sudden

212 Commercial Gardening

outbreaks by means of fungicides that have been found more or less
effectual.

Fungicides are applied either in the form of sprays or washes, as dry
powders, or as vapour. So far as the sprays and washes are concerned
the grower will find fungicides applied in a hot or warm state much better
than in a cold one. The writer has carried out many experiments with
fungicides and insecticides dissolved in boiling water, and has applied them
in the form of a fine misty spray to outdoor crops without causing the least
injury to the plants, but often destroying the pests and diseases with one
good application. The reader must distinguish between applying an in-
secticide or fungicide boiling hot through a fine-spray nozzle, and dipping
the leaves and shoots of a plant in the same solution. When the hot liquid
is sent with force through a fine-spray nozzle, it impinges on the leaf or
stem surface in the form of tiny globules in a mist-like spray. A good deal
of heat is lost in transit, and the tiny globules are still further cooled to
air temperature almost as soon as they touch the leaf surface. They have,
however, retained a higher temperature than is healthy for the fungus or
insect pest; hence these are usually killed outright. In spraying large
areas, the only difficulty is to maintain the liquid up to a temperature of
212 F. or boiling-point, but this may be overcome by having a small
portable boiler and fire attached.

The following is a list of the most effective insecticides and fungicides
on the market at present:

1. Ammoniacal Copper Fungicide or Cupram. Recipe:

Copper sulphate (98 per cent) 1| oz.

Carbonate of soda (98 per cent) ... ... ... If

Ammonia solution (strongest) ... ... ... 12 fluid oz.

Water 12 gal.

Dissolve the copper sulphate and carbonate of soda separately, each in
| gal. water; pour soda into copper solution and stir well. When precipi-
tate has settled, pour off' clear liquid. Wash precipitate a second time,
and pour off" liquid when clear. Then add liquid ammonia to precipitated
copper carbonate, sufficient to dissolve it. Add water up to 10 gal.,
and the liquid will be read}' for use. It has properties similar to those
of Bordeaux Mixture. See also " Eau Celeste ".

2. Arsenate of Lead (Sugar of Lead). Formula (Strawson):

Acetate of lead (98 per cent) ... ... ... 2| oz.

Arsenate of soda (98 per cent) ... ... ... 1

Water to make ... ... ... ... ... 10 gal.

Place materials in water and stir till dissolved, when the liquid will be
ready for use. One pound of treacle or soft soap may be added, if desired,
to make the liquid adhere better. This mixture is now considered superior
to Paris Green, as it is much lighter and does not scorch the foliage. From
1 to 2 Ib. of arsenate of lead to 150 gal. water has proved effectual.

Fungicides and Insecticides 213

3. Bordeaux Mixture. Formula:

Copper sulphate (98 per cent) ... ... ... 2 Ib.

Lime (freshly burnt) ... ... ... ... 1 M

Water ... 10 gal.

Dissolve copper sulphate in 5 gal. water in wooden vessel. When lime
has slaked to a tine powder, mix it with remaining 5 gal. water, and then
pour into copper solution. Stir the mixture thoroughly to secure even
distribution. Bordeaux mixture is regarded as one of the most useful
and effective fungicides. To test the liquid add a few drops of potassium
ferrocyanide (1 oz. to 10 oz. of water), and if the liquid becomes brown
add more lime. To make a strong solution add an extra Ib. of copper
sulphate to 10 gal., and to make a weak solution reduce the copper sulphate
| Ib. from formula.

4. Carbon Bisulphide. This is a volatile and inflammable clear liquid,
which gives off an insect-killing vapour at a low temperature. The vapour
being heavier than air, it is advisable to apply the liquid at top of holes
when it is desired to eradicate ground pests. For vaporizing houses about
pt. of liquid is sufficient for 500 cub. ft. of space, and for ground pests
about 2 oz. poured into holes about 2 ft. apart is considered sufficient. It
appears to be a much more costly and less efficacious method of ridding the
soil of pests than turning up the soil with the spade or fork and exposing
the pests to the birds.

5. Caustic Wash or Winter Wash. There are several formulae for
making caustic winter washes to be applied to trees in a dormant condition.
These caustic washes cleanse the bark of fruit trees and bushes from such
parasitic plant growths as mosses, lichens, and algae, thus allowing them
to breathe more freely. If applied quite hot with a strong-haired brush,
the eggs of many insect pests are also destroyed, such as Scale, American
Blight, &c. These washes must be used in winter up to February and
March, but not after the flower and leaf buds begin to open.

The following formulae for winter washes are given:

I. Caustic soda (98 per cent) ... ... ... 2 to 2| Ib.

Water 10 gal.

This is made simply by dissolving the caustic soda in the water and
applying hot if possible. Care, however, must be taken of the hands
and face.

II. Iron sulphate ... ... ... ... ... \ Ib.

Quicklime ... ... ... ... ... \

Caustic soda ... ... ... ... ... 2

Water 10 gal.

Paraffin (solar distillate) 5 pt.

In this formula dissolve the iron sulphate in 9 gal. of water; slake the
lime in a little water and make into milk of lime by adding more water.

214 Commercial Gardening

Then add milk of lime to the dissolved iron sulphate, passing through a
hair sieve or piece of sacking to strain off gritty particles. The paraffin
should then be added to the sulphate and lime, and last of all the caustic
soda. The mixture should be well agitated during application, and if
applied hot so much the better.

III. SELF-BOILING LIME-SULPHUR-SODA WASH. Formula:

Lime 3 Ib.

Sulphur (flowers of) 3

Caustic soda 1

Soft soap ... ... ... ... ... ... 1

Water ... 10 gal.

Make the sulphur into a thin paste and pour over the lime; then boil for
a quarter of an hour and keep stirred, and add the caustic soda. Continue
to boil for some time, and then add dissolved soap and full quantity of
water.

IV. FOR APPLE SUCKER AND PLUM APHIS. Formula:

Lime 1-1| cwt.

Waterglass ... ... ... ... ... 5 Ib.

Salt 30-40 Ib.

Water 100 gal.

Slake quicklime slowly, and then mix with water in which the salt hap
been dissolved. Strain through fine sacking, and add dissolved waterglass
which makes wash adhere better. This wash may be used up to the time
of the buds bursting.

6. Copper Sulphate (Bluestone, Blue Vitriol, Blue Copperas). The
purest 98-per-cent copper sulphate should be used, as cheaper brands
contain impurities, chiefly iron sulphate, which may injure the foliage.
One pound to 10 gal. water may be used as a winter wash.

7. Copper Sulphate and Washing Soda (Burgundy Mixture).
Formula:

Copper sulphate (98 per cent) ... ... ... 2 Ib.

Washing soda (pure) ... ... ... ... 2J Ib.

Water 10 gal.

Dissolve copper sulphate in 9 gal. of water in a wooden vessel, and the
washing soda in 1 gal. water. Pour the dissolved soda into the copper
solution, and stir constantly. If blue litmus paper turns red in the solution
add more soda while stirring, until the litmus remains blue. This mixture
is found superior to Bordeaux mixture for spraying Potatoes, and is more
easily prepared and applied.

8. Eau Celeste. This is made by dissolving 2 Ib. copper sulphate in
6 to 8 gal. of water in an earthen or wooden vessel, and then adding 1 qt.
of ammonia and mixing with 50 to 60 gal. water.

Modified " Eau Celeste " is made by dissolving 4 Ib. copper sulphate

Fungicides and Insecticides 215

in 10 to 12 gal. water, and stirring in 5 Ib. of washing soda. Dissolve 1 Ib.
of soda in hot water; then add 3 pt. of ammonia, and dilute to 50 gal. of
water. (See " Arnmoniacal Copper Fungicide ".)

9. Hellebore Powder. This is prepared from the roots of Veratrum
albv/m and V. viride, and is a popular remedy against attacks of leaf-
eating insects and caterpillars. The powder is a poisonous alkaloid, but
loses its property by keeping. Fresh powder, therefore, should be used,
and may be distributed by means of a perforated tin or through a piece
of muslin. If used as a solution (which is the most economical method),
2 Ib. fresh Hellebore powder should be added to 10 gal. water, and well
stirred while spraying.

