UC-NRLF 
 
UNITED STATES DEPARTMENT OF AGRICULTURE 
 BULLETIN No. 753 
 
 Contribution from the Forest Service 
 HENRY S. GRAVES, Forester 
 
 Washington, D. C. 
 
 March 10, 1919 
 
 THE USE OF WOOD FOR FUEL 
 
 Compiled by the Office of Forest Investigations 
 
 CONTENTS 
 
 Introduction 1 
 
 Wood Instead of Coal for Fuel .... 2 
 
 What to Use for Wood Fuel 6 
 
 Supply of Fuel Wood 8 
 
 Producing and Marketing Wood Fuel . 9 
 
 How to Use Wood Fuel ....... 24 
 
 Efficiency of Wood Fuel. 27 
 
 Page 
 
 Wood Fuel for the Future 33 
 
 Promoting Use of Wood for Fuel . . 35 
 
 Summary ...... 38 
 
 Appendix 39 
 
 Publications on Wood Fuel .... 39 
 
 Recent Publications on Wood Fuel . 39 
 
 Bibliography 40 
 
 WASHINGTON 
 
 GOVERNMENT PRINTING OFFICE 
 1919 
 
 
\ 
 
 
UNITED STATES DEPARTMENT OF AGRICULTURE 
 
 BULLETIN No. 753 
 
 Contribution from the Forest Service. 
 HENRY S. GRAVES, Forester. 
 
 Washington, D. C. 
 
 March 10, 1919 
 
 THE USE OF WOOD FOR FUEL. 
 
 Compiled by the Office of Forest Investigations. 
 
 CONTENTS. 
 
 Page. 
 1 
 2 
 6 
 8 
 9 
 24 
 Efficiency of wood fuel ...................... 27 
 
 Introduction 
 
 Wood instead of coal for fuel 
 
 What to use for wood fuel 
 
 Supply offuelwood 
 
 Producing and marketing wood fuel 
 
 How to use wood fuel 
 
 Page. 
 
 Wood fuel for the future 33 
 
 Promoting use of wood for fuel 35 
 
 Summary 33 
 
 Appendix ' 39 
 
 Publications on wood fuel 39 
 
 Recent publications on wood fuel 39 
 
 Bibliography. 
 
 40 
 
 INTRODUCTION. 
 
 Wood has always been of considerable importance as fuel in this 
 country, and the present emergency has greatly increased its com- 
 parative value for this purpose. Wood is now being cut for fuel in 
 places where for many years it had practically gone out of use. On 
 farms where coal had become the ordinary fuel and was brought in 
 from great distances while wood suitable for fuel went to waste in 
 the neighborhood, wood is now coming into its own again. It is 
 being more used in churches, schools, and homes, and even in fac- 
 tories. The use of wood for fuel saves transportation, it utilizes 
 wood that would otherwise go to waste, and it releases coal for ships 
 and railroads and munitions plants. Heretofore wood has supplied 
 between 10 and 15 per cent of the total amount of fuel used in the 
 United States. The wide distribution of wood fuel supplies, and the 
 fact that they are so located as to save transportation should, under 
 present conditions, lead to a considerable increase in the proportion 
 of wood in our fuel consumption. 
 
 The purpose of this bulletin i is to aid in the conservation of the 
 Nation's coal supply and in the full and proper use of our wood 
 
 1 As is readily apparent, the material used in this bulletin is largely compiled from 
 many sources. Credit has been given as far as it has seemed practical, but in many 
 instances the data are so adapted and changed that a specific reference would be mis- 
 leading. Information has been obtained from State wood-fuel and Forest Service publi- 
 cations mainly, but miscellaneous data and tables have been drawn from everywhere. 
 This general statement is made in order to acknowledge help from sources not specifically 
 mentioned. 
 
 477600 
 
2 ,\*. J : B'PL&ETllSr 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 resources to prevent the recurrence of such a fuel shortage as occurred 
 during the winter of 1917-18, by indicating the best and most eco- 
 nomical methods of cutting, distributing, and using wood for fuel. 
 Uneconomical methods of handling the wood increase the cost and 
 waste the product, careless methods of cutting the trees may endanger 
 the future supply, and the reckless use of shade or ornamental trees 
 for fuel is an unjustifiable extravagance. 
 
 In the utilization of the forests of the country, including farm 
 woodlands, a great deal of wood material is produced which can not 
 find a use other than as fuel wood. While some of it is used for 
 acid wood, charcoal, etc., most of it is left for fuel or wasted. 
 
 Since many of the trees in our forests are fit only for fuel, they will 
 not be cut unless there is a demand for fuel wood. Improvement 
 cuttings, which take the small, diseased, or defective trees, can not be 
 profitably made in many cases unless there is such a demand. Thin- 
 nings can frequently be made to pay for themselves if the material 
 is used for fuel. Sometimes products of thinnings can be used for 
 other purposes than fuel, but more often they can not. As proper 
 thinnings and improvement cuttings are a great stimulus to increased 
 production and at the same time improve the quality of the timber, 
 a fuel wood demand opens up a great opportunity for forest im- 
 provement and, if widespread and continued, will produce a vast total 
 effect for the better in the character and quality of our forest re- 
 sources. 
 
 Wood waste occurs at every stage of the manufacture of wood 
 products, from the lumber operations through the milling process 
 and in the special processes necessary to shape the article into its 
 final form. A wide use of wood fuel affords a market for this waste, 
 which would otherwise be lost. 
 
 Preparing wood for fuel involves slightly more labor than is 
 required to produce coal. It is, however, usually widely scattered 
 labor which is used in wood cutting and hauling, and no increased 
 demand on labor is really made. On most farms there is plenty of 
 time during the winter for both men and teams to work at getting 
 out wood. 
 
 WOOD INSTEAD OF COAL FOR FUEL. 
 
 USE OF WOOD SHOULD BE LARGELY INCREASED IN RURAL DISTRICTS. 
 
 Who can with the least hardship restrict his consumption of coal ? 
 Certain classes of consumers require concentrated fuel, such as coal 
 or crude oil ; others can use other fuels, but at a considerable disad- 
 vantage. Most manufacturers are unable to substitute wood for coal 
 to any great extent because of the character of their heating and 
 power plants and because of their location, which involves railroad 
 
THE USE OF WOOD FOR FUEL. 3 
 
 haul for wood. For similar reasons domestic consumers in the cities 
 can not well use wood to any great extent. Wholesale rail trans- 
 portation of fuel wood is not desirable because of its bulk as com- 
 pared with coal of the same heating value. The substitution can best 
 be made in places where team-hauled wood will take the place of 
 rail-hauled coal. Farmers who own woodlands and villagers who 
 can buy wood from near-by farms can reduce their consumption of 
 coal with least inconvenience to themselves and with the greatest 
 benefit to the public interest. 
 
