AGRIC, DEPT, 
 
 ENTOMOLOGY 
 
 I IRPflRY 
 

 
 SCALE INSECTS 
 
 ON 
 
 DECIDUOUS AND ORNAMENTAL TREES. 
 
 S. F. CHAPIN, M. D. 
 
 \\ 
 
 Vice-President of State Board ,>/' Horticultural Commissioners 
 
 A REPORT TO THE STATE BOARD OF HORTICULTURAL COMMISSIONERS. 
 
 [Reprinted for the- Author from the PACIFIC Hi \\\\. I'KKSS 
 of <K;t. aSiin.l Nov. 4, 1882.] 
 
 Pacific Rural ''J^ess P. 
 1882. 
 
 it, Sim J-rii 
 
AGRIC. DEPT. 
 
 s 
 
 
SCALE INSECTS ON DECIDUOUS AND ORNAMENTAL TREES. 
 
 By S F. CHAPIN, M. D., 
 
 \', -/Y< xitli'n.t uj til ai<'.. Hoard of Horticultural Commissioner 8. 
 
 A Report to the State Board of Horticultural Commissioners. 
 
 ^Reprinted for the Aiithor from the PACIFIC RURAL PRESS of Oct. 28 and Nov. 4, 1882.] 
 
 The prevalence of scale insects in the or- 
 chards of Santa Clara valley during the past 
 few years has afforded ample scope for their 
 study, to which I have, for the past three sea- 
 sons, devoted what time I could command. 
 Assigned to this work by you, I shall report as 
 concisely as possible the information gained and 
 the results obtained by numerous experiments 
 carried on and observed for two seasons. I 
 shall here use in this paper as a part of it, a re- 
 port presented to the Santa Clara County Hor- 
 ticultural Society, August 6, 1881, by Mr. D. 
 C. Vestal and myself, with such revision and 
 correction as another year has shown to be 
 needed, and with added memoranda to the ex- 
 periments detailed, in order to present their 
 full effects after a lapse of more than a year. I 
 shall also detail other experiments,and shall re- 
 fer to work done on an extensive scale for the 
 destruction of the scale pests, and which has 
 shown most gratifying result.-. 
 
 All scale insects impair, to a greater or less 
 degree, the vitality and productiveness of the 
 tree or plant upon which they live. Of the 
 seven species which have here been observed as 
 infecting our deciduous orchard trees and fruits, 
 five are of frequency and of such importance as 
 to attract the attention of orchardists. These 
 are the Lecanium Olecz, Aspidiotus Rapax, 
 Aspidiotus Conchiformis, Aspidiotus Pernic- 
 iousus and the Icerya Purchasi, the two last 
 named being the most dangerous of all scale 
 pests which the orchardist has to encounter. 
 
 Lecanium Oltte. This scale is beginning to 
 attack other trees than the orange and its kin- 
 dred. A year since I examined an orchard 
 where it existed in overwhelming numbers 
 upon the German prune, Brigg's Hed May and 
 the Early Crawford peaches, upon the Moor- 
 park apricot trees, and most of all upon the 
 Petite prune d'agen trees. This is believed to be 
 the direct result of planting a few orange trees 
 close by. Mr. Ellwood Cooper has written 
 fully upon this scale, and to whose reports I 
 refer you. 
 
 Aspidiotus Rapax. So named by Prof. J. H. 
 Com stock. This scale is rapidly spreading, and 
 is now found in many places where unknown 
 a year or two ago. It seems to be most 
 
 337 
 
 nent in Santa Cruz county, where it can be 
 abundantly found. I have, during the past two 
 seasons, observed it in many places in Santa 
 Clara county, and have had specimens sent me 
 from San Lorenzo, Alameda county, where it 
 was abundant upon pear trees, a branch sent 
 being well covered with the old scale, and also 
 newly hatched young crawling about. 
 
 This scale seems to be native to the willow 
 and alder and other indigenous trees. It, how* 
 ever, is found in great numbers upon acacia 
 trees, upon the black locust and poplar, and 
 upon some of our orchard trees, as the pear and 
 apple. This scale somewhat resembles the 
 Aspidiotus perniciosus, and by many is con- 
 founded with it, but it is not to be compared to 
 the latter for destructiveness. 
 
 Aspidiotus Conchiformis. The one longest 
 known, and which was discovered and described 
 in Maine in 1794, has ever since that time in- 
 fested the apple tree particularly, although 
 found upon other fruit trees and upon the cur- 
 rant. This is now found in great numbers upon 
 almost all old apple trees on this coast, and is 
 commonly known as the bark louse or the 
 oyster- shell scale. It may be found described 
 in works on entomology. This species has not 
 caused so much injury as to alarm fruit grow- 
 ers to any great extent, although it is described 
 by Dr. Packard as doing more injury to the 
 apple tree than any other insect known. 
 
 Cottony Cushion Scale. 
 
 Next will be described a comparatively new 
 scale heretofore, but one which has within the 
 last two or three years been ravaging many lo- 
 calities in widely different parts of the State. 
 This is the so-called dorthesia, or, as named by 
 Maskell, Icerya Purclmsi, and called by Mr. 
 Matthew Cooke the cottony cushion scale. 
 
 This scale has been, it is asserted, known to 
 be on the acacia for seven years in San Jose, but 
 it is only during the past and present seasons 
 that it has attracted attention. Its great pro- 
 litiouess and its destructive abilities have called 
 widespread attention to it. This pest attacks 
 everything in the way of tree, vine or shrub; 
 all the evergreens as well as deciduous trees 
 llhatifatt in its way are attacked, and every orna- 
 
mental shrub on the lawns of souie portion of 
 our cities will show its* presence. The ivy, even, 
 is not. prQof .against ?,t. In San Kfael, San 
 Mateo\ Sruifcu Errbaru aad Los Angelas it is well 
 established. While in San Jose it has not this 
 season caused so great damage as last, yet in the 
 citrus-growing regions it is becoming one of the 
 most serious pests they have to encounter, and 
 it is even stated that, should its ravages not be 
 
 Larvse 
 
 On the Twig. 
 
 Cottony Cushion Scale Icerya Purchasi 
 
 checked, orange and lemon culture will have to 
 be abandoned. 
 
 From the rapid destruction which follows the 
 presence of this scale, it is well that it should 
 be widely recognized, and its first invasion no- 
 ticed and checked. In San Jose, in 1881, it was 
 first noticed in May as the fully developed fe- 
 male, from which the first brood of young then 
 appeared. 
 
 Scale on Fruit and Twig. 
 
 haps the twenty-fifth of an inch in length. The 
 body is pale red; the six legs and two antennae 
 are black. The antenna- are long and club- 
 shaped, and have from six to nine joints, as 
 they are further matured. The antennas are 
 covered with long hairs, which bristle forth 
 prominently. The eyes are small and black. 
 Between the pair of forelegs on the under side 
 of the body is to be seen the beak or sucker, by 
 which the insect secures its nourishment. 
 