10. Hydrocyanic Acid Gas. This has already been referred to as a
vaporizer and fumigant at p. 169.

11. Iron Sulphate (Green Vitriol, Ferrous Sulphate). Formula:

Iron sulphate ... ... ... ... ... 40 Ib.

Sulphuric acid ... ... ... ... ... 2

Warm water ... ... ... ... ... 10 gal.

Dissolve crystals of iron sulphate in the water in a wooden vessel, and add
the sulphuric acid, and apply hot and fresh in winter to fruit trees. If
allowed to stand for more than twenty-four hours the salt recrystallizes,
and the solution is then less effectual.

12. Paraffin Emulsion (Petroleum, Kerosene, &c.). Paraffin is used
in a variety of ways, and is effective in keeping off attacks of leaf-miners,
like the Parsnip and Celery Fly, and others, if applied before attack. It
is also useful for aphides, caterpillars, slugs, &c. The following formulae
will be found useful:

I. Paraffin 2 gal.

Soft soap ... ... ... ... ... ... | Ib.

Boiling water ... ... ... ... ... 1 gal.

II. Paraffin 1 pt.

Soft soap 1 qt.

Soft water 2

III. Paraffin 1 gal.

Soft soap 1| Ib.

Water 10 gal.

In all cases dissolve soft soap first, and then add the paraffin and stir well.
A very simple paraffin remedy is to add an eggcupful of paraffin and a
handful of soft soap to a bucket of hot water, and churn well with the
syringe, and apply in a fine spray over foliage.

13. Paraffin Jelly. This is made by boiling 5 gal. of paraffin with
8 Ib. soft soap, and adding 1 pt. of cold water, constantly stirring. When
cool this becomes a jelly, and may be used at the rate of 10 Ib. to 40 gal. of
soft water for aphides, red-spider, &c.

216 Commercial Gardening

14. Paris Green (Emerald Green, French Green, Mitis Green).
This may be had in a powdered or paste (Blundell's) form, the latter being
the better. One ounce to 10 to 25 gal. water is used as an insecticide to
prevent attacks of Codlin Moth, in spring, and other pests. If used too
strong it will burn the leaves. This may be guarded against, however,
by adding to the liquid an equal or double weight of lirne in proportion
to the quantity of Paris Green used. By adding a quantity of whitening
to the solution it will be easy to see where the spray is distributed.

15. Pearl Ash (Potassium Carbonate). This is made by boiling the
ashes of plants with water and evaporating to dryness. It is deliquescent
and very soluble in water. The strength varies from 40 to 85 per cent. It
is used as an insecticide and fungicide, 1 Ib. being sufficient for 10 gal. of
water.

16. Pyrethrum (Dalmatian Insect Powder, Persian Insect Powder).
This powder is obtained by grinding the dried flowerheads of Chrys-
anthemum coccineum and C. cineraricefolium. The powder obtained
from unopened flowerheads is considered better, although more expensive.
The powder is used in various ways: (i) Simply by dusting over plants
affected with aphides, &c.; (ii) as a spray, 2| Ib. powder to 10 gal. hot
water; (iii) as a fumigant, by sprinkling the powder over hot cinders in
a greenhouse; and (iv) mixed with flour in the proportion of 1 part to
10 to 30, and dusted over the foliage.

17. Quassia Chips. These are obtained from Picrcena excelsa. They
should be boiled for two or three hours to extract the bitter principle. An
excellent all-round insecticide is made from 1 Ib. quassia chips, 1 Ib. soft
soap, and 10 gal. water. The quassia chips, after boiling in a gallon or two
of water, should be strained off through muslin or sacking, and mixed with
the dissolved soft soap, making the whole solution up to 10 gal. Trees
in fruit, Cucumbers, &c., should not be sprayed with quassia solution, as
it imparts a bitter flavour.

18. Quicklime applied in the form of a powder is a good remedy
against slugs and snails, and is also a useful soil constituent. In a slaked
form lime is also useful, but two or three applications in succession are
needed to kill slugs and snails. It is used with such fungicides and
insecticides as Bordeaux Mixture, Paris Green, &c.

19. Sodium Cyanide. This is used in connection with hydrocyanic
acid gas for vaporizing greenhouses, as stated above, p. 169.

20. Soft Soap (also known as Whale-oil Soap, Train-oil Soap, Fish-
oil Soap, and Potash Soap). This is one of the cheapest, simplest, and
at the same time most effective insecticides used for horticultural purposes.
Good samples should be free from resin and contain not less than 8 per
cent of potash. It dissolves readily in water, and 1 Ib. to 4 gal. serves to
kill aphides, mealy bug, scale, red-spider, &c. Soft soap is mixed with
various other insecticides and fungicides, as may be seen from the formulae
given above.

21. Sulphide of Potassium or Liver of Sulphur. This has become

Fungicides and Insecticides 217

popular as a fungicide. The sulphide is best kept in well-stoppered bottles,
as it decomposes quickly when exposed to the air. For indoor plants 1 oz.
to 5 gal. water is sufficient, but for outdoor plants 1 oz. to 3 gal. water is
not too strong. A little whitening may be added to show where the spray
falls. It discolours paint and woodwork. By adding a little soft soap
to the fluid it adheres to the foliage better, and if a fine sprayer is used
may be applied hot.

22. Tobacco. This has always supplied an excellent insecticide to
gardeners in the form of washes, fumigants, and vaporizers, the active
principle of which is nicotine. It may be used in the form of powder, like
Hellebore, or as a wash when steeped in hot water, or in a concentrated
form in cakes and liquid. The waste ends of cigars, cigarettes, and tobacco
from pipes may be preserved to make a cheap and effective insecticide.
Three pounds of tobacco, steeped in boiling water and allowed to cool for
six hours, will make 10 gal. of insecticide, which will be improved by the
addition of \ Ib. of soft soap.

23. Winter Washes of Lime and Sulphur. The formulae for these
have been given under Caustic Wash on p. 213.

24. Woburn Wash. This is made as follows:

Sulphate of copper (blue vitriol) or sulphate of iron (copperas) 1| Ib.

Quicklime ... ... ... ... ... ... ... 6 oz.

Paraffin 5 pints

Caustic soda ... ... ... ... ... ... ... 2 Ib.

Water 9^ gal.

Dissolve the sulphate of iron or copper in water by suspending in a bag
a few hours in advance. Put the lime in a jar with water not quite
enough to cover it. When the sulphate is dissolved and the lime slaked,
add a little more water to make the latter into a milk, and then pour in
the sulphate solution. Add the paraffin and churn the mixture with
syringe to produce an emulsion. Then add the caustic soda, which if in
powder should be broken up and dissolved separately before use. The
whole wash should be well mixed, and may be applied in the form of a
fine spray, but care should be taken not to let it drip on the ground or
crops beneath. This wash may be used for most of the pests infesting
the bark and shoots of fruit trees during the autumn and winter.

Horticultural sundriesmen supply numerous brands of patent insecti-
cides and fungicides, such as cyllin, lysol, sodalin, VI and VII fluid, H.
Emulsion, &c., and many cultivators often find it more convenient to
purchase these in a state fit for immediate use, rather than go to the
trouble of compounding their own solutions.

SECTION X
Glasshouse Building

.These notes are intended for the man who, starting in a small way,
finds it necessary to study the expenditure of every penny. Our large
horticultural builders can probably put up a large range of houses at a
price very little higher than the grower can do it for himself; but when
it comes to one or two houses an appreciable saving can be made by doing
the work oneself, and if the builder is a handy man the results will bear
comparison with the professional work. All the timber can be obtained
ready prepared, and the Ventilators and louvre boxes can be got any size
the grower likes. The most difficult part
of the work is getting a good start.

Houses are best built running north
and south for all except the earliest work,
when lean-to's facing south are best. A
start is made by laying out the footings.
A good long garden line is wanted for this
purpose; long enough to go all round the
proposed house will not be amiss. It is
most important to get the corners quite
square. A large square can easily be made
out of two lengths of l-in.-by-3-in. batten, Fig. 104

or the line can be set out square as follows.