 Because of the large proportion of wood normally used in the 
 South and the long hauls involved in the West it is not likely that 
 the use of wood for fuel can be greatly increased in those regions. 
 In New England, New York, New Jersey, Pennsylvania, Ohio, In- 
 diana, Illinois, Iowa, Missouri, and the Lake States it ought to be 
 entirely practicable in many cases to replace coal with wood. In 
 these 17 States is a rural population of about 20,000,000, which is 
 estimated to use annually 18,000,000 tons of coal. If by substituting 
 wood one-quarter less coal could be burned on farms and one-tenth 
 less in villages, the total saving would amount to nearly 3,000,000 
 tons, or between 65,000 and 70,000 carloads. 
 
 For many uses, and particularly for summer-time use, wood is a 
 more convenient and cheaper fuel than coal. Churches, halls, summer 
 cottages, and other buildings where heat is wanted only occasionally, 
 and then on short notice, find wood more satisfactory for this 
 purpose. 
 
 PRESENT USE OF WOOD FUEL. 
 
 Up to the present time practically no systematic attempt has 
 been made to take a census of the wood fuel cut or on hand each year. 
 Wood seems to be the only form of fuel on which annual statistics 
 of production are not available. 
 
 In 1916 and 1917 the Bureau of Crop Estimates in the Department 
 of Agriculture secured estimates of the number of cords used on the 
 farms but not the total amount cut. It is understood that in 1918 
 the amount sold from the farm annually will be obtained also, thus 
 showing the total cut. 
 
 According to figures collected by the Bureau of Crop Estimates 
 (see Table 1) about 83,000,000 cords of wood fuel were used in 1917 
 on the farms of the United States. Similar estimates made in 
 December, 1916, indicated that about 82,000,000 cords were used. 
 It is likely that the total amount consumed on farms and in villages 
 and cities is upwards of 100,000,000 cords annually. In these esti- 
 mates, and in all other references to " cord " in this bulletin, unless 
 otherwise stated, a cord is reckoned as 128 stacked cubic feet i. e., a 
 pile 8 by 4 by 4 feet. 
 
BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 The value of wood advanced more than 24 per cent from December, 
 1916, to December, 1917. On the basis of 1917 prices reported, the 
 value of firewood used on farms of the United States is about 
 $283,000,000, or $43.13 per farm. 
 
 TABLE 1. Wood fuel used on farms. 
 
 
 Number 
 of farms 
 1917 
 (esti- 
 mated). 
 
 Cords 
 per 
 farm. 
 
 Number 
 of cords 
 per 
 State. 
 
 Value per cord. 
 
 Value of wood used 
 on basis of Decem- 
 ber, 1917, values. 
 
 Decem- 
 ber, 
 1917. 
 
 Decem- 
 ber, 
 1916. 
 
 Value 
 per farm. 
 
 Total 
 value. 
 
 Maine 
 
 60,000 
 27,000 
 33,000 
 37,000 
 5.000 
 27,000 
 215,000 
 33,000 
 218,000 
 11.000 
 50,000 
 190,000 
 99,000 
 259,000 
 185,000 
 300,000 
 55,000 
 271,000 
 215,000 
 250,000 
 209,000 
 180,000 
 157,000 
 215,000 
 275,000 
 90,000 
 90,000 
 135,000 
 180,000 
 265,000 
 250,000 
 270,000 
 285,000 
 122,000 
 430,000 
 210,000 
 225,000 
 35,000 
 15,000 
 55,000 
 45,000 
 12,000 
 23,000 
 3,000 
 36,000 
 65,000 
 50,000 
 95,000 
 
 13 
 12 
 15 
 10 
 10 
 13 
 14 
 8 
 9 
 13 
 13 
 18 
 16 
 17 
 14 
 16 
 11 
 13 
 12 
 9 
 13 
 13 
 11 
 5 
 13 
 3 
 3 
 3 
 6 
 18 
 19 
 18 
 16 
 15 
 9 
 10 
 19 
 10 
 10 
 6 
 9 
 9 
 8 
 11 
 9 
 11 
 12 
 10 
 
 780,000 
 324,000 
 495,000 
 370, 000 
 50,000 
 351,000 
 3,010,000 
 264,000 
 1,962,000 
 143, 000 
 650,000 
 3,420,000 
 1,584,000 
 4,403,000 
 2, 590, 000 
 4,800,000 
 605,000 
 3,523,000 
 2,580,000 
 2,250,000 
 2,717,000 
 2,340,000 
 1,727,000 
 1,075,000 
 3,575,000 
 270,000 
 270,000 
 405,000 
 1,080,000 
 4,770,000 
 4,750,000 
 4,860,000 
 4,560,000 
 1,830,000 
 3,870,000 
 2,100,000 
 4,275,000 
 350,000 
 150,000 
 330,000 
 405,000 
 108,000 
 184,000 
 33,000 
 324,000 
 715,000 
 600,000 
 950,000 
 
 $6.40 
 6.40 
 6.00 
 6.35 
 5.80 
 6.00 
 4.60 
 5.10 
 3.50 
 4.20 
 4.15 
 3.20 
 2.90 
 2.75 
 3.00 
 2.50 
 3.10 
 3.60 
 3.70 
 4.60 
 5.25 
 5.50 
 5.40 
 4.70 
 3.20 
 7.50 
 6.20 
 4.25 
 4.25 
 2.20 
 2.20 
 2.00 
 2.30 
 2.50 
 3.40 
 3.10 
 2.35 
 4.80 
 4.50 
 4.50 
 4.20 
 5.75 
 5.00 
 7.00 
 5.00 
 5.20 
 4.70 
 7.40 
 
 $4.50 
 4.60 
 4.35 
 4.70 
 4.00 
 4.50 
 4.00 
 4.00 
 2.60 
 3.10 
 3.20 
 2.40 
 2.30 
 2.10 
 2.10 
 2.00 
 2.60 
 3.00 
 3.30 
 3.40 
 4.00 
 4.20 
 4.30 
 4.20 
 2.60 
 6.40 
 6.00 
 3.90 
 3.30 
 1.70 
 1.75 
 1.80 
 1.90 
 2.25 
 2.80 
 2.75 
 2.00 
 4.50 
 3.80 
 3.70 
 4.00 
 5.40 
 4.00 
 6.00 
 4.60 
 4.50 
 3.90 
 5.80 
 