 The females partly grown are of a variety of 
 colors, orange red mostly, and spotted over 
 with white and green; some are nearly entirely 
 a dirty white, and many are a pea green. It 
 seems that the coloring matter of the plant they 
 are upon colors them to some extent. Their 
 body is ovoid and elongated and flattened, the 
 back being ridged up with several segments 
 quite prominent. Around the rim of the body 
 are a multitude of hairs, standing out promin- 
 ently. Around the rear half of the body on its 
 rim are a row of tubercles or spinarets, from 
 which a white secretion issues, forming a cot- 
 tony cord, and these placed side by side and the 
 interspace filled up by the same material run- 
 ning lengthwise the body and projecting from 
 it, gives the whole a ribbed, satin-like appear- 
 ance whitish in color. Gradually as the insect 
 matures these projecting ridges approach each 
 other at the ends, and are joined together and 
 curved under slightly at the point, while the 
 sides are at the same time curved under the 
 whole length, and the edges joined together like 
 a flat ribbon- like band, the whole forming, when 
 complete, a soft elastic white sack, the size, 
 and somewhat the shape of a medium sized 
 white bean. The length, when mature, is about 
 three-eighths of an inch; the width one-fifth of 
 an inch. 
 
 Inside the sack are deposited the eggs of the 
 female, among the interstices of a ma^s of cot- 
 
 Ferrmla. 
 
 Male 
 
 Larva- 
 
 SAN JOSE SCALE INSECT-Aspidiotus Perniciosus. 
 
 This present season of 1882 the first young 
 appeared May 25th, the mother insect having 
 gradually matured her eggs from the opening of 
 spring until the young were hatched. The egg 
 of the Icerya is small, pale or orange red, 
 elongated and ovoid. The young just hatched 
 out are very active, and are very minute, per- 
 
 ton-like fiber, which under a high magnifying 
 power is shown to be round, and not more than 
 one-sixth part the thickness of pure cotton 
 fiber, with which it was compared in the same 
 field. This mass of cottony fiber is filled with 
 a great amount of granular matter, for the 
 purpose, it may be, of affording sustenance to 
 
the young insects within the sack. The young 
 hatch out in this sack, and make their way out 
 into the world through a rent in the soft and 
 tender underside of the sack. 
 
 The female, after finding her home and dur- 
 ing maturity, does not move, although she does 
 not lose her legs, but clings tenaciously with 
 her feet to her support, leaving the body tipped 
 up in the rear and the cottony mass movable in 
 any direction. The male insect was only found 
 during a period of about two weeks from Sept. 
 
 On the Twigf. 
 
 grown and with the young hatched out and 
 crawling in the same sack. In 1881 they rap- 
 idly increased from about the first of August, 
 and were continually appearing, and still hatch- 
 ing out in December. 
 
 Every female, it is estimated, produces from 
 200 to 500 young. The young will mature and 
 produce a new brood in about three months. 
 Where this scale infests deciduous trees it 
 may be readily destroyed by the application 
 now found to be successful in treating the Aspi- 
 
 Larvee. 
 
 BLACK SCALE -Lecanium Oleee. 
 
 25tb. This was the observation of 1881, when 
 I found them in great numbers. I have failed 
 to find the male insect this season. It has a 
 long red body, six legs and one pair of very long, 
 dark and transparent wings, prominent eyes and 
 antenme very long and covered with hairs, ar- 
 ranged very much as the feathers of a peacock. 
 The antennae are 16 or 17 jointed. The 
 winged male is easily seen and easily caught, as 
 it moves slowly about, and is not readily dis- 
 turbed so as to fly away. The female insect 
 lives upon the trunk of the tree and large 
 
 diotus Perniciosus, and detailed further on in 
 this report. 
 
 Where, however, evergreens are involved it 
 is a far more serious problem. The best treat- 
 ment for the Icerya, so far found, is that used 
 I by Mr. Cooper, of a strong and hot infusion of 
 j tobacco, applied by spray as near as may be at 
 ! 130. 
 
 Aspidiotus Perniciosus. 
 
 By far the most injurious scale pest infesting 
 j our orchard trees and fruit is the new species of 
 ! Aspidiotus, which, so far as known, originated 
 
 TBCE OYSTER SHELL BARK LOUSE Aspidiotus Conchiformis. 
 
 limbs and down to the smallest twigs, 
 around which it may be seen clinging in clus- 
 ters sufficiently great to completely hide the 
 branch; aleo upon the leaf, along the stem and 
 ribs of which it is fixed, both above and below, 
 although more abundant on the underside of the 
 leaf. 
 
 There are three broods of this insect in the 
 season ; the first appearing in May, the second 
 in August and the third in October, or about 
 three months apart. I have just observed, Oc- 
 tober 15tb, the mature female with eggs fully 
 
 in San Jose, and for some years was confined to 
 this locality. It has been known as the San 
 Jose small, round, black scale and named by 
 Prof, foinstock Aspidiotus perniciosus. The 
 spread of this scale over the State has been 
 gradually taking place, until now it can be 
 found in a number of the fruit-growing counties, 
 notably San Joaquin, El Dorado, Nevada, 
 Placer, Sacramento, Yolo, Solano, Sonoma, Ala- 
 meda, Santa Cruz, San Benito and others, and 
 I am told even in Humboldt in the north and in 
 the southern counties. This scale produces ter- 
 
rible results in an orchard when once estab- 
 lished. Its ravages have caused widespread 
 alarm, and unless checked soon causes entire 
 destruction of the trees infested. The trees be- 
 come entirely covered with the scale, so that no 
 portion of the bark can be seen. The fruit also 
 becomes covered in the same manner and is ren- 
 dered unfit for use. The losses caused by the 
 ravages of this insect cannot be easily computed. 
 Whole orchards are literally destroyed by it. 
 In many cases those who have recognized its 
 presence and destructive power in time have 
 made most strenuous efforts to stay its spread 
 and save their trees, but it has hitherto been, to 
 a great degree, discouraging, owing to the diffi 
 culties encountered in fighting an unknown foe. 
 Within the past two years, however, great 
 progress has been made in destroying this in- 
 flect, and it is now considered certain that we 
 have an efficient means of ridding ourselves of 
 one of the most dangerous pests known to fruit 
 growers. 
 
 The trees attacked embrace every kind of 
 deciduous fruit trees except the Black Tarta- 
 rian cherry, and it is supposed two or three 
 other black cherries. Some varieties are less 
 liable than others to its attacks, but we have 
 found it upon all other trees than those ex- 
 cepted above. 
 
 Poplar and other ornamental and shade trees 
 give it a support. It infests hedges of Osage 
 orange and the wild cherry, many of which 
 have been destroyed in the past two years, and 
 have been dug out. It is found on the currant, 
 and quickly destroys the bush. It has been 
 found upon rhubard, and tomato plants growing 
 in orchards among infested trees. This scale 
 evidently prefers some varieties of trees, but 
 yet, when placed upon others not so well liked, 
 will stay and colonize to some extent. 
 