Stretch the line along what will be the side of the house. Peg out the
exact length of the house, inside measurement. Use pieces of stiff thick
wire for the pegs, and push them in quite straight and about 18 in. deep,
so that they will not be disturbed when the footings are taken out (see
fig. 164). AF is the line so laid down, and A is one of the corner pegs.
Measure off AB 12 ft., and put in a small thin peg. Measure off AC 16 ft.,
and run a pin through the line at this point. Slip the ring of the tape
measure over the peg B. Now hold the tape at 20 ft, and bring the line
AC to such a position that the 20-ft. mark on the tape comes right on
the pin in the line AC. Then AC will be square with AF. Now the width
of the house can be measured off along AC, and a long peg put in as before.
The performance is repeated at the other end, F, and then the other side

218

I =

I I

8 ^

;

Glasshouse Building 219

line can be laid down between the pegs so found, and the outline of the
house will be complete.

Before proceeding to take out the footings it will be as well to consider
the question of the walls. The simplest and the quickest to put up are
wooden walls, but an efficient wooden wall will cost almost as much as
concrete and will always be a trouble.

However, if wooden walls must be built, the best way to do it is to
get good oak posts, and set their butts in concrete after thoroughly tarring
them. As space is limited, the details of only one form of wall can be
given. Brick walls can be made in 4^ -in. work with 9-in. piers every
6 ft. along the outside, but for strength, durability, cheapness, and ease
of erection the concrete wall takes first place, and so this is the wall chosen
for description.

For this work a quantity of thick plauk and some 3-in.-by-2-in. quarter-
ing will be required. The planks must not be thinner than 1^ in., and
1| in. will be better, though the thinner size will do well enough if it is
well supported. This planking will by no means be wasted, as it can be used
after to make part of a shed, frames, or may simply be kept for wheeling
on till wanted for building again. Enough planking should be got for
about a day and a half's work and to make a platform about 12 ft. square
to mix concrete on. For two men and a boy this would mean about 1400 ft.
run of l^-in.-by-7-in. plank, and about 400 ft. run of 2-in.-by-4-in. scantling.
The quantity would vary a little, according to the size of the house. The
above quantities were used on a house 140 ft. long, and have since helped
to build several more.

A 4-in. wall will be quite thick enough for any ordinary height of
greenhouse wall; a lean-to wall would have to be thicker.

To return to the footings. The four pegs are now in position, marking
the corners of the inside of the house. Lay down the line 6 in. inside
these pegs, and cut all round with a sharp spade. Shift the line outside
the pegs 18 in. away from the line just cut, and cut all round as before.
Now dig out the trench so marked out, one spit deep, putting the earth on
the inner side of the line for use on the borders, or else far enough away
from the outside to allow a barrow to be wheeled along between. Stretch
lines tightly between the four corner pegs, which should have been left
undisturbed, and peg the line down at intervals to make sure it will not
get moved. The 4-in.-by-2-in. scantling is now cut into convenient lengths
for posts, say 4 ft. for a 2-ft.-by-6-in. wall, and a chisel point is made at one
end, making the cuts on the 4-in. side of the wood only. A post is now
set up in each corner just so far inside the lines as to allow the planks to be
used for the concreting to be set up on edge between the line and the post
both ways. Get the posts perfectly upright with a plumb-line, and fix
them so by means of two stays made of slating batten driven into the
ground behind each post, and nailed to it near the top so as to hold it
firm in two directions (see fig. 165). The simplest way to get all the posts
the right distance from the line is to make a plumb-board like fig. 166. The

22O

Commercial Gardening

board is made exactly the width of the wall, plus twice the thickness of
the planking to be used for the concreting: in the case of a 4-in. wall and
1^-in. plank this will be 6J in. At one bottom corner, A, cut out a little
square piece the thickness of the planking, 1 in. Now if the plumb-board
is set up with the point B, as in figure 166, touching the line, the wider part
of the board will overhang the line by the correct amount, and if the posts
are driven in touching this edge they must all come right. When cutting
out the posts it must be remembered that they must be made long enough
to allow for the height of the wall at its highest point, plus the depth of

the footings and 4 or 5 in. to
go into the ground, and about
6 in. extra, so that if the wall
is to be say 2 ft. 6 in. high,

Fig. 165. Corner Post fixed with Stays

Fig. 166. Plumb-board

the posts must be at least 4 ft. high, and if the ground slopes much across
the house, they had better be higher by the amount of the slope, so that
they can be used for both walls.

This point must now be considered. A greenhouse should have a fall
of 6 in. in the 100 ft. This will allow the gutters and pipes to be fixed with
the least amount of trouble. Probably the ground will have more natural
slope than this. The wall is to be 2 ft. 6 in. high, so measure off that
height on the post which is in the lowest corner of the site. This can be
judged near enough by the eye. At this height nail on a small crosspiece
square with the post. About 6 ft. off put up another crosspiece dead level
with the top of the first one and in a line with the footings. Now sight
along the tops of these two crosspieces, and mark off on the post in the
farther corner of the trench where the eye strikes it. This point is level
with the 2-ft.-6-in. mark on the first corner post. Mark off on the farther
post a height of 2 ft. 6 in., as on the first, and see what the difference is

Glasshouse Building

221

Fig. 167. Plumb-level

between the measured mark and the sighted mark. A rise of 6 in. per
100 feet is wanted, so that, supposing the house is to be 100 ft. long, the
measured mark should come 6 in. or more above the sighted mark. Sup-
pose, for the sake of illustration, it comes 9 in. above; this shows that the
ground has a natural rise of 9 in. per 100 feet. Now that the rise of the
ground is ascertained, the building may
be proceeded with. Take the plumb-
board (fig. 166), and against the line
as already described put up a row of
posts, 5 ft. apart, all the way up the
line, and fix them perfectly upright
with a batten stay driven into the
ground on the inside of the house, and

nailed near the top of the post. When these are all upright, stand the
plumb-board up against each one, and drive in another post on the opposite
side, the plumb-board being thus used to give the right distance between
the posts. At the same time join the tops of the posts together with a

short piece of slating batten; one
screw to each post will hold it well.
There is now a double line of posts
all up the trench, perfectly upright,
the right distance apart to take the
boards and the concrete, and tied to-
gether at the top with the batten to
keep them from spreading when the

Fig. 168. Showing Posts at corner of
Building, and Boards arranged for Con-
crete Walls

concrete is put in between the boards. The posts are carried round the
ends of the house at the same time, and a glance at fig. 168 will show the
arrangement of the posts at the corners.

Prepare a number of little pegs about 15 in. long out of l-in.-square
batten, and point their ends; one to every post will be wanted, and two to
the corner posts. Get a contractor's level, which is a piece of board about

222 Commercial Gardening

6 ft. long, with its edges planed parallel and a level set in one edge cor-
rectly. The plumb-level shown in fig. 167 is a very simple thing to make,
and will do the work quite as well as the level just described. Whichever
is used it must be set to the rise of the house in this case 9 in. to the
100 ft. This is done as follows: Place the level on a perfectly level table
or bench. Now raise one end of the level till it has a rise of 9 in. per
100 ft. For a 6-ft. level this will be almost exactly in. j^j- to be
exact. Mark on the level where the bubble comes to, or on the plumb-
level where the plumb-line swings to, and use this mark to work to instead
of the centre mark. Drive a peg into the ground at the bottom of the
lowest inside corner post till it is only about 2^ to 3 in. out of the ground.
Go to the next post and drive in another in a similar position, but while
it is still too far out of the ground test it with the plumb-level placed on
the top of the first peg. Drive the second peg in gently, till, when the
level is resting on the tops of the two pegs, the line stops at the mark
on the level showing the rise of 9 in. per 100 ft. Proceed in the same
way up the line of posts; but the pegs in the end of the house are set
dead level. Now take a small level, or a square, and drive in a peg on
the inside of each of the outside row of posts, getting it perfectly level
with the corresponding peg on the inside post opposite. If there are any
lumps on the ground which bring any of the pegs less than 3 in. out of
the ground, the bottom of the trench must be shaved out with a shovel
till the correct depth is attained. Any hollows are left as they are for
the present. The planks are now put into place between the posts, the
lowest ones resting on the tops of the pegs; thus, whatever height the
wall, as long as the planks used are uniform in width, the top of the wall
is bound to come straight and of the correct rise. The planks are kept
from falling in by standing pieces of wood the width of the finished wall
down between them. The planks being put up as far as they will go, the
mould thus formed, starting from the doorway at one end and up the side
of the house as far as the planks will reach, is ready for the concrete.
Where a doorway is to come a piece of plank is put down between the
boards at the correct spot, set perfectly upright with the plumb-line, and
nailed in place. Make a platform of boards on a level spot near the mould
for mixing concrete on. The concrete may consist of cement mixed with
beach and sand, broken brick rubbish and sand, breeze, broken clinkers and
sand, or, best of all, ground clinker with brick ends put in as the concrete
is put in position. The proportions should be as follows: 5 parts of broken
brick, clinker or beach to 2 parts of sand and 1 of cement. The clinker and
brick rubbish should have all the large pieces broken up with a hammer
till they are no larger than an egg. If on mixing up a small quantity
there does not seem to be enough fine stuff in the mixture, a little more
sand and a little less of the large stuff should be added, and the same with
the beach. The theoretical perfection of concrete is material of some hard
nature broken into pieces that will go through a f-in. sieve, enough sand
to fill the interstices between these pieces, and enough cement to fill in