 $83.20 
 76.80 
 90.00 
 63.50 
 58.00 
 78.00 
 64.40 
 40.80 
 31.50 
 54.60 
 53.95 
 57.60 
 46.40 
 46.75 
 42.00 
 40.00 
 34.10 
 46.80 
 44.40 
 41.40 
 68.25 
 71.50 
 59.40 
 23.50 
 41.60 
 22.50 
 18.60 
 12.75 
 25.50 
 39.60 
 41.80 
 36.00 
 36.80 
 37.50 
 30.60 
 31.00 
 44.65 
 48.00 
 45.00 
 27.00 
 37.80 
 51.75 
 40.00 
 77.00 
 45.00 
 57.20 
 56.40 
 74.00 
 
 14,992,000 
 2.074.000 
 2,970,000 
 2,350,000 
 290,000 
 2,106,000 
 13,846,000 
 1,346,000 
 6,867,000 
 601,000 
 2,698,000 
 10,944.000 
 4,594,000 
 12,108,000 
 7,770,000 
 12,000,000 
 1,876,000 
 12,683,000 
 9,546,000 
 10,350,000 
 14,264,000 
 12,870,000 
 9,326,000 
 5,052,000 
 11,440,000 
 2,025,000 
 1,674,000 
 1,721,000 
 4, 590, 000 
 10,494,000 
 10,450,000 
 9,720,000 
 10,488,000 
 4,575,000 
 13, 158, 000 
 6,510,000 
 10,046,000 
 1,680,000 
 675,000 
 1,485,000 
 1,701,000 
 621,000 
 920,000 
 231,000 
 1,620,000 
 3,718,000 
 2,820,000 
 7,030,000 
 
 New Hampshire 
 
 Vermont 
 
 Massachusetts 
 
 Rhode Island 
 
 Connecticut 
 
 New York 
 
 New Jersey 
 
 Pennsylvania 
 
 Delaware 
 
 Maryland 
 
 Virginia 
 
 West Virginia 
 
 North Carolina 
 
 South Carolina 
 
 Georgia 
 
 Florida 
 
 Ohio 
 
 Indiana 
 
 Illinois 
 
 Michigan . 
 
 Wisconsin 
 
 Minnesota 
 
 Iowa 
 
 Missouri 
 
 North Dakota 
 
 South Dakota 
 
 Nebraska 
 
 Kansas . ... 
 
 Kentucky 
 
 Tennessee 
 
 Alabama 
 
 Mississippi 
 
 Louisiana 
 
 Texas 
 
 Oklahoma 
 
 Arkansas 
 
 Montana 
 
 Wyoming 
 
 Colorado 
 
 New Mexico 
 
 Arizona 
 
 Utah 
 
 Nevada 
 
 Idaho 
 
 Washington 
 
 Oregon 
 
 California 
 
 United States 
 
 6,562,000 
 
 12.6 
 
 82,777,000 
 
 3.42 
 
 2.75 
 
 43.13 
 
 282,915,000 
 
 
Bui. 753, U. S. Dept. of Agriculture. 
 
 PLATE I. 
 
 
 FIG. I. SAWING EMERGENCY WOOD TO RELIEVE COAL SHORTAGE, GREENVILLE, 
 TENN., JANUARY 18, 1918. 
 
 FIG. 2.-A LOAD OF STOVE WOOD IN NORTHERN MICHIGAN (ONTONAGON 
 
 COUNTY). 
 
THE USE OF WOOD FOR FUEL. 
 
 A detailed survey of the use of wood and coal in selected localities 
 in a number of States gave the following comparative data : 
 
 TABLE 2. Average annual consumption of coal and icood per family on farms in 
 
 eight States. 1 
 
 State and county. 
 
 Coal, per family. 
 
 Wood, per family. 
 
 Tons. 
 
 Value. 
 
 Cords. 
 
 Value. 
 
 Vermont (Lamoille) 
 
 0.1 
 2.5 
 4.9 
 5.7 
 3.0 
 3.9 
 
 $1.01 
 16.00 
 26.90 
 23.70 
 20.70 
 29.57 
 
 14.3 
 12.2 
 6.2 
 12.0 
 7.5 
 4.8 
 14.0 
 17.8 
 
 $65.40 
 54.80 
 19.00 
 32.50 
 38.80 
 22.40 
 43.58 
 51.60 
 
 New York (Otsego) 
 
 Pennsylvania ( Bucks) 
 
 Ohio (Champaign) - ... 
 
 
 Iowa ( Montgomery) 
 
 North Carolina (Gaston) 
 
 Georgia (Troup) 
 
 
 
 
 2.5 
 
 14.74 
 
 11.1 
 
 41.01 
 
 
 i From Farmers' Bulletin 635, " What the Farm Contributes Directly to the Farmer's Living," by W. C. 
 Funk. See also Department of Agriculture Bulletin 410, "Value to Farm Families of Food, Fuel, and Use 
 of House," by W. C. Funk. 
 
 TABLE 3. Average annual consumption of wood per person in eight States, show- 
 ing the per cent of wood bought and the per cent furnished by the farm. 
 
 State and county. 
 
 Per person. 
 
 Per cent. 
 
 Cords. 
 
 Value. 
 
 Bought. 
 
 Furnished 
 by farm. 
 
 Vermont (Lamoille) 
 
 3.0 
 3.1 
 1.2 
 2,9 
 1.1 
 1.7 
 3.1 
 3.3 
 
 $13.62 
 13.70 
 3.65 
 7.93 
 5.34 
 8.82 
 9.68 
 9.56 
 
 3.0 
 1-8 
 5.8 
 6.2 
 7.7 
 
 97.0 
 98.2 
 94.2 
 93.8 
 92.3 
 100.0 
 96.1 
 100.0 
 
 New York (Otsego) 
 
 Pennsylvania ( Bucks) 
 
 Ohio (Champaign) . . . 
 
 Wisconsin (Jefferson) 
 
 Iowa (Montgomery) 
 
 North Carolina (Gaston) 
 
 3.9 
 
 Georgia (Troup) 
 
 Average. . 
 
 
 2.4 
 
 9.04 
 
 3.55 
 
 96.45 
 
 
 INDUSTRIAL USE OF WOOD FUEL. 
 
 The use of wood fuel by factories reached its greatest development 
 in New England during the acute coal shortage of the winter of 
 1917-18, because this section was practically shut off for a time from 
 all supplies of bituminous coal, which is the factory fuel. Com- 
 plete information is not available on the quantity of wood used by 
 the factories or how extensive its use was throughout New England, 
 but it is known that a great many factories were forced to use wood 
 to keep in operation. One dealer reported that he had shipped 5,500 
 cords of wood to the factories in eastern Massachusetts. 
 