 The effect of this scale insect upon the 
 tree is peculiar. After a short residence 
 there, the green layer of the bark be- 
 comes stained a very dark red color, which 
 continues until the death of the limb or 
 f ree unless the insect be killed. The bark may 
 then be restored to its normal color and health. 
 
 A Financial Aspect. 
 
 The damage in Santa Clara county has already 
 become so great as to cause the most serious 
 losses not alone to the fruit growers, but also to 
 the public at large and from the orchards ef- 
 fected has greatly lessened the revenue which 
 lias been derived from the production 
 and sale of fruit. One instance stated defi- 
 nitely will suffice to show these losses. 
 
 This orchardist states (1881) that he has 2,000 
 trees badly infested with scale;. 1,000 of these 
 trees are totally destroyed, and will be dug out 
 ibis season; the balance are badly injured, but 
 can probably be saved. This portion of his or- 
 chard in health returned at least $5,000 per 
 year. His loss on crop from these trees in 1880 
 \vas over $2,000. For 1881 there was a total 
 loss of crop on 1,500 trees. This orchard has 
 regularly paid an interest of 10% on $1,000 per 
 "ere. The scale pest alone has cost a loss of 
 820,000 to the owners. 
 
 Further on reference will again l>e made to 
 this orchard. The Assessor's roll for 1881 re- 
 ports in this county 335,537 bearing trees of the 
 apple, pear, plum and peach. This does not 
 
 include the large number of trees which have 
 been destroyed and are unfruitful; neither the 
 immense number of young trees that have been 
 planted, but not yet paying; and, as observed, 
 it leaves out the large number of other varie- 
 ties, cherries, a] moms, apricots, etc., in bearing, 
 which, it is estimated, would make a grand 
 total of 1,000,000 trees. Should the losses ex- 
 perienced by the orchardists now suffering be 
 carried out to all, you can readily estimate the 
 astounding result. The value of the Santa 
 Clara county fruit crop for 1880 was returned 
 at $976,475, notwithstanding the immense 
 losses incurred. The sworn statement of the 
 Assessor, now before rne, says "That all fruit 
 trees in Santa Clara county are assessed as im- 
 provements at the following prices: Trees in 
 full bearing, free from scale, $1.50 per tree; 
 trees bearing, affected with scale, from .00 to 
 50 cts. per tree, and that there is a large num- 
 ber of orchards situated east and northeast from 
 the city of San Jose, badly infested with scale 
 (and after naming some, say?), and in conse- 
 quence are assessed at .00 to 50 cts. per tree." 
 From this it will be seen that the revenue de- 
 rived from taxation is seriously affected by the 
 presence of this pest upon our orchard trees. 
 
 The Assessor's roll for 1882 gi^es of the four 
 varieties of trees named above apples, peaches, 
 pears and plums bearing trees subject to tax- 
 ation 280,347, a deduction from the previous 
 year's assessment of 55,190 trees. This loss is in 
 fact upon apple, plum and peach trees, as the 
 young pear trees coming into bearing, and be- 
 ing assessed for the first time, more than equal 
 the loss on that variety. So it is seen that the 
 loss in assessed value on these three kinds of 
 trees totally destroyed has amounted in the one 
 year to $82,785. This is actually but a small 
 part of the loss, as other varieties of trees des- 
 troyed, and the losses of previous years from 
 the scale as well as the reduced value of trees 
 affected but still bearing, cannot well be enu- 
 merated. These trees were destroyed before 
 the application of proper remedies; now, how- 
 ever, from the knowledge of correct treatment, 
 these losses will soon cease, and the taxable 
 property of the county be immensely in- 
 creased. I feel assured that the next assess- 
 ment will show a decided improvement. Thus 
 the magnitude of this evil becomes apparent, 
 and the problem to be solved is of vast impor- 
 tance. 
 
 Description of this Pest. 
 From the study we have given to this scale 
 during the past three years it may be briefly 
 described as follows: The scale insect is massed 
 upon the bark of the tree and fruit as well, the 
 scale of a dark gray or blackish and tough ma- 
 terial which covers the insect being very small 
 and round in shape over the female, while that 
 covering the male is much smaller and elongated 
 on one side. In both, the higher and central 
 portion of the scale has a yellowish color, and 
 directly under which may be found the insect 
 itself, which is soft and delicate in structure 
 and of a pale straw color. There is no con- 
 nection between the cover and the insect, which 
 is merely protected by it from harm. The shell- 
 I like scale is formed by either the cast-off skins 
 i of the larva or by a waxy secretion of the body 
 j of the insect. The microscope shows the young 
 i female insect oval in shape and flattened. At 
 
first it is very small and hardly perceptible to 
 the naked eye, but careful observation will de- 
 tect it as a minute yellow dot on the bark of 
 the tree, crawling about with the six legs with 
 which it is provided, and seeking a favorable 
 locality upon which to fix itself for life. It 
 will crawl about for only a day or two, and then 
 fastens itself to the bark by a beak-like pro- 
 tuberance which it inserts, and procures nour- 
 ishment from juices of the tree. Immediately 
 upon fixing itself it begins to be covered with 
 a silvery material, which, as it grows older, is 
 gradually changed in color to a very dark hue, 
 and enlarges to the size of about one-sixteenth 
 of an inch in dia.neter. The insect soon after 
 fixing itself loses its legs and antennce, and thus 
 remains through life, keeping its flattened shape 
 but growing wrinkled and almost round, gradu- 
 ally increasing in size to perhaps one-sixteenth 
 of an inch in width and one-fifteenth of an inch 
 in length when full of young. After the young 
 emerge it is dried up and disappears. We have 
 counted from the female, when full of young, be- 
 tween 50 and 60 of the minute sacks which con- 
 tain the young perfectly formed insects ready 
 to crawl about. The young male insect is pro- 
 duced in the same manner and at the same time, 
 though not in such numbers; perhaps half a 
 dozen males to a hundred females. In size the 
 male is about one -third that of the female, and 
 in shape very different, being elongated and 
 more angular, provided with six legs placed 
 differently up on the body, with two antennae 
 and two eyes, and with a teat-like protuberance 
 at the rear end of the body ending with a point. 
 
 At this stage of its existence the male has no 
 wings, and it cannot be discerned without the 
 aid of a magnifying glass. The color of the 
 young male is not a yellow, but of a steej-like 
 or whitish hue It crawls about and fixes it- 
 self upon the bark, as does the young female, 
 and becomes covered with a scale in the same 
 manner, but which is elongated upon one 
 side, and not more than one-half the 
 size of the scale of the female. The male, 
 after remaining its allotted tim'e in the pupa 
 state, emerges as a fully developed insect, 
 having eyes, antenne, six legs and one pair of 
 very long wings of a reddish and transparent 
 appearance, and the protuberance at the rear 
 end of the body is developed into a very long 
 tapering point, nearly as long as the body it- 
 self. The perfect winged male is so minute it 
 can with great difficulty be discerned by the 
 naked eye, crawling and flying about in search 
 of the female, which it impregnates under the 
 scale and then, having fulfilled its mission, it 
 dies. 
 