Glasshouse Building 223

between the grains of sand. When ground clinker is used no sand is
wanted, as the clinker is fine enough; and as this substance forms a very
tough concrete, 8 parts of ground clinker to 1 part of cement will be a
good mixture. When calculating out the quantities, allowance must be
made for shrinkage. Ground clinker will occupy about one- sixth less
space when mixed and put in place than it will when dry, while beach
may be calculated as beach alone, the spaces between the stones taking
up all the sand and cement. The shrinkage of other materials had better
be ascertained by trial of a small quantity before ordering the bulk. The
best way to measure the materials is to make a box of 1^ cub. ft. capacity,
i.e. measuring 1 ft. 6 in. by 1 ft. by 1 ft. Nine of these boxes full makes
just \ cub. yd., and this is a handy quantity to mix up at a time. Of course,
when the proportions are 1 in 8, as for the beach and broken brick, the
quantity is just short of | yd.

If the box is treated as one part, no mistake can be made. The
materials are shot in a heap on the platform and turned over twice dry
to mix them. They are then spread out over the platform and water
added through a fine rose, while Canterbury hoes are raked backwards
and forwards through the mixture till it seems fairly wet. The mass is
then turned up into a lump again, water being added whenever a dry
portion shows, the lump being worked all the time with a Canterbury
hoe as before. If not wet enough then, it must be turned once more. The
finished product should be neither too wet, so as to be sloppy, nor too dry,
so as to be solid. The concrete is wheeled to the mould and shovelled in.
The first layer may be shot off the shovel with some force, so as to make
it spread out beyond the boards, any space that is not so filled being filled
up from outside up to the lower edge of the first board. As the work
proceeds the louvre boxes are put in, well bedded in, and fixed by a couple
of nails lightly driven through the boards. These louvre boxes are made
with the sides projecting beyond the ends, for building into brickwork, &c.,
and for concrete work these projections had better have a V cut in them
and have the concrete worked into the V when they are set in the wall.
As the concrete rises to the top of the planks the plate ties must be put in.
These are simply pieces of flat iron 1 ft. long by 1 in. by \ in. thick, bent at
right angles, with one arm 4 in. and the other 8 in., and a f -in. hole punched
near the end of the longer arm. These are put in at every 10 ft., and
always one at each corner or where a door post will come. They are set
touching the inside boards of the mould, and the hole should be about
1| in. above the top of the wall when the concrete is filled right up. The
top of the wall is best finished off with a builder's trowel, being nicely
smoothed down. The concrete should be left alone for twenty-four hours,
and then the little crosspieces are unscrewed, the posts taken out till the
last few feet of finished wall are reached, and the planks lifted out,
scraped clean, especially along the edges, and placed in position farther
along and filled with concrete as before. When putting the planks in
place it is best to arrange them so that the ends all come in different

224 Commercial Gardening

places, then where two planks meet their ends are made secure by screwing
a piece of wood over the join on to the planks above and below. The
joints in the top and bottom planks have to be made with a short piece
of board put lengthways. When the walls are finished they should be
left to harden while the woodwork is painted and prepared. All the wood
can be bought ready formed, and it only requires the joints to be made,
and the sash bars cut to the right length and angle, to be ready for use.
When ordering, make allowance for the joints and order a few sash bars
extra, for some are sure to be a little short or twisted; these are reserved
for filling in the ends. The bars where the ventilators come can be shorter
than the others, and are supported by the ventilator seat instead of the
ridge. This plan makes a better job of the ventilators and saves a little
wood into the bargain.

All houses are the better for a purlin, even if the bars are short ones
and no purlin supports are used. Many houses 16 ft. wide have no purlin
supports, but the facilities these offer for the supporting of shelves soon
make up for the extra cost. Besides
this, a house built with purlins pro-
perly supported and tied to one another

Fig. 169. Scarf Joint Fig. 170. Half-lap Joint

across the house will be much stronger than the other form and will not
require the iron ties running from the plate to concrete blocks in the
border. These ties are nothing but a nuisance, and a poor substitute for
the purlin ties at the best.

The best joint for the plate, purlin, and ridge is the scarf joint (fig. 169).
It takes a little more wood than the half -lap joint (fig. 170), but is stronger
and easier to make. The latter, however, is used at the corners. To get
the correct angle for the ends of the bars an experiment must be made.
A piece of plate is laid in position on either wall, and a small section of
drip nailed in position on either side; a little piece is also cut off a length
of ridge about 2 in. will do. Two bars are then taken and carefully
fitted until they will occupy their final position with the little piece of
ridge between the upper ends, and fit nicely down on the plate as well.
Care must be taken to keep the bars exactly the same length while fitting.
The cuts can be made almost exactly right the first time if a good large-
scale drawing is prepared first and the bevel gauge set to the angles so
obtained.

W T hen once the correct angles are obtained the rest is easy. A trough
is made to take the finished bar and a saw-cut made through the sides
of the trough at each end of the bar as in a mitre block. The uncut bars
are now ] f ajc} in the trough, one after the other, and the saw, guided by

Glasshouse Building 225

the cuts in the sides of the trough, will cut every bar exactly alike. The
short bars where the ventilators come have only the lower end cut like
this; the upper end is cut to fit the seating.

After all the wood is cut it should be gone over and all the knots
and resinous places be painted with patent knotting, then a good coat
of priming should be given. As soon as dry, the second coat is given,
special attention being given to the joints. The lower side of the plate
should be tarred, but even if the remainder of the plate is ultimately to
be tarred it should be left for a year till thoroughly seasoned: for un-
seasoned wood, tarred, will develop dry rot very quickly.

The end rafters are cut in the same trough as the sash bars, and care
must be taken to cut them in pairs, as they only have a glass rabbet on
one top edge for the roof, and one bottom edge for the ends. The best
way to avoid mistakes is to set them up in pairs and mark their top ends.

In putting up the roof a start is made by putting up two end rafters,
nailing them lightly at the bottom, and leaning the ends together.
Holes should be bored previously for all the nails in the bars and joints,
to avoid splitting the wood. Two trestles tall enough for the builder to
reach the tops of the bars with ease will be required; a strong plank along
the tops will enable the builder to put up several bars without shifting.
A piece of ridge is now lifted up and pushed between the top ends of the
end rafters and held there while an assistant supports the other end of
the ridge with -a couple of sash bars put in position and lightly nailed
in place. The end rafters are now carefully adjusted and nailed fast.
A long piece of wood is then put up and nailed to a peg driven into the
ground in front of the end of the house: the other end of this piece is
nailed to the side of the ridge as soon as the end bars have been got
quite square with the plate. When this strut is fixed the roof will remain
firm while some more bars are put up, or till the rest of the roof is
finished. Two gauges, exactly the width of the glass to be used, are
made out of scroll iron or hard wood, and as each bar is put up these
gauges are put in where the glass will lie to keep the bars the right
distance apart while the nails are being driven. Where the ventilators
come a long gauge will be required, as two bars are left out till the
ventilator seating is in place. These long gauges want making very
carefully or trouble will be met with when the short bars go in. When
the end of the first piece of ridge is reached the supporting bars are
knocked away and a fresh piece of ridge is put up. The assistant holds
up the free end while the builder nails the other to the first piece, and
then gets down and supports the free end with two bars as before. The
purlin is fixed by boring holes right through the sash bars and the purlin
and driving a long wire nail right through and clinching on the inside.
While the roof is being built it is as well to nail long boards right across
the house, from plate to plate, to prevent any strain being thrown on the
plate before the purlin is on and properly tied and supported.