 Such use of wood will come about only through necessity, as it 
 costs at least three times as much as soft coal. The only reason for 
 using it, therefore, is to keep the factories running. This points to 
 the fact that in wood fuel the country has a reserve or substitute fuel 
 which can be drawn upon in an emergency, not only to supply domes- 
 
6 BULLETIN 753, TJ.' S. DEPARTMENT OF AGRICULTURE. 
 
 tic consumption but to keep the factories running, although it may 
 not be so efficient in the latter case as coal. Instead of waiting for 
 emergency conditions to arrive, it would be well for both domestic 
 and industrial users of fuel to plan on wood reserves in case the 
 main reliance, coal, is not forthcoming. 
 
 It has been reported that cotton mills in South Carolina and else- 
 where throughout the South are laying in wood to supply the mills 
 in case of shortage, in addition to their usual supplies of wood for 
 the operatives. 
 
 It is, of course, not desirable to use railroad transportation for 
 wood fuel to factories unless there is no coal to haul. Then wood may 
 be moved by rail to avoid shutting down. Many factories are so 
 located at points away from large centers that wood can be used 
 without shipping, and as in the aggregate they consume a large 
 amount of fuel, a change to wood would be an appreciable help. 
 
 WHAT TO USE FOR WOOD FUEL. 
 
 THINNINGS ANI> IMPROVEMENT CUTTINGS. 
 
 The great bulk of the wood-fuel supply in farming regions should 
 come from thinnings and improvement cuttings on farm woodlands. 
 Except under stress of emergency, trees which will produce lumber 
 or other material of higher value than cordwood should not be cut 
 for fuel. 
 
 Trees which are better suited for fuel than for any other purpose, 
 and whose removal will be of benefit to the remaining stand, are : 
 
 1. Sound standing and down dead trees. 
 
 2. Trees diseased or seriously injured by insect attacks, or those 
 extremely liable to such injury, such as chestnut in the region subject 
 to blight, or birch in the gypsy-moth area ; badly fire-scarred trees. 
 
 3. Crooked trees and large-crowned short-boled trees which will 
 not make good lumber and which are crowding or overtopping others. 
 
 4. Trees which have been overtopped by others and their growth 
 stunted. 
 
 5. Trees of the less valuable species where they are crowding more 
 valuable ones, as beech, block oak, birch, hard maple, white oak, or 
 white pine. 
 
 6. Slow-growing trees which are crowding fast-growing species of 
 equal value. 
 
 TREES ON OLD PASTURES. 
 
 On many farms former pastures have become overgrown with 
 red cedar, gray birch, aspen, pine, or other trees. The trees came in 
 slowly and through neglect were allowed to steal much of the pasture. 
 If fuel is to be cut somewhere on the farm, such land as this should 
 be drawn upon first of all and redeemed by removing all the trees and 
 
THE USE OF WOOD FOR FUEL. 7 
 
 restoring the land to grass. Also, uncleared corners of fields or 
 patches of agricultural land within the border of the wood lot may be 
 cut clean, the wood used for fuel, and the land eventually farmed. 
 The expense of clearing is thus largely or entirely met by the value 
 of the. fuel produced. 
 
 TOPS AND LOPS, 
 
 Thousands of cords of wood from the tops and limbs of trees felled 
 in lumbering operations rot annually or furnish fuel for forest fires. 
 Ordinarily this waste can not be avoided, because lumbering is most 
 important in the less thinly populated parts of the country, and long 
 hauls to cordwood markets are too costly. Sometimes, however, 
 farmers overlook near-by woods operations as sources of fuel. The 
 material is already down and can be worked up easily into cordwood. 
 Owners of cut-over land usually are glad to have such material re- 
 moved. 
 
 MILL WASTE. 
 
 Mill waste is very widely used as fuel in the neighborhood of saw- 
 mills and woodworking plants. Much of this refuse is burned to sup- 
 ply power for the mills themselves, but considerable is used as fuel by 
 individuals and in some regions by other manufacturers. In many 
 instances there are still large amounts of this material going to waste 
 which could be made available for fuel. 
 
 SAWDUST BRIQUETS. 
 
 There are now at least three firms on the Pacific coast engaged in 
 the manufacture of sawdust briquetting machinery, and at least three 
 plants for the manufacture of this fuel have been established there. 
 
 The main market for briquets will probably be for domestic use 
 where the cleanliness and easy kindling qualities of the briquet are 
 a fine asset. For this use the briquet might be able to compete with 
 coal at only $8.50 a ton, the housewife being willing to pay a little 
 more for the same heat value on account of these desirable proper- 
 ties. The almost total absence of ash, the absolute absence of clinker, 
 and the lack of smoke are great advantages of briquets over coal. 
 
 In competing with cordwood the briquet has certain advantages, 
 such as requiring less labor in preparing for the fire, containing less 
 moisture and more wood per pound, and obviating the need for 
 kindling wood. 
 
 The best chance for the success of the wood or sawdust briquet 
 is in those regions where sawdust is abundant and coal is expensive. 
 The region best fulfilling these conditions in this country is the 
 Pacific coast, and it is a significant fact that the companies now 
 establishing the industry in America are all, as far as the author 
 knows, on the Pacific coast. 
 
8 
 
 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 CHARCOAL. 
 
 In England it is said that the war has caused a revival of the dying 
 charcoal industry. A great deal has been done with this fuel and 
 there is a possibility of a like interest being aroused in this country 
 as fuel conditions become acute. There are doubtless many places 
 in the wooded districts of the East, especially near large cities, 
 where charoal can be made to advantage in the next few years. 
 Charcoal has a larger heating power per cubic foot than wood, a ton 
 yielding about 2,000 horsepower, and it is cheaper to transport on 
 account of its light weight. 1 
 
 Table 4 gives the production of charcoal in the United States in 
 1909. It is reported that Michigan and Wisconsin now lead in char- 
 coal production. 
 
 TABLE 4. Charcoal production in 1909* 
 
 State. 
 
 Quantity. 
 
 Value. 
 
 Michigan 
 
 Bushels. 
 13,514,106 
 
 $868,003 
 
 New York : 
 
 5, 147, 160 
 
 287, 103 
 
 Pennsylvania . 
 
 16,357,598 
 
 936, 357 
 
 All other States 
 
 3,998,383 
 
 260, 181 
 
 
 
 
 Total ... 
 