 In the season of 1880 we saw the winged 
 males first appear on March 23 i, and in great 
 numbers for a few days. The first brood of 
 young scales appeared the latter part of April. 
 Oa June 27th we found the males from the first 
 brood under the scales and nearly developed 
 with appendages and wing pads, and on July 
 2d large numbers of them flying about; also as 
 late as July 25fch, and still later, on August 
 2d, a few were seen. On July 23d the trees 
 were covered with the young of the second 
 brood; August 2d the young males of the 
 second brood were found crawling about. 
 Bark scraped clean on the 23d of July was 
 found on the 25th alive with young insects, and 
 
 some of them already commencing to be 
 covered with scale. As it was expected at the 
 time these observations were made, a third 
 brood would appear about October, so we found 
 it. On October 17th we found the male scale 
 insect in the first pupa stage of development in 
 the winged form, and also on the same day 
 found the perfect winged insect of the third 
 brood moving about on the tree. 
 
 These facts prove conclusively that there are 
 three distinct broods of these insects in the sea- 
 son, the earliest portion of the first brood about 
 March 23d, of the second brood about July 2d, 
 and of the third brood about October 17th, there 
 being apparently an interval of 14 to 15 weeks 
 between the different broods of the season. The 
 young female insects were found crawling about 
 through the season and as late as the last of 
 November. The last brood remains through the 
 winter under the scale until the approach of 
 warm weather in the spring, when they again ap- 
 pear. 
 
 While the Aspidiotus Conchiformis will de- 
 velop but one or at most two broods per season, 
 this new species of Aspidiotus will produce three 
 broods, and each female probably 50 young. 
 This present season of 1882 has been in the de- 
 velopment of fruit and insects about three weeks 
 or more later, consequently the appearance of 
 the scale was not expected as early as last year. 
 The first winged male scale insects of this 
 species were discovered this year on April 25fch 
 crawling about on an English hawthorn tree. 
 At that time no young female scale insects were 
 to be found, but the old females under the scales 
 were approaching maturity, and in due time the 
 young appeared. 
 
 Foes of Scale Insects. 
 
 The natural enemies of the scale insect are 
 the larvae of some varieties of the Coccinellidce, 
 or lady-birds. 
 
 The season of 1881 developed in great num- 
 bers an important enemy of the scale, viz. : the 
 Chrysopa or lace-winged fly, the larvae of which 
 prey upon it. This is a beautiful, slender and 
 delicate fly, bright green in color, with large 
 golden eyes, and very long wings like lace. 
 The eggs are very minute, white and oval in 
 shape, and are attached by a long and slender 
 pedicle to the underside of leaves or the fruit. 
 The larva is about one- quarter of an inch long, 
 slender, and tapering from the middle toward 
 both ends. It is provided with jaws, each per- 
 forated, through which it sucks the juice of its 
 victim. 
 
 Remedies for Scale Insects. 
 
 In 1881 Mr. J. H. M. Townsend, of the Santa 
 Clara County Horticultural Society, kindly 
 placed at our disposal a large number of trees 
 infested with scale for the use of the committee 
 in making such experiments as were desired. 
 A series of careful experiments for the destruc- 
 tion of the scale pest were made and the results 
 carefully noted. "Other experiments had been 
 under way in our own orchards for many 
 months. 
 
 These exprimenta demonstrated on one hand 
 the inefficiency of many applications, and on 
 the other hand showed a certain means for the 
 destruction of the scale insect. The remedies 
 which have proven successful will destroy all 
 the varieties of scale, as the one under treat- 
 
ment is the most difficult of all to overcome. 
 A portion of these experiments are numbered, 
 and the results obtained, stated as observed, at 
 different dates up to this time, October, 1882, 
 
 No. 1. Concentrated lye of the American Lye 
 Co., one pound; water, two gallons. Feb- 
 ruary 22, 1881 Applied by spray upon 
 two peach trees infected by scale; washed in 
 the afternoon when the trees were dry; effect, 
 scale killed ; the tenderest wood was killed also. 
 July 5, 1881 New wood grown over the trees 
 four and five feet long. 
 
 No. 2. Concentrated lye, one pound; water, 
 two gallons. March 10, 1881 Applied by spray 
 upon two peach trees infested by scale, washed 
 in the morning when the trees were damp with 
 dew. July 5, 1881 Scale killed; buds and 
 twigs not injured; fruit abundant and trees 
 most healthy. 
 
 No. 3. Concentrated lye, one and one-half 
 pounds; water, one gallon. June 23, 1881 Ap- 
 plied by pouring from a dipper upon two pear 
 trees infested with scale and with numerous 
 limbs dead. Lye so strong as to burn bark and 
 foliage. August 2, 1881 Scale entirely des- 
 stroyed; bark being restored and new foliage 
 appearing. 
 
 No. 4. Concentrated lye, one pound; water, 
 one gallon. July 5, 1881 Applied by spray 
 upon a large apple tree badly infested by scale; 
 bark and leaves burned. August 2, 1881 Scale 
 killed; green layer of bark being rapidly re- 
 stored and new leaves and blossoms appearing 
 all over the tree. The foregoing trees have 
 since been mostly killed by the application of a 
 low grade of coal oil. 
 
 No. 5. Concentrated lye, one pound; water, 
 one gallon. February, 1881 One almond tree, 
 one Easter Beurre pear tree and two apple trees, 
 grafted, were washed by brush with this 
 strength of lye in order to destroy the red 
 spider and its eggs, which could not be de- 
 stroyed by previous applications of lye, one 
 pound to five gallons, and also one pound to 
 three gallons; another and the main reason 
 being to ascertain the effects of very strong lye 
 upon the trees. No scale upon these trees. 
 This application destroyed the red spider and 
 its eggs on these trees so that it did not appear 
 for months; but, however, later on the trees be- 
 came again infested. While the strong lye will 
 destroy a large number of the eggs of the red 
 spider it is found that all cannot be reached. 
 The effect upon the bark and health of these 
 trees was wonderfully good, the bark being very 
 smooth and having a bright green, velvety ap- 
 pearance and totally free from all moss or other 
 parasites. 
 
 No. 6. Concentrated lye, one pound; water, 
 one gallon. The experiments in this number 
 were made upon a section of orchard in a square 
 block comprising 357 Ickworth plum trees, cut 
 down and grafted into Petite prune; some year- 
 ling prune trees having been put in in places 
 and washed as were the plums, of these 126 
 trees were washed in February, 1881, with the 
 above strong lye, applied with a brush. Among 
 the 357 trees were eight trees badly infested 
 with scale. No others had any scales upon 
 them. The infested trees were scattered about 
 as follows, and washed as indicated: 
 
 No. 10 in first row and 4 in llth row were 
 washed with lye, one pound to three gallons of 
 water. The effect was not quite sufficient to 
 completely destroy the scale, though so in- 
 jured that they did not breed. Afterward 
 these two trees were washed with one pound to 
 one gallon, and this effectually ended the scale. 
 No. 7 in Cfch row, 10 in 7th row, 11 in 12fch 
 row, 8 in 14th row, 3 in 17th row and 11 in 
 17ch row were washed with lye, one pound to 
 one gallon of water, with the effect of com- 
 pletely destroying every scale upon them, and 
 not one has appeared upon any of these trees* 
 since that time. These trees have been in the 
 finest possible condition from, the time of this 
 application. 
 