I see that the setting of the plate has been omitted. This is put

VOL I. 15

226 Commercial Gardening

on a good bed of mortar having a little cement mixed with it, spread
evenly along the top of the walls, the plate being well jarred down to
settle it in position. As soon as it is on it is fixed to the wall by means
of the plate ties set in the wall, coach screws being used to hold it. The
drip is then nailed on. In case any of the ties are a little out of the
straight it is as well to sight along the wall before fixing, and see if
any want letting into the plate or keeping away from it by a small
piece of wood. The purlin ties are made out of gas pipe, which can be
obtained very cheap secondhand; any blacksmith can work them up to
shape. The lengths are all -cut right, and then the ends are flattened
out, bent over to fit the slope of the purlin, and a hole punched for a
coach screw at each end; these are screwed down to the purlin at every
10 ft. The purlin standards may be wood, tied down to a concrete
pier at the bottom and screwed to the purlin at the top, or of gas pipe
set in a concrete block at the bottom and split, spread apart, and screwed
to the purlin at the top. The gas pipe is the better material. If used
it is a good thing to slip a 2 -in. drain tile on the lower end before
it is flattened, to make it grip the concrete. While the concrete is being
put round the end the pipe is held up, and when the hole is full enough
it is slipped down till it is bedded on the concrete. Soil is then filled
in all round, and cement is made to a thick cream and poured down
between the pipe and the standard. This arrangement will keep the
standard from rusting where it enters the ground. I have never seen
anyone else do this, but offer the idea for adoption by the man who builds
to last. I always do it myself; it is very cheap and prevents all rusting
through at the ground line. If iron or wooden standards are dispensed
with the house must be kept from spreading by iron rods screwed to
the plate and set in a concrete block in the border; these are put in
every 10 ft. There is very little economy in this method, as unless
the walls are very low, almost as much pipe is required as for standards,
and these plate ties are always in the way.

If the house is to be heated, a stokehole must be dug at the lowest

end of the house. Plenty of room must be allowed for working in front
of the boiler and for a division for fuel. The space for fuel need not be
very wide if a kind of bin is made of boards fitting into grooves made
with pieces of batten fixed to the walls of the hole. Three feet will do
nicely for this division. In front of the boiler a space equal to the length
of the boiler when set, plus 1 ft. extra, should be allowed for withdrawing
the cleaning rods from the flues. The walls of the stokehole are easily
made with concrete. The chimney should not be skimped, but should be
made 15 ft. high, and with a flue at least 1 ft. square; a larger boiler
will want a flue in proportion. A 3-in. drain should be taken from the
bottom of the stokehole, so that no water can collect and the pipes can
be emptied at any time without trouble. If there is a good natural slope
to the ground, and there is some distance to go with the drain, the job
may be made less formidable by gradually bringing the drain nearer

I '

Glasshouse Building 227

the surface, and then it can be carried the rest of the way at a depth
of 18 in. As long as a fall of 6 in. per 100 ft. is allowed, the drain can
be reduced in depth as soon as possible. The stokehole must be made
deep enough for the flow pipes to be taken off the boiler easily. In
this connection a lot of room may be saved if the boiler is fitted with
a short bent flow socket. If more than one house is to be run from the
same boiler, screw-down valves must be provided on the flows and re-
turns in each house. All exposed pipes round the boiler and leading to
the houses should be coated with asbestos cement, and the pipes from
the boiler to the houses are much better boxed right in with brickwork
or concrete. A serious amount of heat will be wasted unless this is
done. The back rows of pipes can be slung from the plate by iron hooks
fixed to the plate with a 2-in.-by-J-in. coach screw. If these hooks are
made all the same length, and the proper fall has been given to the house
walls, the pipes can be set with the greatest ease. For greater security
it is best to have the pipe hooks bent over at the top so as to fit the
plate, and thus give the coach screw assistance in bearing the weight
of the pipes. The front rows of pipes are slung from the purlin standards
or placed on brick or concrete piers. These are very simply made with
concrete as follows: Holes about one spit deep and 1 ft. square are dug
out in a line up the house, where the pipes are to come; pegs are
set up in the middle of the holes and the correct rise given to them
in the same way as to the pegs used when giving the rise to the walls;
2 or 3 in. of concrete is put over the bottom of the holes and then a
little framework of any odd bits of rough wood is put round each peg
so as to leave space for the pier to be made 5 in. square. The concrete
is now filled in up to the top of the pegs and the piers will be ready as
soon as they have set. When the pipes are put on the top they should
be bedded in cement mortar. The pipes are put together with cement
joints made as follows: The pipes are slipped into each other, then about
two strands of pipe yarn are twisted up and driven into the joint with
a caulking tool till the end of the joint is reached. Pipe yarn as bought
consists of four strands twisted, but this is too thick to be driven in.
Three strands are now twisted up and just tucked in all round the joint,
leaving a little hole at the top. Make a little cup with the loose ends
of yarn and pour into the space between the two rings of yarn cement
mixed to a thick cream till no more can be got in. Tuck in the loose
ends and drive the yarn in as far as possible. The next day the joint
can be faced up with neat cement made into a stiff mortar. Nothing
.short of a red heat will loosen such a joint, and they will stand all
ordinary pressures without leaking; a few drops may ooze through when
the pipes are first filled, but this will generally stop in a short time; if
not, the facing must be chipped off, and, if possible, some of the yarn
scraped out and the joint refilled with cement mortar as before. Hot-
water pipes can easily be cut with a sharp cold-chisel to whatever length
is required. The chisel should be given a point with a rather wider

228 Commercial Gardening

angle than is usual, and the temper should be as hard as possible to
stand without chipping. The wide angle helps in this matter. A mark is
made round the pipe where it is to be cut, and the pipe laid on the ground
so that it is touching immediately beneath the cut. The line is now
followed round with the chisel, giving light sharp taps to the tool with
a hammer. As soon as the line is chipped all round, go round again,
hitting a little harder, but still as sharply as possible. During the third
time round the pipe will probably crack all along the mark and break
off clean; if not, the process must be repeated till it does crack. The
flow pipes in the house should stand 6 in. higher than the returns,
and an air pipe must be fitted at the highest point in each row.

A tank for keeping the pipes supplied with water must be placed
somewhere where it can be filled easily. This tank should not be too
small, or when the water in the pipes gets hot the expansion will cause an
overflow and a consequent shortage when the water cools again; 20 gal.
will do for a small house or two, but a 30- or 40-gal. tank will not be
a bit too big for say 1500 ft. of pipe. An expansion pipe must be fitted
to the boiler, and should be 1 in. diameter for anything but a very small
boiler; this pipe should rise to a height of 6 ft. above the highest point
in the pipes. When setting the boiler, a good rise should be given to it.
The makers will say what rise to give their special boiler, but any of the
forms of saddle boiler will want a rise of f in. to the foot.

With regard to water supply, for forcing, it will be necessary to
have tanks in the houses, and for obtaining warm water one of the
pipes should be taken through the walls. To do this a sliding collar
with a joint formed with indiarubber rings must be put on to the pipes
where they will pass through the walls of the tank, and this must be
done before the pipes are joined together. These collars are built into
the walls of the tank, and the pipe inside is thus free to move a little
with the expansion and contraction due to the temperature. If this is
not done the movement will crack the walls of the tank. Tank walls
should be 6 in. thick, made of good concrete, and faced with sharp sand
and cement in the proportions of 1 part cement to 2 parts sand. When
the facing is set it should be brushed over with a wash made of neat
cement, or, better still, let the walls get quite dry and then paint over,
first with a solution of Castile soap, f Ib. to the gallon of water, allow-
ing twenty-four hours for drying, and then with a hot solution of 2 oz.
of alum to the gallon. This process can be repeated if necessary; but
it is said that four coats are impervious to a head of 45 ft. of water, so
that one coat should be sufficient for a greenhouse tank. When ground
clinker is used for making the concrete it may be economized by making
old bricks or the concrete to a batter, and as it is filled into the mould
any kind of hard rubbish can be bedded in it. Long tank walls should
have old lengths of gas pipe put in to strengthen them, and pieces of
small pipe or iron bar should be bent round and set in the corners.
Corner irons should be put in the greenhouse wall as well.