 39,017,247 
 
 2,351,644 
 
 
 
 
 i Thirteenth Census, IT. S. 1910, vol. 10, p. 622. 
 SUPPLY OF FUEL WOOD. 
 
 With the increased use of wood fuel which is likely to continue 
 for several years, it is important to know how much fuel wood there 
 is in the country and its local distribution and availability. An 
 estimate of the total amount of firewood has never been made. Ten- 
 tative figures show the following cords per farm in certain selected 
 regions : 
 
 No. of cords 
 Region. per farm. 
 
 Northern Vermont 952 
 
 Southeastern Pennsylvania- 218 
 
 Southern Indiana 474 
 
 Central Indiana 167 
 
 Northern Indiana 344 
 
 Northern Wisconsin - 317 
 
 Southern Minnesota 256 
 
 Eastern Iowa 
 
 Southeastern Nebraska 
 
 Central North Carolina - 1> 231 
 
 Northeastern South Carolina - 1,978 
 
 Central Tennessee 
 
 Northern Alabama ! 660 
 
 Northern Louisiana - 2, 315 
 
 Southern Missouri 
 
 Average 739 
 
 1 " Logging and Lumbering," by C. A. Schenck. 
 
Bui. 753, U. S. Dept. of Agriculture. 
 
 PLATE 1 1 
 
 FIG. I. UNLOADING CORDWOOD FOR FUEL FROM SAILBOATS AT WHARVES, 
 WASHINGTON, D. C. 
 
 FIG. 2. VIEW OF TOP OF STACKS OF CORDWOOD IN ONE YARD AT WASHINGTON, 
 
 D. C. 
 
 Capacity of yard 5,000 cords. 
 
Bui. 753, U. S. Dept. of Agriculture. 
 
 PLATE 1 1 1 
 
 FIG. I. INDUSTRIAL USE OF WOOD FUEL. STORED WOOD FUEL RESERVE OF 
 A NEW ENGLAND FACTORY. 
 
 This supply was obtained in anticipation of a coal shortage. Photo by W. D. Clark, published 
 in American Forestry, June, 1918. 
 
 FIG. 2,-FiRiNG WITH WOOD FUEL; FURNACES IN A NEW ENGLAND FACTORY 
 EQUIPPED WITH AUTOMATIC STOKERS FOR COAL. 
 
 Photo by W. D. Clark, published in American Forestry, June, 1918. 
 
THE USE OF WOOD FOR FUEL. 9 
 
 On the farms alone the total area of woodland in the eastern 
 United States is approximately 143,392,000 acres. The first tier of 
 States just west of the Mississippi has a great deal of timber, espe- 
 cially northern Minnesota, southern Missouri, Arkansas, Louisiana, 
 southeastern Oklahoma, and eastern Texas. In the West the 
 wooded areas are for the most part restricted to the mountains. An 
 average of 10 cords per acre, which seems reasonable, would give 
 one and one-half billions of cords for the region east of the Missis- 
 sippi. 
 
 At the average rate of consumption on the farm itself, 12.6 cords 
 per year, 739 cords will last 58 years. On the average this would 
 be ample time to replace the stands and thus continue the supply 
 indefinitely. As a fact, however, the woodland area is in many re- 
 gions constantly shrinking as a result of land clearing for agricul- 
 tural use and grazing. Thus unless care is taken of that which 
 remains the future supply of fuel wood will be materially reduced. 
 
 The supply of wood fuel in any particular locality depends on 
 more than the total amount of timber. Part of it will be on the 
 land which is suitable for clearing for agriculture, and which will 
 be cleared and improved in the near future. Obviously, the timber 
 on such tracts can all be cut. More will be found on land which 
 should be retained in woodland, and here the question is how much 
 can be cut out safely. As a rule, only a certain percentage can be 
 cut without jeopardizing the forest resources of the future. There 
 is the further question of how much of the wood cut is available 
 for fuel. The trees which are cut may be suitable for lumber, ties, 
 telephone poles, and other higher uses. Therefore, it is essential to 
 know not only the total amount of wood but the amount of fuel 
 wood which can come out without injury to the forest. Only by 
 means of a survey covering these points can a practical and compre- 
 hensive plan be developed to coordinate the supply and use of wood 
 fuel within a given region with other forms of fuel which may be 
 available. 
 
 PRODUCING AND MARKETING WOOD FUEL. 
 
 STUMPAGE. 
 
 The first item of cost in producing wood fuel is the price reckoned 
 or paid for stumpage. Stumpage for this purpose ranges in price 
 from nothing to $5 per cord, depending somewhat upon the region, 
 the kind and quality of timber, and the ideas of the owner. In remote 
 districts where land is being cleared the standing cordwood material 
 is sometimes given away. Slash from lumbering operations is also 
 frequently given away for the cutting or is sold at a nominal price. 
 
 Timber of better quality than cordwood material may naturally be 
 expected to sell for higher prices than seems justified when compared 
 89354 18 2 
 
10 
 
 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 with reasonable cordwood stumpage prices. Such material should, 
 however, not be so used except in cases of emergency, when other 
 stumpage can not be secured. It is reasonable that higher prices 
 should be paid for stumpage when the area is to be cut clear than 
 when only an improvement cutting is to be made, since the latter 
 method increases the cost of cutting somewhat and besides takes 
 material of the least value, the removal of which is a distinct benefit 
 to the forest. In many cases an owner can well afford to give mate- 
 rial from improvement cuttings or thinnings to anyone who will 
 cut it. 
 
 Average stumpage prices ordinarily range from 50 cents to $1.50 
 per cord. 
 
 ESTIMATING STANDING CORDWOOD. 
 
 While cordwood is generally sold on the basis of measurement after 
 it is cut and corded up, it is frequently desirable, especially in case 
 of buying entire tracts, to estimate the amount of wood while still 
 standing. This can be done by methods similar to those used for 
 saw timber. Table 5 1 shows roughly the number of trees of different 
 diameters required to make a cord. 
 
 TABLE 5. Number of trees required to yield 1 cord. 
 
 Diameter of tree (breast high, outside bark). 
 
 Hardwoods. 
 
 Soft- 
 woods. 
 
 Northern 
 (beech 
 birch, 
 maple, 
 etc.). 
 
 Southern 
 (chestnut, 
 oak, hick- 
 ory, etc.). 
 
 Inches. 
 2.. 
 
 
 170 
 90 
 50 
 25 
 17 
 13 
 9 
 7 
 6 
 5 
 4 
 3.4 
 3.0 
 2.5 
 2.2 
 2.0 
 1.8 
 1.5 
 1.3 
 1.2 
 1.1 
 1.0 
 .9 
 
 
 3 . 
 