 Among the trees not washed with the strong 
 lye, two were found, in June, 1882, to have 
 scale upon them; one of these, the top having 
 become badly broken by wind, was dug out and 
 burned, the other was washed soon as discov- 
 ered with the whale-oil soap and sulphur mixt- 
 ure; owing to the foliage upon the tree not 
 every part of it could be touched. Yet, how- 
 ever, the scale was destroyed, so far as could be 
 found. 
 
 No. 7. Concentrated lye, 1 pound to one and 
 one-half gallons water. Five Bartlett pear trees 
 obtained from the nursery and planted in 1881 
 and scattered among a considerable number, al- 
 though carefully examined at the time for scale,, 
 were found in June, 1881, to have a few scales 
 upon them. These were at once washed with 
 the above strength of lye, which destroyed the 
 scale completely upon three of those o trees,so that 
 none subsequently appeared. On two of them, 
 however, a live scale or two must have remained 
 on the trunk of the tree at the surface of the 
 ground untouched by the lye, as in September 
 following a few young scales were discovered, 
 located close to the ground. These were again 
 washed in the same manner. Since that wash- 
 ing no scale has been found upon either of these 
 trees until this month (Oct. 16, 1882). On one 
 of them has been found a few young scale. The 
 tree was immediately washed with the whale- 
 oil soap and sulphur mixture. On another 
 Bartlett pear tree, not, however, numbered with 
 the above, was found some scales, Nov. 7, 1881. 
 This tree, being entirely dormant, was washed 
 with lye one pound to one gallon water, com- 
 pletely destroying the scale, as none can be 
 found on it this year. Among the Yellow Egg 
 plum trees, one was found January, 1882, with 
 scale upon it, and washed at once with lye one 
 pound to one gallon water, and repeated in Feb- 
 ruary. No scale were left, as none can ba found 
 at this date. Another Egg plum tree was found 
 infested in June of this year. To this was ap- 
 plied, by a brush, the whale-oil soap and 
 sulphur mixture with some lye added. 
 No scale can now be found upon it. 
 
 The trees in experiments five, six and seven are 
 in an orchard of 50 acres. I have constantly 
 and carefully watched all these trees, and at 
 this date no scale can be discovered in the en- 
 tire orchard. Should any hereafter appear, the 
 treatment will be by lye one Ib. to one gallon 
 water. With this success in my two years' in- 
 dividual practice, I feel justified in repeating 
 the statement I made at the first State 
 Fruit Growers' Convention, that young orchards 
 
can be kept free from the Aspidiotus perniciosus 
 by the right use of concentrated lye as a winter 
 wash, and the whale oil soap and sulphur mix- 
 ture for summer. 
 
 In the following experiments the trees were 
 all badly infested with scale: 
 
 8. Concentrated lye, one and one-half IBs; wa- 
 ter one gallon. June 24, 1881 Applied to two 
 Clairgeau pear trees; brush used in order to 
 save foliage; many limbs dead from effects of 
 scale. Jane 27 Trees burned considerably; 
 scale killed where reached. July 2d Much of 
 the bark showing a healthier appearance. July 
 23d Trees still better. August 2d No sign of 
 scale; green layer of bark being restored very 
 rapidly; the fruit quite clean, because no scales 
 of second brood were upon it. April 25, 1882 
 Examined the trees, and found a very healthy 
 top. and with new bark where burned with the 
 lye when washed in the summer. All the sur- 
 face was not touched by the lye, and where not 
 washed the scales still existed. Wherever the 
 bark was washed, owing to the time that it was 
 done, it was cracked across. Yet underneath 
 this cracked surface was found new and healthy 
 bark. October 14, 1882 There has been a 
 good growth of new wood this season, and the 
 under bark has maintained its fresh and healthy 
 appearance over entire tree. 
 
 9. Concentrated lye, one and a half K3. ; wa- 
 ter, one gallon. June 24, 1881 Applied on a 
 portion of tree to ascertain the effect upon the 
 stain of bark. July 23i The bark where 
 washed shows much less stain; lighter in color, 
 and the green layer being restored. August 
 2d Stain rapidly disappearing. 
 
 10. Concentrated lye, one fib. ; water, one gal- 
 lon. July 5, 1881 Mixed accurately, and ap- 
 plied same day upon pear tree. July 23d 
 Scale where reached entirely destroyed; bark 
 burned by the lye, but otherwise healthy and 
 good where it was previously sound. April 25, 
 1882, and October 14, 1882 Observations 
 nearly the same as in the preceding number, 
 the bark under the cracked outer layer being 
 all renewed, and with a bright, healthy, green 
 layer free from stain; free growth of new wood 
 during the season. 
 
 11. Concentrated lye, one pound; water, one 
 and one-half gallons. Tree washed same time 
 as above and with about the same results, al- 
 though an unthrifty tree. October 14, 1882 
 The tree had been pretty well destroyed by the 
 scale last year, and shows but a little growth 
 of new wood. 
 
 12. Concentrated lye, one lb.; water, two 
 gallons. Same as above, except that the tree 
 was still more thoroughly ruined by scale, and 
 at this date has not recovered ^but little new 
 wood; what there is, however, being healthy. 
 
 13. Concentrated lye, one lt>:; water, three 
 gallons. This tree had been washed by spray- 
 ing April 1, 1881, with this strength of lye, 
 which proved too weak to destroy the scale. 
 July 23, 1881 Young scale insects covered the 
 tree; the tree was left to itself with that wash- 
 ing. April 25, 1882 Observed that the scale 
 was abundant and fast accomplishing the de- 
 struction of the tree. October, 14, 1882 The 
 tree is dead to within one foot of the ground, 
 but from the collar many new sprouts have 
 grown. 
 
 No. 14. Concentrated lye, 1 lb; water, 5 gals. 
 
 June 23, 1881 Applied to two trees, one 
 slightly and the other badly infested with scale. 
 This wash was used by pouring it upon the 
 trunk of the trees and allowing it to run down 
 and soak into the ground; the tops of the trees 
 were not touched. This experiment was made, 
 as it had been publicly stated that this weak 
 lye used in this manner was an effectual rem- 
 edy. July 2, 1881 No effect produced upon 
 the scale where not reached by the lye. 
 August 2, 1881 No effect other than no- 
 ticed above; scale only injured where touched 
 by the lye, and second brood of young scale in- 
 sects crawling all over the top of the trees. 
 April 25, 1882 Trunk quite clean and 
 healthy, but the top full of scale insects of the 
 last season alive and approaching maturity. 
 October 14, 1882 Tree covered with scale, 
 old and young; the trunk, however, where 
 washed, appearing far more free than the up- 
 per portion; the bark where washed is healthy. 
 