Glasshouse Building 229

To return to the actual building of the house, some form of gearing
should be fitted to the ventilators, and there are several good and cheap
forms on the market; but the bottom gearing is more difficult to do
cheaply, and the only thing to do is to have one worked by levers
fitted to a gas pipe running in bearings screwed to the louvre framing,
the movement being applied by means of a worm wheel and cog.

The glazing can be let out piecework at 2s. Qd. per 200-ft. box of
glass, unless time is no object. Brass brads should be used for fixing
the glass and no top putties. The lowest panes should have three brads
at the bottom edge to make sure they shall not slip down. In some way
or other these bottom brads work out and let the glass slip down; and
the only suggestion I can make is, that the drip, freezing round brads
lifts them out a little at a time till they are quite loose. The best hinge
for ventilators and louvres is that supplied by Messrs. Paine, Main-
waring, & Lephard, of Worthing, whose patent it is. I am not aware
of any other patent makes, and so feel at liberty to mention this form
as better than the common cross garnet or the water - joint T hinges,
which soon wear or rust out. The ventilators can be glazed before
they are hung. Before the glazing is done a couple of wind stays
should be put in at each end of the house; these are made of pieces
of 1 -in.- by -3 -in. batten, the longer the better. These pieces of batten
are carried from the under side of the top end of the rafters to the
plate, as far back in the house as the battens will reach, and a screw
is put through into every bar where they cross; but the glass gauge
should be put in while the stays are being fixed to the bars, to make
sure that they keep the right distance apart. As the end rafters are
1 in. deeper than the glass bars the stays will have to be let in; this
makes all the stronger job.

Allowance must be made for carrying oft' the rainwater from the
roof. A cheap form of gutter can be made of wood. Instead of using
the usual narrow drip, l-in.-by-3-in. batten is nailed in its place, and
to the outer edge of this pieces of l-in.-by-4-in. batten are fixed by
screws placed at every foot. The joints between the ends of the pieces
are made by making a saw-cut right down the middle of each end, and
then when all the pieces are in position short pieces of hoop iron are
driven up the cuts; when the gutter is well tarred there will be no leak.
Outlets can be made into the tanks, and the waste water from the ends
can be carried oft' into a drain.

Where it is important to save all the water it is best to take the
rainwater from the end of the gutter through 2-in. gas. pipe laid under
the border to the first tank; then if the tanks are joined up the water
will fill all at the same time. If iron guttering is preferred, the narrow
drip is used and the gutter fixed to the plate under it. As soon as the
glazing is finished the last coat of paint should be got on, and for inside
work some special greenhouse paint should be used; it may cost a shilling
a gallon more, but it will last much longer. There is also a special

230 Commercial Gardening

greenhouse putty called "Plastine". This is double the cost of ordinary
putty, but it never gets hard, and repairs can be carried out with the
greatest ease; there is also less shrinkage with this, and consequently
less leakage. All ironwork should be coated with iron-oxide paint.

Glass can be got in all sizes, and a very usual size is 20 in. by 16 in.,
and 24 in. by 18 in., the panes being put in lengthways; more bars are
required this way, but the house is stronger. The glass used should
always be 21-oz. [w. M. B.]

Greenhouses on Rails. About twenty years ago the idea of having
movable greenhouses occurred to the Horticultural Travelling Structures
Company, and many of their buildings are now to be seen in actual use by
market growers in all parts of the kingdom. This company has protected
and patented its structures, and are the only builders in the United
Kingdom. Quite recently some American growers have had similar green-
houses built on the same principles. The system consists in having a rail
at each side upon which the greenhouse rests and runs along by means
of wheels when it is necessary to move it from one crop over another.
The Plate shows how the rails are fixed at the sides and between two
houses. The rail in the centre is of rolled steel channel iron, and rests
on iron stanchions bedded in concrete, and serves the purpose of a guttei-
as well as a railway. The outside rails either rest on brickwork or on
stanchions; in the latter case the spaces between the stanchions being
filled in with creosoted boarding.

These travelling glasshouses are used chiefly for bulbs, Strawberries,
and low-growing crops generally, and in cases where a rotation is required
without the application of much heat for forcing purposes. In England
where the houses are in use, three crops of bulbs chiefly Narcissi and
one crop of Tomatoes, are generally produced during the year. In the
Channel Islands, however, four crops of bulbs are often grown one after
the other.

A modified type of glasshouse has recently been brought out by the
same company. It is from 40 to 50 ft. wide, with high sides to the eaves
to allow greater headroom for the crops. Such wide houses are common
in the United States, where the roofs are trussed by rolled rods fitted
together by forgings or screwed together in castings. This wide type of
house is considered superior to the older forms although it is more ex-
pensive to erect. The Horticultural Travelling Structures Company have
substituted substantial wires for the rods used in the American houses,
and this reduces the cost considerably, and the new system, which has been
patented, can be applied to houses 30 ft. wide as well as to those of wider
dimensions.

The other photographs show some of the more generally adopted glass-
houses used by market nurserymen in England. They are from designs
made by Messrs. W. Duncan Tucker & Sons, of Tottenham, who not only
erect them for the trade, but also supply timber already prepared to
growers who prefer to erect their own greenhouses.

SECTION XI
Heating Apparatus

Market growers and nurserymen who have to erect large greenhouses
for their crops do so strictly on business principles. The ornamental
structures seen in private gardens and public establishments do not appeal
in the least to men who have to grow plants for a living, and who erect
glass structures not because they like to, but because they must. Not only
must money bo spent in the erection of glasshouses and frames, but a
suitable temperature must be maintained in them by means of artificial
heating. In the old days, before hot -water pipes came into use, glass-
houses were heated by means of "flues", and in very old gardens some
of these still exist. Flues consist of a passage from the furnace up and
down one side, or all round, a house, and enclosed by tiles or bricks in
such a way that sulphurous fumes shall not leak into the house and
destroy the plants. The heat and smoke are carried along these flues, and
find an exit in the chimney. The heat obtained from the flue surfaces was
much or little according to the way the furnaces were fired, and excellent
results were obtainable by this method of heating.

The flue system, however, is now obsolete, and no one would dream
of heating a modern glass structure by it. Hot- water pipes and boilers
have come to stay, and taking everything into consideration, they not only
supply all the heat required, but they can be regulated by means of valves
to raise or lower the temperature. Not only that, but hot-water pipes can
be arranged wherever the grower wishes either along the floor, around
the walls, under or over the stages or benches, and along the roof itself
if necessary. Indeed in many modern glasshouses in large market nur-
series 4- in. pipes are run along the entire length of a house overhead.
It is claimed for this method of heating that the air throughout the house
is kept at an equable temperature, and in the event of severe frosts no
danger is to be apprehended to plants inside near the glass. The installa-
tion of these pipes overhead naturally entails extra expense, but that is
counterbalanced by the great advantages derived. The pipes are supported
at intervals by Uprights, so that there is no strain upon the roof or sash
bars. Although 4-in. pipes are generally used, 3-in. and 2-in. are also-
employed under special circumstances.

231

232

Commercial Gardening

Fig. 171. Rochford Horizontal Tubular Boiler

Boilers. Of these there are many varieties on the market all sorts,
shapes, and sizes. Some of the older types, like the " wedge ", " coil ",

and " conical ", have
been driven out al-
together, even from
private establish-
ments, having been
superseded by the
" saddle " (of various
designs), the upright
and horizontal "tubu-
lars ", the " Cornish "
or cylinder boiler.
And during recent
years the "sectional"
boilers largely used
on the Continent
and in America have
begun to find a footing amongst British growers.