 
 
 4 
 
 
 
 5.. 
 
 35 
 20 
 15 
 11 
 8 
 6 
 5 
 4 
 3.5 
 3.0 
 2.5 
 2.0 
 1.7 
 1.5 
 1.3 
 1.2 
 1.0 
 .9 
 .8 
 .7 
 
 
 6 
 
 
 7 
 
 20 
 13 
 10 
 8 
 7 
 6 
 4.5 
 3.7 
 3.0 
 2.5 
 2.1 
 1.9 
 1.6 
 1.5 
 1.4 
 1.2 
 1.1 
 1.0 
 
 8 . 
 
 9 
 
 10.. 
 
 11 . 
 
 12 
 
 13. . 
 
 14 
 
 15... 
 
 16.. 
 
 17. . 
 
 18 
 
 19. .. 
 
 20 
 
 21 
 
 22 
 
 23. . 
 
 24 
 
 
 The figures given are for trees of average height; allowances 
 should be made in case of unusually short or tall timber. 
 
 i" Measuring and Marketing Woodlot Products," Farmers' Bulletin 715, by W. B. 
 Mattoon and W. B. Barrows. 
 
THE USE OF WOOD FOR FUEL. 11 
 
 FELLING. 
 
 On the farms a time when labor can not be used at other work is 
 the best time to cut wood; winter, late fall, and early spring are 
 therefore generally the seasons when most wood fuel is cut. In the 
 South, where the slack season comes at a different time, summer 
 may prove the best season. However, there is no good reason why, 
 if labor is available, fuel wood may not be cut at any time. 
 
 In the case of hardwoods which reproduce readily from sprouts 
 the time of cutting is of some importance. The sprouts will start 
 immediately if the timber is cut in the summer or early fall but 
 will not be strong enough to stand the winter, with the result that 
 the reproduction will be winter-killed. On the other hand, if the 
 timber is cut in the winter the sprouts will grow during the spring 
 and summer to such a size and hardihood as to be immune from 
 winter-killing. Winter cutting should therefore be practiced with 
 species which sprout, if reproduction is desired. 
 
 Cordwood is generally felled and cut into 4-foot or sled lengths 
 with axes, or in some cases where larger trees are cut, with crosscut 
 saws. Owing to the small size of the material generally cut this is 
 the most economical method of felling the trees. A number of 
 power-driven tree- felling machines have been devised, but none of 
 them have proved practical, and even if they should become so their 
 value would be in felling trees of large size. 
 
 The cost of cutting cordwood varies with the prevailing wages 
 of the region and with the kind of timber cut. Woodcutters' wages 
 run from less than $2 to more than $4 per day, or where paid by the 
 cord, as is general in some regions, from about $2 to $3.50 per cord. 
 
 The quantity of wood which can be cut per day per man. is, of 
 course, the real basis of the cutting cost and depends most on the 
 skill of the workman and on the kind of wood. Inefficient labor will 
 produce but one-half cord of hardwood or 1 cord of softwood per 
 day, whereas good skilled workmen will cut from 1J to 2 cords of 
 hardwood or from 3 to 4 cords of softwood per day. In one instance 
 men inexperienced in timber work, such as business men from town, 
 cut in hardwoods at the rate of two-thirds of a cord per day for the 
 first day. 
 
 These figures include both felling the trees and cutting them up 
 into 4-foot lengths. If material is cut sled length, as is frequently 
 done, more can be cut in a day. 
 
 SKIDDING AND HAULING. 
 
 In probably the majority of cases the practice is to cut wood into 
 4- foot lengths and pile it close to where the trees are cut, and to haul 
 it direct from these piles to consumers. 
 
12 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 In many cases, however, the trees are merely trimmed or cut into 
 sled lengths and hauled to the consumer to be sawed into stove 
 lengths, or to central points in the woodlot or along a road to be 
 cut up and piled for future hauling. It is possible that extension of 
 this practice may in many instances considerably reduce the cost of 
 producing wood fuel, both by reducing the amount of hand labor 
 required in cutting up the material, in centralizing the work of cut- 
 ting it up, and in increasing the amount which can be hauled by re- 
 ducing its weight through seasoning. 
 
 Skidding or hauling out to a roadway or central point should not 
 cost over $1 per cord. 
 
 SAWING AND SPLITTING. 
 
 Stove wood is no longer " bucked up " by hand with a bucksaw, 
 except in isolated cases. Few men can saw more than from 1^ to 2 
 cords of 4-foot wood into 16-inch lengths in a day, while with power 
 saws of from 6 to 10 horsepower a three-man crew can saw up from 
 10 to 15 cords per day. 
 
 For ordinary use a 24 or 26.-inch circular saw, driven by a 6 to 12 
 horsepower gasoline or kerosene engine, is used. The engine and 
 saw frame are mounted on a truck so as to be readily moved from 
 place to place. Long sticks can be cut up by such a saw as easily 
 as 4- foot pieces, except that in case of larger wood one or more addi- 
 tional men will be required to pass wood to the saw. At the present 
 time complete sawing outfits cost from $200 to $500, depending on 
 the horsepower and the size of the saw. Saw blades cost from $6 to 
 $12, and saw frames from $30 to $40. 
 
 Farmers who do not have this equipment and whose requirements 
 will not warrant such an investment may hire such a saw and engine 
 and exchange the necessary labor in its operation within the com- 
 munity, as is frequently done in grain thrashing. Many have gaso- 
 line or kerosene engines or tractors, and a small portable saw would 
 therefore be a comparatively minor investment and would pay for 
 itself in working up the average wood lot. It could be used every 
 winter in cutting the yearly supply as well as a surplus which might 
 be marketed. Good opportunities exist for operators of thrasher 
 and silo-filling outfits to do custom sawing during the winter. 
 
 For cutting large logs there are on the market several types of 
 power-driven drag-saws, such as are in common use in lumber opera- 
 tions in the Pacific Northwest. These machines, which are generally 
 operated by a 4-horsepower gasoline engine, can be carried from 
 log to log by two men, and cut logs up to 7 feet in diameter. It is 
 claimed that they can cut from 10 to 30 cords of firewood (soft- 
 woods) in 10 hours. 
 
Bui. 753, U. S. Dept. of Agriculture. 
 
 PLATE IV. 
 
 F 51620 
 
 FIG. I. SAWING BLUE GUM (EUCALYPTUS) WOOD WITH GASOLINE ENGINE. 
 
 Rate 1J to 2 cords per hour. Santa Fe Springs, Cal. 
 