 Use of Kerosene. 
 
 In the following experiments with kerosene, 
 the action of that agent was reported as it then 
 appeared at the date of report, but the subse- 
 quent effects which will now be stated, show 
 how important it is to allow ample time to 
 elapse before coming to a conclusion upon the 
 merits or demerits of a particular proposed 
 remedy. The use of coal oil when the tree is 
 full of sap is plainly shown to be unallowable. 
 These will be detailed as they appeared at the 
 time, and also as seen this season. 
 
 No. 15. Kerosene, low grade and heavy, 110 
 test. June 1, 1881 Applied to two pear trees, 
 spraying, with coarse spray used and oil thrown 
 over the entire trees. June 27, 1881 Observed 
 that the foliage had been killed and the trees 
 considerably affected; scale killed. July 2, 
 1881 New leaf buds coming out. July 23, 
 1881 New foliage all over the trees, and seem- 
 ingly new vigor throughout; new shoots six 
 inches long; no scale to be found, and the green 
 layer of the birk healthy to all appearance. 
 August 2d Foliage increasing rapidly all over 
 the trees, and, apparently, the trees were gain- 
 ing in health. Thus they appeared up to Au- 
 gust, 1881. The observation of these trees on 
 April 25, 1882, showed a very different state; 
 the trees were dead. 
 
 No. 16. Kerosene, high grade, 150 test. June 
 
 1, 1881 Applied by spray upon two pear trees. 
 June 27, 1881 Observed that the foliage had 
 not been killed, but that the scale had all been 
 destroyed; the trees apparently uninjured. 
 July 2d New leaf buds coming forth. August 
 
 2, 1881 Trees appear healthy; foliage unin- 
 jured; scale showing no signs of its presence, 
 and the fruit showing less effects from scale on 
 account of the wash it bad received. April 25, 
 1882 Trees were dead. 
 
 No. 17. Kerosene, high grade Diamond brand, 
 150 test. July 27, 1881 Applied upon two 
 pear trees with a coarse heavy spray over entire 
 trees; trees very badly infested. August 2 
 Effectually destroyed the scale; the trees and 
 foliage apparently entirely healthy. No per- 
 ceptible effect upon the trees, but completely 
 dryiug up the scales, so that they are blown 
 away by the wind. The fruit is not affected by 
 the kerosene, but the scale upon it is killed, 
 and the fruit is very clean. It is observed that 
 
kerosene of 150 test evaporates rapidly, and 
 leaves but little signs of having been applied. 
 April 25, 1882 One tree dead; the other not 
 dead but nearly so. October 14, 1882 Ex- 
 animation showed trees to be dead. 
 
 No. 18. Kerosene, same brand. July 27, 1881 
 Applied upon a pear tree by spray atomizer, 
 which produced a very fine mist only. Aug- 
 ust 2, 1881 The same effects produced as in 
 No. 17; scale appeared to be entirely destroyed; 
 no apparent effect upon tree or foliage. April 
 25, 1S82 Tree not dead, but with many scales 
 upon it. October 14, 1882 Old wood 
 dead, but new wood from near the ground. 
 
 No. 19. Gasoline. July 27, 1881 Applied 
 upon pear tree by heavy syringe spray thor- 
 oughly over the tree and foliage. August 2, 
 1881 Not effectual in destroying the scale; too 
 volatile; many of the insects killed, but a large 
 portion unaffected; no apparent effect upon the 
 tree or foliage at that time; on this tree the 
 young male scales just hatched out were found 
 crawling about. April 25, 1882 The tree has 
 been almost killed by the scale infesting it. 
 October 14, 1882 Tree still alive, with some 
 si<l6 upon it. 
 
 No. 20. Gasoline. July 27, 1881 Applied 
 upon pear tree by the spray atomizer. August 
 2d Result same as the preceding. October 14, 
 1882 This tree did not suffer from the effects 
 of the < ^plication, but this season has made a 
 vigorous growth of new wood quite clean from 
 scale. The foregoing applications of kerosene 
 and gasoline were made in full strength. 
 
 Whale Oil Soap and Sulphur. 
 
 No. 21. Whale oil soap and sulphur mixt- 
 ure 1 lb., water 1 gal. June 23, 1881 Ap- 
 plied by spray over pear tree, covering foliage 
 and fruit thoroughly. July 23d Scale killed; 
 tree gaining in health; green layer of bark be- 
 ing restored; fruit greatly improved in appear- 
 ance. August 2, 1881 Tree still improving, 
 also fruit. April 28, 1882 Tree very healthy 
 and appears clean from scale; green layer of 
 bark being fully restored, and parts of the tree 
 that were nearly killed by the scale are form- 
 ing new bark rapidly; the tree has a very fine 
 top of new growth. October 14, 1882 The 
 tree has grown very thriftily through the sea- 
 son and the wood is all very healthy; some 
 scale are found upon the tree, however. These 
 trees are in an orchard badly infested, and it is 
 to be expected that the insects will return. 
 This wash is an effectual summer wash, and 
 where there is any scale present should be used 
 in the strength here given, as a wash of one- 
 half the strength has proven ineffectual. 
 
 Soft Soap and Sulphur. 
 
 No. 22. Soft soap, one pound; sulphur, one 
 pound; tobacco, one pound; water, three gal- 
 lons. July 5, 1881 Applied upon two trees by 
 spray, covering trees, foliage and fruit thor- 
 oughly. July 23, 1881 Seemed quite effectual 
 at the time; many scale destroyed, but not all; 
 trees, not affected by the wash; fruit improved in 
 appearance. Subsequent observations, however, 
 showed that but little was accomplished in 
 destroying the scale. October 14, 1882 This 
 tree shows an abundance of live scale in all 
 stages of growth. This wash was used with good 
 effect in another orchard, June 1, 1881, on a 
 
 Fellenberg prune tree, clearing it from scale, 
 which, up to this time, have not returned. 
 
 No. 23. Soft soap, one pound; sulphur, 1 
 pound; water, three gallons. 
 
 No. 24. Soft soap, 1 pound; water, 3 gallons; 
 The two washes named above were applied 
 June 23, 1881, and with no effect, neither 
 has it shown any result this season. 
 
 Whale Oil Mixture. 
 
 No. 25. Whale oil, one pint; kerosene, one 
 pint; borax, one ounce; water, one gallon. June 
 23, 1881 Applied by spray to a pear tree at 
 the different dates in 1881; the effect has been 
 observed ; it has been apparent that the oil is 
 decidedly injurious to the tree, applied in this 
 manner or at this time; it is therefore not 
 recommended. Applied to another tree in one- 
 fifth the strength above given; it has no effect 
 upon either scale or tree. April 25, 1882 The 
 tree first treated is nearly dead; but, however, 
 having the top cut off, new wood is coming 
 along; scale appears to be destroyed. October 
 14, 1882 The old wood is dead; the sickly 
 growth of new wood springing out from the 
 lower portion of the tree shows some scale. 
 