What the market grower and nurseryman aims at above all things is
to have a boiler that will not only wear well, but will generate the greatest

amount of heat at the least expense
of coal or coke, or labour in stok-
ing. In addition to this, one that
can be repaired easily is a great
advantage.

At the present day perhaps the
horizontal tubular boiler, as shown
in fig. 171, is the most popular with
large growers. The flues are in a
direct line to the smoke shaft, a
greater surface is exposed to the
fire and consequently heat is gener-
ated more quickly; and in the
event of a tube giving way a new
one can be substituted in a very
short time. A boiler of this de-
scription, 9 1 ft. long, is capable of
heating 2000 ft. run of 4-in. pipe,
the total cost for boiler and fittings

Fig. 172. Weeks's Duplex Upright Tubular Boiler being about 20.

The duplex upright tubular

boiler as shown in fig. 172, although extensively used in private places,
is not so largely patronized by big market growers. This particular boiler
is made in two equal parts each of which can be worked independent of
the other in case of accident. As a rule the two sections are worked as

Heating Apparatus

233

Fig. 173." Saddle " Boiler with Waterway End

one boiler, and this gives the advantage of two flows and two returns,
which can be made independent of each other if necessary.

The " saddle " boiler is still very popular amongst all classes of growers,
especially amongst the " smaller "
men who cannot at first, perhaps,
afford to instal the dearer kinds.
The plain "saddle" boiler, which
has an opening right through, still
does serviceable work, but when-
ever possible it is replaced by the
type having a check or waterway
end (fig. ITS). There are many
types of these saddle boilers on the
market, one of the flued type being shown in figs. 174, 175, in elevation
and section. It is known as the Gold Medal boiler, and is made of wrought

iron. The heat from the fire (6) strikes the waterway end (e) before
ascending into the centre flue (c), whence it is deflected into the flues right
and left (d), and then goes over
the top of the boiler. In the
figures the ashpit is shown at a,
the flow pipe at k, the return
pipes at i, the sliding doors for
cleaning out the flues at /, and
the draw-off cocks at g. These
are useful when it is intended to
clear the water out of the boiler.
At I the hollow space is shown
round the boiler to utilize the
heat given off from the surface.
In the improved Cornish or
Trentharn boiler, shown at fig. 176,
we have a circular or cylindrical
type, being a modification of the
Cornish steam boiler. The boiler
consists of wrought-iron cylinders
welded together, and is seated on
two iron chairs or supports as
shown at a a. The front chair
forms the frame for the lower
and upper flue doors, shown at
b b, by means of which the soot
can be easily removed. At the
bottom of the cylinder is a plug . c, which, when unscrewed, allows the
water and all accumulation of dirt in the boiler to escape when necessary.
The two furnace doors are shown, one open, at d, while e is the flow pipe
on top, near the back, and / the return pipe low down at the side towards

Fig. 174. Gold Medal Boiler (elevation)

Fig. 175. Gold Medal Boiler (longitudinal section)

234

Commercial Gardening

Fig. 176. Stevens' Improved Cornish Boiler

the front. In the Cornish or Trentham boiler a large water space is
exposed to the fire, and as the heat has most force on the upper side,
where there is less likelihood of matter accumulating, there is an excellent
circulation of hot water through the flow into the pipes in the houses.
Sectional Boilers.^Of late years these have attracted some attention

among market growers, and many
are now using them. The chief
advantages appear to be that a
boiler can be added to if neces-
sary if more work is required
from it. Each section is indepen-
dent and can be bolted on to the
others or taken awa}^. They are
considered to be very economical
in fuel, they are easy to stoke and
keep clean, and the cost of brick-
work is saved in the setting'-

Being made of cast iron they are less liable to rust than the wrought-
iron boilers are when fixed in a damp stokehole; and in the case of a
section giving way, it can be easily replaced instead of the whole boi lei-
being rendered useless as would be the case with a wrought-iron boiler.
There are several kinds of sectional boilers now on the market, one

of the best known being the
"Robin Hood "of Messrs. Foster
& Pearson (fig. 177), of which
there are several patterns.
Other makes are the " Mona "
and " Anglian ". The illustra-
tion (fig. 178) shows a type
having a Sylphon automatic
regulator by means of which
the draught can be regulated.
Automatic regulators, how-
ever, are not recommended
for damp stokeholes, as the
rust soon causes the working-
parts to be out of repair.

Setting" Boilers. Gene-
rally speaking it will not
pay a nurseryman or market
grower either to set his own
boilers or pipes or to build his
own greenhouses. That is work best done by horticultural builders who
make a speciality of it. And yet many growers take a pride in being
able to build their own glasshouses, and to set their own boilers and
pipes. Then they can blame nobody else if anything goes wrong. The

Fig. 177. Sectional "Robin Hood" Boiler

Heating Apparatus

writer has had some experience in these directions, but he would not
care to proclaim his work as being altogether a model of superb workman-
ship. At the same time it is useful for a grower, and especially one
with limited means, to be able, at a pinch, to build a greenhouse, or set or
repair a boiler. It sometimes happens, usually on a frosty night in the
depth of winter, that a boiler springs a leak, or a pipe crack.s or bursts in
some place. Under these conditions it is no use waiting for the expert to
arrive, while the crops are being frozen or scalded to death, and prompt
measures must be taken. The old boiler may have to be taken out at

Fig. 178. The " Mona " Boiler

once and replaced with a secondhand one on the premises, or a defective
section of piping must be replaced immediately with a sound one. It is
in special circumstances like these that a man who understands how to
set a boiler or replace a pipe is of the greatest value. There is nothing
lost therefore in acquiring a practical and theoretical knowledge of the
art of heating by boiler and pipes.

Principles of Hot-water Circulation. Every grower should know
why the water from the boiler rises and flows upwards through the flow
pipes and comes back again to the boiler by the return pipes. It may be
possible to explain this by means of the accompanying diagram (flg. 179).
Let A represent a boiler with flow pipe at B, return pipe at C, and fire
at D. When heat is applied, some of the water in the boiler absorbs heat
and therefore expands and becomes lighter, and requires more space.

236

Commercial Gardening

The colder water in the return pipe c, being heavier than the heated
water, rushes in at the bottom of the boiler, and thus pushes the warmer
water upwards, and forces it through the flow pipe to fill the space
caused by the flow of water from c to the boiler. The greater the heat
applied the quicker the circulation. Now, as the heated water travels
along the flow pipe B it is gradually losing its heat, and its colder
particles begin to sink to the bottom. It cannot, however, return the
way it came, because it is being pushed forward by the hotter water
coming from the top of the boiler, which m its turn is forced up by the
colder water entering the boiler by the return pipe c at the base. Thus,
while the water in the pipes is gradually losing its heat, that in the

Fig. 179. Diagram showing the Circulation of Hot Water in Greenhouse Pipes

boiler is constantly rising in temperature, and rushes to occupy the space
that is being constantly vacated by the colder water.

If by any chance the water in the flow pipes and in the return pipes
and boiler was of the same temperature, circulation would cease alto-
gether, as when the fire goes out and the water cools. There must there-
fore be a difference in the balance between the hot and cold water to
maintain a regular circulation. In other words, one column of water

must be heavier than the other. This is secured by having the flow and
return pipes at different heights, and the boiler at a lower level than
either. When pipes are being set there is always a very slight rise in
the flow pipe from the boiler to the end of the housCj and a corre-
sponding fall in the return pipe to the boiler. In this way a difference
is secured in the two columns of water. And this difference is accen-
tuated by having water in the supply cistern, which is placed several
feet higher than the highest point of the flow pipe and is connected
with a pipe to the return pipe. This supply cistern should always be
kept filled with water, and as there is a pressure of about | Ib. to every
square inch of its surface for every foot in height, it will be realized at

TREES AND SHRUBS PACKED FOR EXPORT TO AMERICA AT MR. J. SMITH'S NURSERY,

DARLEY DALE, DERBYSHIRE

FORCED LILAC PLANTS GROWN IN POTS FOR EXHIBITION

Heating Apparatus 237

once what force is being exerted to drive the cold water into the boiler at
the base, and the warm water out at the top.