 FIG. 2. LOAD OF HACKBERRY POLES ON PUBLIC SQUARE FOR SALE AT $2.50 
 PER LOAD, GALLATIN, TENN. 
 
Bui. 753, U. S. Dept. of Agriculture. 
 
 PLATE V. 
 
 FIG. I. Buzz SAW, POWER SPLITTER, AND CONVEYOR, SET UP AT 
 DOVER, MASS. 
 
 Photo by W. D. Clark. 
 
 FIG. 2. TABLE SAW AND SPLITTER OPERATED IN A MASSACHUSETTS 
 FARMER-S WOODSHED. 
 
 Photo by W. D. Clark. 
 
THE USE OF WOOD FOR FUEL. 13 
 
 These machines weigh from 150 to 200 pounds, and cost from 
 $170 to $200. They are probably not practical for ordinary cord- 
 wood operations where the trees are of comparatively small size. 
 The cost of sawing with power saws depends, of course, upon the 
 kind and size of wood sawed and upon the prevailing rate of wages. 
 With three or four-men crews, wages of 30 to 35 cents per hour, 
 and a cut of 16 to 20 cords per day, the average is as follows : 
 
 Cents per cord. 
 Labor 50 
 
 Gasoline 9 
 
 Oil 1 
 
 Depreciation, interest, etc .! 10 
 
 Total 70 
 
 Charges for custom work were from 50 cents to $1 per cord, de- 
 pending on the number of cuts and the kind of wood, but are now 
 between 75 cents and $1.50. 
 
 Splitting is still largely done by hand, often by the consumer in 
 his spare time, so that its cost is not an item to be considered in the 
 price he pays for wood. Although much larger amounts have been 
 split by expert axmen, an average man will seldom split more than 
 four cords of stove wood per day. The amount depends, of course, 
 on the species of wood. Some woods, such as birch, maple, and most 
 conifers, split very easily; others, such as elm, sycamore, gum, and 
 apple, are very hard to split. Most woods split more readily when 
 green or partly dry than when dry. Splitting machines are now 
 coming into more general use around woodyards where considerable 
 quantities of wood are handled. These machines are driven by the 
 same engines which run the cutting-up saws, and sawing and split- 
 ting are done at the same time. Two men with such a machine can 
 split the wood as it comes from the saw. By installing an automatic 
 carrier from saw to splitter one man can operate the latter. (See 
 fig. 1.) Splitting by machine should not cost more than 75 cents 
 per cord. By hand it costs around $1 per cord. 
 
 SEASONING. 
 
 The seasoning of wood for fuel is important, because dry wood 
 has a somewhat greater heating value than green wood, is much 
 more convenient to use, and is very much lighter in weight and 
 therefore can be handled at less cost. In general it seasons more 
 rapidly in the late spring and summer than during the remainder of 
 the year, and most slowly when cut in late winter. The fact that 
 checking is severe in summer does not matter, as this does not injure 
 fuel wood. 
 
 The method of stacking depends primarily upon the rapidity with 
 which it is desired to have the wood seasoned. A common practice 
 
14 
 
 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 Four foot wood 
 
 Building 
 
 is to pile the 4-foot lengths in compact piles resting on two bed pieces. 
 This does very well when the wood is to season for six months or 
 longer, but a different procedure must be adopted where more rapid 
 seasoning is desired. The most open form of pile is the so-called "log- 
 cabin " style. A pile which gives almost as good results without occu- 
 pying nearly as much space has alternate tiers resting on single sticks 
 
 at each end. There 
 
 Yard is ample ventilation 
 
 through the alter- 
 nate open layers. 
 
 It is very im- 
 portant for rapid 
 seasoning to place 
 the piles so that the 
 air will circulate 
 readily through 
 them. The ideal 
 place for this pur- 
 pose is an open field, 
 preferably on a hill- 
 top. The direction 
 toward which the 
 piles face is not 
 very important if 
 there is good air 
 circulation. The 
 best results will be 
 obtained in season- 
 ing if the piles are 
 so constructed as to 
 shed rain as much 
 as possible. 
 
 Cordwood of the 
 ordinary species 
 requires a period of 
 from 9 to 12 months 
 to season thor- 
 oughly, although the moisture content will be reduced to about 35 per 
 cent in three months' time, depending somewhat on the season of the 
 year. Wood of three months' seasoning has from 85 to 95 per cent 
 as much fuel value as wood of the same species thoroughly seasoned. 
 Even green wood has a heating value of 80 per cent or more of that 
 of dry wood. 
 
 TRANSPORTATION. 
 
 Ordinarily wood fuel is used within 5 to 10 miles of the locality 
 where it is produced, because its great bulk makes it expensive to ship. 
 
 _| 
 
 FIG. 1. Plan 
 
 of a retail wood dealer's 
 and splitting cordwood. 
 
 plant for sawing 
 
THE USE OF WOOD FOR FUEL. 
 
 15 
 
 It is commonly hauled from the woods to consumers or to dealers 
 in towns by team or auto trucks. The cost of hauling is determined, 
 of course, by the length of haul and by the amount that can be hauled 
 per trip, which depends upon the condition of the roads and upon 
 the species and dryness of the wood. The lowest cost for a given 
 operation can be attained by letting the wood season thoroughly 
 where it is cut and doing the hauling when the roads are best. 
 
 Where much of the haul must be over woods roads or other roads 
 which are normally in poor condition, winter hauling on sleds is 
 favored, since larger loads can be taken in this way. The chief disad- 
 vantage in depending on this method is the possibility of deep snow 
 interfering with the hauling. Where the wood can be skidded 
 out and piled beside good roads summer hauling by auto trucks is 
 by far the most economical way to get wood to market. 
 
 Costs for hauling wood by team may be put at about 50 to 75 cents 
 per cord per mile. The following tables, 1 which show approximate 
 costs of hauling northern hardwoods, may be taken as fairly typical 
 of the northern and eastern States : 
 
 TABLE 6. Team capacity per day for hauling various distances. 
 
 Sizes. 
 
 Number of cords per day per team. 
 
 Imile. 
 
 2 
 miles. 
 
 3 
 
 miles. 
 
 miles. 
 
 5 
 
 miles. 
 
 6 
 miles. 
 
 7 
 miles. 
 
 8 
 miles. 
 
 9 
 miles. 
 
 10 
 miles. 
 
 Long wood 
 
 7 
 5 
 4 
 
 6 
 4 
 3 
 
 5 
 3 
 
 2* 
 
 3 
 
 ? 
 