 Carbolic Acid. 
 
 No. 26. Carbolic acid, three ozs.j water, two gal- 
 lons. June 23, 1881 Applied by spray upon a 
 pear tree badly infested with scale. June 27, 
 1881 Failed entirely. This tree afforded a con- 
 stant succession of insects in all stages of devel- 
 opment, both male and female. From it some 
 of our most interesting studies were made; we 
 repeat it as it appeared at each visit on that 
 date (June 27, 1881); we found the male insect 
 under its scale partially developed, with wing 
 pads, but wings not yet out. July 2d Found 
 plenty of winged males of the second brood fly- 
 ing and crawling about. July 23d Tree was 
 covered with young female scale insects of the 
 second brood crawling, and with a few of them 
 just located and commencing to be 
 covered with their scale. July 25th A 
 few of the winged male still found; 
 bark scraped clean on this date was in two 
 days covered with young scale and with a slight 
 formation of scale over them. Aug. 2d Tree 
 entirely covered with young scale on this date; 
 two or three winged males were found. April 
 25, 1882 Tree almost dead from effects of 
 scale; top dead and removed and a few feeble 
 shoots coming forth. October 14, 1882 Shoots 
 have grown from the trnnk of the tree to some 
 extent, but the whole having been so seriously 
 infested the tree is considered worthless. 
 
 The entire orchard in which these trees are 
 situated, other than the ones experimented on, 
 from 8 to 26 were washed this past winter with 
 a very low grade of coal oil called "tree wash;" 
 the result is not satisfactory; the owner 
 tells mej(0ctober 14, 1882) that he is satisfied 
 that the oil has seriously injured his trees. 
 
 San Jose. October 25. 1882. 
 
 Experiments with Steam. 
 
 It was at one time thought that steam might 
 be effectually applied for the extermination of 
 insect pests upon trees. In the summer of 1881 
 a test of this agent was made in an orchard near 
 San Jose. A large tent was made to hang upon 
 a frame, which could be run on either side of. 
 
and overhanging the tree; the tent then being 
 dropped, the tree was entirely enclosed in an 
 air-tight bag, into which the steam and other 
 ingredients were forced, and left to act upon 
 the tree and insects as long as was thought nec- 
 essary. 
 
 Horticultural Commissioner D. C. Vestal and 
 myself carefully noted the experiments made 
 and placed the results upon record. These ex 
 periments are also numbered for convenience in 
 describing. 
 
 No. 1. Sept. 8, 1881. An apple tree infested 
 with scale insect, wooiy aphis and other pests, 
 was covered by the tent, under which was hung 
 upon the tree cloths saturated with bi-sulphide 
 carbon, one-half pound. It was thus left for 
 three- fourths of an hour, and then the tent was 
 removed. Result, apparently of no effect. The 
 woolly aphis was not injured, but found crawl- 
 ing about. The red spider was found crawling 
 about; also a small caterpillar was observed 
 unharmed. The scale insects were not affected 
 in any ^ay, so far as could be observed. Sept. 
 12, 1881 Examination made on this date 
 showed that no effect had been made by the ap- 
 plication upon any of the insects mentioned as 
 infesting this tree. Mr. J. H. Wheeler, the 
 maker or the bi sulphide carbon, thought that 
 the agent had not been properly brought into 
 contact with the insects, and for that reason 
 failed to destroy them. 
 
 No. 2. A pear tree was treated with steam 
 forced under the tent covering the tree. The 
 temperature was raised to 165, and maintained 
 for 10 minutes. Observations immediately af- 
 terwards showed that the foliage of the tree 
 and the young wood of the tree waa destroyed. 
 Everything was cooked thoroughly. Septem- 
 ber l2th The tree and the scale were both 
 killed. 
 
 No. 3. An apple tree was treated in the 
 same manner, with steam at 140, 
 for three minutes, and afterwards with 
 sulphur fumes (caused by putting two 
 handsful of sulphur upon live coals) for five 
 minutes. The result showed that the tree 
 did not appear quite so much injured at this 
 time as the preceding tree at first showed, 
 but as seen on September 12 bh the effect was 
 the same. The scale was killed, and also the 
 entire tree, except the oldest part of the trunk. 
 
 No, 4. Apple tree steamed for five minutes 
 at 140; dri^d for five minutes, and then fumed 
 with sulphur for five minutes, llssult the same 
 as the preceding. 
 
 No. 5. Apple tree moderately covered with 
 scale and woolly aphis. Steam applied with 
 which had previously been mixed three gallons 
 of kerosene, pumped into the boiler of a thresh- 
 ing engine. This application was made at 110 
 and maintained for four minutes. September 
 12th No effect was perceptible upon the tree, 
 except that the foliage was somewhat injured. 
 The scale insect was not killed or even injured. 
 The woolly aphis was found alive and uninjured. 
 
 No. 6. Steam and coal oil applied tour min- 
 utes at 140. September 12 Tree pretty nearly 
 killed. Only the oldest wood alive all new 
 wood and buds killed. 
 
 No. 7. Steam and coal oil for six minutes at 
 130; No. 8, same for six minutes at 150; No. 
 9, same for 12 minutes at 120 to 130. This 
 tree was steamed four minutes, and then, after 
 
 an interval of six minutes, was steamed two 
 minutes more. September 12th The result 
 upon these trees was the same. The trees were 
 all destroyed excepting the trunk and oldest 
 wood. 
 
 From these experiments it will be seen that 
 steam cannot be applied in such manner and at 
 a temperature sufficiently high to destroy the 
 insects without, at the same time, destroying 
 the tree. 
 
 During the season of 1881 strong efforts were 
 made to introduce the use of 
 
 Various Patented Mixtures, 
 
 Which were claimed to have great merit in 
 destroying the scale insect. One of these was 
 to be used by simply spreading it on the trunk 
 of the tree, which application it was stated 
 would, through the poisoning of the sap, kill 
 the insects. This, as well as others of a like 
 nature, were given careful consideration and 
 tested, and resulted in entire failure. 
 