Thus, if a supply cistern is 10 ft. above the base of the boiler, there
will be 5 Ib. pressure to every square inch; and at a height of 30 ft. the
pressure would be 15 Ib. on every square inch. Care must be taken not
to cause too great a strain on the boiler and pipes by having the supply
cistern too high. So long as the cistern is placed a foot or two above the
highest point of the pipes, a good circulation will be secured with a
minimum strain on the apparatus.

To show the enormous strain upon a boiler according to the height
of the supply cistern the following remarks from Mr. W. Jones's work on
Heating by Hot Water may be quoted: "Take a plain saddle boiler with
3-in. water space, and measuring 60 in. long by 21 in. wide by 21 in. high
inside arch, the area or surface of which would be 7368 sq. in. Suppose
the head of water to be 30 ft. above the centre of the boiler, 7368 x 13'02
will give 95,931 Ib., or nearly 43 tons pressure inside the boiler, whereas
the actual weight of water in the boiler would not exceed 3 cwt. If you
increase the head of water to a height of 60 ft. the pressure will be about
86 tons. If you lower it to 15 ft. it will be about 21 J tons, although the
weight of water may remain the same in each case."

The system of hot-water heating for glasshouses is known as the " low-
pressure" system, to distinguish it from the high -pressure system by
which water is brought to boiling-point. Good growers never like their
pipes to get so hot that they cannot bear the hand on them. When this
is the case it indicates either bad and wasteful stoking or that the boiler
is too powerful for the quantity of piping attached. Great heat in the
pipes is injurious to plant life. It makes the atmosphere too dry, and
when water is applied the house is filled with steam from the hot pipes
for a time. A genial heat in the pipes is therefore most desirable.

It sometimes happens, however, more especially in very cold weather,
that the fires must be " driven" to maintain the requisite temperature. Then
the water is heated so much that it flows over from the supply cistern
by sheer expansion. When the water cools it naturally takes up less
space than before, the supply cistern becomes empty, and air enters the
pipes to fill the vacuum caused by the lost water. The air must be got
out of the pipes, otherwise the water could not enter in again. This is
secured by means of an air pipe F, fixed at the highest point of the flow,
and in many cases carried outside the house. Sometimes stopcocks are
placed at the top of the flow pipes, and are examined regularly to allow
the air to escape. In any case these air pipes are necessary, because, owing
to the natural leakage of water by evaporation, air enters the pipes. If
not expelled or allowed to escape, not only would the circulation of the
water be impeded or stopped, but with great pressure the pipes or even
the boiler might burst.

Quantity of Piping- Required. The following table, taken from
Hood's work on hot-water heating, may be given as showing the length

2 3 8

Commercial Gardening

of 4-in. piping required to heat 1000 cub. ft. of air per minute from
45 to 90 F., the temperature of the pipes being 200 F.

Tempera-
ture of
External

Temperature at which the House is to be kept.

Air.

Number of Feet of 4-in. Pipe,

126

150

174

200

229

259

292

328

367

409

112

135

160

187

216

247

281

318

358

75-

120

145

173

202

234

269

307

112

137

164

193

225

259

296

104

129

157

187

220

255

112

140

171

204

If a house containing 10,000 cub. ft. of air is to be kept at a tempera-
ture of 70 F., the external air being at 32 (freezing-point), the amount of
piping required is found thus: Go down the column under 70 and find
the figures opposite the given temperature of the external air, that is 32.
The figures 164 stand opposite this and beneath the 70. Multiply 164
~by 10, and the result 1640 represents the number of feet of 4-in piping-
according to Hood's method. This, however, will scarcely do for horti-
cultural purposes, as no one would dream of heating his hot-water pipes
up to 200 F. only twelve degrees below boiling-point. And, moreover,
the length of piping cannot be varied at will, in accordance with the
fluctuations of the external air. The quantity of piping is really regulated
according to whether a structure is to be treated as a greenhouse or a
hothouse, the latter requiring about twice as much piping as the former.
Taking a house 100 ft. long, 12 ft. wide, and 8 ft. high to the ridge board
with walls to the eaves 3 ft. high, we get a house with about 9000 ft.
cubic capacity. If used as a greenhouse with a minimum winter tempera-
ture of 45 F., about 500 ft. of 4-in. piping will be sufficient in the usual
way, but an extra 200 ft., making 700 ft. altogether, would maintain a
temperature at a minimum of 50 to 55. In a similar house, 1000 to
1200 ft. of 4-in. piping would maintain a stove temperature during the
winter months without heating the pipes to more than 100 F.

Heating horticultural structures by steam is practised in America,
where climatic conditions are different, but it is not likely to be adopted
in Britain.

Fuel. This is one of the greatest expenses to the commercial grower
with extensive ranges of glass, and prices of coal and coke have increased
enormously during the past twenty years, while the price of produce has
fallen just as much; and labour has also increased. The two principal
fuels used are coke and anthracite coal some growers preferring one, some
another. The prices vary according to circumstances, depending upon
proximity or the reverse to supplies, freight charges, carriage, &c. The
average price for coal and coke may be given as 20s. per ton, and a house

Heating Apparatus 239

of 9000 ft. capacity, as mentioned above, will require from i to J ton
per week if kept cool, or about 1 ton if treated as a stove. In the
near future, perhaps, when science will have shown -us how to make
petroleum into a solid commercial article for heating purposes, there may
be good times yet in store for the grower under glass. In the meantime
he must pay the price asked for coal and coke, and see that he engages
intelligent stokers to attend to his fires. A good stoker at 80s. per week
is better than two bad stokers at 20s. each per week. [j. w.]

THIS BOOK IS DUE ON THE LAST DATE
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AN INITIAL FINE OF 25 CENTS

WILL BE ASSESSED FOR FAILURE TO RETURN
THIS BOOK ON THE DATE DUE. THE PENALTY
WILL INCREASE TO SO CENTS ON THE FOURTH
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UNIVERSITY OF CALIFORNIA LIBRARY

KEY TO THE MODEL OF A POTATO PLANT

SECTION I. GENERAL VIEW
Number references as for Section V below

SECTION II. EPIDERMIS OF THE PLANT

1. Flower.

2. Fruit.

3. Diseased Leaf.

4. Healthy Leaf.

(a) Midrib.

(6) Vein.

5. Stem.

6. Healthy Tuber.

7. Diseased Tuber.

8. 9, Roots.

SECTION III. ASSIMILATION

Number references as for Section II above

(a) Denotes Inorganic Materials. (b) Denotes Organic Materials.

SECTION IV. THE FLOW OF SAP

Number references as for Section II above

(a) Denotes Inorganic Sap. (b} Denotes Organic Sap.

SECTION V

1. Flower (reduced).

2. Flower (natural size).

3. Calyx.

4. Corolla.

5. Stamens.

6. Style with Stigma.

7. Ovary.

8. Pollen Passage.

9. Petals.

10. Fruit (reduced).

1 1. Fruit (natural size).

12. Seeds.

13. Stem.

14. Roots.

15. Healthy Leaf (Upper Surface).

16. Epidermis of Leaf.

17. Palisade Cells with Chlorophyll

Granules (very highly magnified).

1 8. Leaf Vein with Sieve Tubes (very

highly magnified).
19 Spongy Parenchyma (very highly

magnified).
20. Stomata.

21. Diseased Leaf (Upper Surface).

22. Epidermis destroyed by Fungi (very

highly magnified).

23. 24, Palisade Cells and Spongy Paren-

chyma destroyed by Fungi (very
highly magnified).

25. Stomata.

26. The Potato Disease (Section of the

Leaf).

27. Healthy Tuber.

28. Eyes.

29. Skin.

30. Starch Grains coloured blue by Iodine

(very highly magnified).

31. Section with Cellulose Threads.

32. Back View of Healthy Tuber.

33. Diseased Tuber with Fungus Growths.

34. Destruction of Skin by Fungi.

35. Destruction of Starch Grains by Fungi.

36. Destruction of Cellulose Threads by

Fungi.

37. Back View of Diseased Tuber.

THE GRESHAM PUBLISHING CO., LONDON

14693.

THE GRESHAM PUBLISHING CO., LONDON