 Another method, which was persistently 
 forced upon the public, was that of boring into 
 the trunk of the tree to the centre, and filling 
 the auger hole with the so-called care. A care- 
 ful investigation of many trees so treated was 
 made by Mr. Mathew Cooke, Mr. D. C. Vestal 
 and myself, for the purpose of determining the 
 actual effects, if any, of this treatment. Oct. 
 17, '81, we visited the orchard of one person, 
 who had allowed his name to be used in recom- 
 mending this exterminator, and first Cammed 
 two pear trees bored and the holes filled with 
 the preparation. These trees were found to be 
 covered with live scale insects in all stages of 
 development, and showing no signs of injury. 
 The young female insects were found crawling 
 about the trees in great numbers. The wood, 
 the seasons growth, was covered with scale. 
 An apple tree, the trunk and large limbs of 
 which had been washed the previous winter 
 with strong lye, showed that the scale which 
 completely covered it when the lye was ap- 
 plied were entirely destroyed where the wash 
 had reached, but on the smaller wood which 
 had not been washed with the lye the scale was 
 found alive. This tree had also been bored and 
 treated with the application referred to, and 
 which had no effect whatever. On the trunk 
 of this tree, where the lye had been applied, 
 the green layer of bark was found replacing the 
 old, which had nearly been destroyed by the 
 scale. At another place we examined a pear 
 tree which had been bored and treated with 
 this preparation. This tree was in no manner 
 whatever affected by this so-called remedy, but 
 was completely covered with scale insects in 
 every stage. We found the young females 
 crawling about, and on this tree was found the 
 male scale in the first pupa stage of develop- 
 ment for the third winged brood, and also on 
 this tree was discovered the perfect winged 
 male of the third brood. In no case has the 
 slightest good resulted from these secret and 
 patented preparations. We have treated this 
 subject thus fully because, to our knowledge, 
 prominent and careful horticulturists have been 
 induced to purchase these things at an exhor- 
 bitant charge. 
 
 The treatment of trees by 
 
 Crude Petroleum 
 And its different products has been thoroughly 
 
cited to show the. effrc^e/" of lye as an in- 
 secticide, &?t vsufri.)iefc.'t fact's 'ate staled. 
 
 How the Insects are Spread. 
 
 Attention must be called to the means of 
 spreading this serious pest, the aspidiotus per- 
 niciosus. The system of "return boxes," and 
 packages of any character, is known to be per- 
 nicious and a fruitful source of the spread of 
 all kinds of noxious insects, which, either as 
 insects, eggs or larvre, are fastened to them and 
 taken into the orchard, to be developed in due 
 time, and then to spread devastation to every- 
 thing attacked. Indeed, to me, so obnoxious is 
 the return box that I will not permit one to be 
 brought into the orchard or on the premises. I 
 prefer to pay the cost of new boxes, and give 
 them with the fruit sold. As the female insect 
 has no wings, she can, of course, only be spread 
 about by becoming attached to something by 
 which she is carried to different localities, and 
 by crawling about during the short period after 
 hatching before becoming fixed for life. 
 
 Birds will carry them most frequently about 
 an orchard, and it is thought that one source of 
 danger is little regarded, viz : carrying them 
 about on one's clothing by brushing against in- 
 fested trees. 
 
 If boxes or packages are returned, they should 
 be disinfected as soon as received by dipping in 
 boiling water, to which is added not less than 
 one pound of potash to 25 gallons of the water 
 used. 
 
 The nursery trees sent over the State have 
 been the means of spreading the scale exten- 
 sively, and while nurserymen are anxious to 
 make sale of their trees they must take every 
 precaution to see that their patrons do not suf- 
 fer by neglect to first destroy the scale, which 
 may be done by dipping the trees in a solution 
 of concentrated lye of 1 K>, to 2 gallons of 
 water. I am glad to say that most nurserymen 
 are desirous to do all in their power to destroy 
 the scale. 
 
 Among other means of preventing the spread 
 of scale, thorough and constant cultivation of 
 an orchard should be kept up, and one promi- 
 nent difficulty in the way of eradicating the 
 scale I believe to be the practice so prevalent 
 of growing other small crops in the orchard be- 
 tween the trees. 
 
 It cannot be too strongly impressed upon the 
 mind of every owner of an orchard that he must 
 personally watch his orchard and exercise such 
 constant supervision that no infested tree shall 
 escape observation, and, when found, the proper 
 remedy at once be applied. In the orchard re- 
 ferred to where chance trees have been found 
 infested, no other course would have saved me 
 from the overwhelming spread of the scale. 
 
 The experiments of 1881 and the subsequent 
 use of lye in instances mentioned, indicate the 
 remedy. This should always be used when the 
 tree is dormant, and when the foliage has dis- 
 appeared from the trees. In our climate that 
 time is the winter, and at any time before the 
 trees put forth their buds. 
 
 Applying the Lye. 
 
 The strength of lye should be one It), to one 
 gallon water where trees are infested with 
 scale. Where it is only desired to cleanse the 
 tree from moss one K>. to three or four gallons 
 of water is sufficient. The best method of ap- 
 plying the concentrated lye is by dissolving in 
 boiling water, and throwing it upon the trees 
 with a force pump through 40 or 50 ft. of - 
 jHjl one-half inch rubber hose, to which is at- 
 tached a nozzle, having for its opening a simple 
 straight slit, very narrow in width, and 
 one-sixteenth to one- eighth of an inch long. 
 The best spray tip yet devised is that made at 
 San Jose, called the Merigot Spray Nozzle. 
 The pumps most used for this purpose are the 
 Gould pump and the Merigot pump. The latter 
 is made at San Jose, and is cheaper than the 
 Gould pump. Great care should be taken to 
 cover the tree entirely with the solution of lye, 
 as upon its thorough application depends its 
 success. 
 
 One of the greatest difficulties in the use of 
 strong materials is from the spray falling upon 
 the person of the operator and burning and 
 injuring the skin. la order to overcome 
 this obstacle, I have devised a simple "exten- 
 sion nozzle" of slight cost which is very light 
 and which may be made of any length desired, 
 say from four to 15 ft., or even longer. By the 
 use of this extension it is" perfectly easy to reach 
 and spray any orchard tree without danger and 
 discomfort. The cost of materials and appa- 
 ratus may be given as follows: 
 
 The Gould pump costsabout $10 without acces- 
 saries. The Merigot pump $12. The suction hose 
 and the long hose will cost according to quality 
 used, from 15 cents to 25 cents per foot. 
 
 The Merigot spray tip, if purchased alone, 
 $1.50. If bought with pump, the pump and 
 spray $13. The bamboo extension with globe 
 valve seven ft. long $2.75. All excess in length 
 over seven ft. 25 cents per foot. The concen- 
 trated lye, of the American Lye Co. in one-It) 
 cans by the case of 48 R>3., $3 50 per case. 
 English caustic soda in GOO pouod drums, $33 to 
 $35 per drum. The whale oil soap and sulphur 
 mixture called the "Codlin Moth Wash" is 
 manufactured in San Francisco and the price 
 can be obtained by inquiring of Messrs Allyne 
 & White. 
 
 In conclusion I will give the analysis made 
 v Prof. Hilgard, of the State University, of a 
 sample can of American Lye Co. concentrated 
 lye. The can sent I took from a lot I had been 
 using, and is supposed to be a fair sample of the 
 manufacture. The analysis is as follows: 
 
 Caustic potash 
 
 Caustic soda and carbonate of soda 
 
 8.3 
 91.7 
 
 100.0 
 
 With this I submit my report, expressing 
 my firm conviction that ere long we shall be 
 freed from the ravages of one of the most 
 dreaded pests known to horticulturists. 
 
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