 2 
 2 
 11 
 
 if 
 
 il 
 
 1 
 
 1 
 1 
 1 
 
 1 
 1 
 1 
 
 1 
 1 
 
 1 
 
 4-foot wood 
 
 16-inch, stove wood . . 
 
 
 TABLE 7. Cost of team-hauling per short cord of 16-inch lengths, for different 
 distances and at different wage rates, including charge of 26 cents for 
 handling. 
 
 Distance from town (miles). 
 
 Trips 
 per 
 day. 
 
 Cords 
 hauled 
 per day. 
 
 Approximate cost per cord, with team 
 wage of 
 
 $4.50 per day. 
 
 $5 per day. 
 
 $6 per day. 
 
 5 and over 
 
 1 
 2 
 3 
 4 
 
 3-4 
 6-8 
 9-12 
 12-16 
 
 I1.40-J1.75 
 . 80- 1. 00 
 .65- .75 
 .55- .65 
 
 I1.50-J1.95 
 .90- 1.10 
 .65- .80 
 .55- .65 
 
 $1.75-J2.25 
 1.00-1.25 
 .75- .90 
 .65- .75 
 
 3 to 4. 
 
 2to3 
 
 Ito2.. 
 
 
 Although wood fuel can not as a general thing be economically 
 shipped to market, it is in certain instances practicable to do so, 
 especially in districts remote from the coal regions. Since shipment 
 by water is the cheapest method of transportation, towns on navi- 
 gable rivers and inlets along which are supplies of fuel wood are in 
 the best position to get wood at a reasonable cost. Washington, 
 
 1 " The Price of Fuel Wood,' 
 Michigan, Mar. 1, 1918. 
 
 by William K. Prudden, State fuel administrator of 
 
16 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 D. C., uses normally about 17,000 cords of wood fuel annually, most 
 of which is brought up the Potomac by sailboats with an average 
 capacity of 30 cords. 
 
 Freight rates on cordwood vary in different sections of the country 
 and on different railroads. At this time, on account of readjust- 
 ments, it is not possible to give very definite information on freight 
 rates. Recently the rate for distances of about 10 miles has averaged 
 about 50 to 60 cents, and has sometimes reached $1. Around 100 
 miles the rate has averaged $1.50 per cord, but has in some cases been 
 as low as $1 and in others as high as $2. 
 
 CAE CAPACITIES. 
 
 The minimum carload measurements on cordwood are as follows: 
 
 Number of 
 
 cords per car. 
 
 Dry. Green. 
 
 In box cars 34 feet 4 inches and less in length, inside measurement 12 12 
 In box cars over 34 feet 4 inches in length and 8 feet and over in 
 
 height, inside measurement . * 17 * 16 
 
 In box cars over 34 feet 4 inches in length and under 8 feet in height, 
 
 inside measurement 16 15 
 
 On flat or gondola cars 34 feet 4 inches and less in length 12 12 
 
 On flat or gondola cars between 36 and 34 feet 4 inches in length 18 16 
 
 WEIGHTS. 
 
 The following estimates are used for cordwood in shipments by 
 rail when actual weights can not be obtained : 
 
 Degree of seasoning. Pounds per cord. 
 
 Dry 3,650 
 
 Partly seasoned 4, 600 
 
 Green ^ 5,200 
 
 Mixed 4,600 
 
 Approximate weights per cord 2 of a number of the more important 
 fuel wood species are : 
 
 Green. Air dry. 
 Pounds. Pounds. 
 
 Ash, white '_ 4, 300 3, 800 
 
 Beech 5, 000 3, 900 
 
 Birch, yellow 5,100 4,000 
 
 Chestnut 4, 900 2, 700 
 
 Cottonwood 4,200 2, 500 
 
 Elm 4,400 3, 100 
 
 Hickory 5,700 4, 600 
 
 Maple, sugar 5, 000 3, 900 
 
 Maple, red 4, 700 3, 200 
 
 Oak, red 5,800 3,900 
 
 Oak, white 5,600 4,300 
 
 Willow 4, 600 2, 300 
 
 1 Where the wood is 16 inches or less in length, the capacities for these dimensions for 
 dry 'and green wood are 16 and 15 cords, respectively. 
 
 2 TJ. S. Department of Agriculture, Farmers' Bulletin 715, " Measuring and Marketing 
 Woodlot Products." 
 
THE USE OF WOOD FOR FUEL. 17 
 
 In loading and unloading from cars or boats one man can handle 
 from 7 to 10 cords of 4-foot wood per day and from 6 to 8 cords of 
 16-inch wood. 
 
 METHODS OF SELLING. 
 
 In spite of the fact that fuel wood is not transported any great dis- 
 tance or marketed on an extensive wholesale scale, some organiza- 
 tion is needed for its marketing and local distribution. In com- 
 munities where there are regular wood dealers the problem of bring- 
 ing the producer and consumer together is simple. Such men have, 
 of course, made a study of the problem and are better qualified 
 than anyone else to perform this service. Unfortunately, however, in 
 a great many communities the amount of cordwood sold has been 
 so small in the past that it has not been worth anyone's while to go 
 into the business of marketing firewood. In such communities the 
 usual practice has been for the woodlot owners to make a house-to- 
 house canvass with their loads. This is usually an expensive way of 
 marketing wood, for the producer spends a large amount of time in 
 finding a customer. A substitute for this canvass is the advertising 
 of wood either in the papers or by posters at public places. 
 
 The possibility of selling cordwood through coal or lumber dealers 
 deserves attention in every locality. This would have the advantage 
 of making possible a reduction in cost by using power saws at their 
 yards to cut the wood into stove lengths* A still better plan is for 
 communities to establish and control their own municipal wood yards, 
 at which producers can deliver wood and receive pay for it according 
 to a regular schedule of prices. 
 
 MUNICIPAL WOOD YABDS. 
 
 Municipal wood yards, war fuel companies, and similar organiza- 
 tions have been tried with fair success. Their field of usefulness 
 will doubtless be greatly increased as their need is more clearly appre- 
 ciated and their effectiveness becomes more apparent. Some organi- 
 zation is needed to keep alive the wood-fuel idea between seasons 
 and to see that wood is cut, even though it does not seem immediately 
 necessary. Every community should by means of a municipal wood 
 yard or otherwise get in a reserve of wood for the winter, sufficient 
 to insure its members against a fuel famine. One city in New Eng- 
 land has made plans to purchase 100,000 cords of wood as a fuel 
 reserve for the city. In one Southern State there are already some 
 30 municipal wood yards in operation, and plans are being made to 
 have one in practically every community in the State. If this is 
 necessary in the South it is much more urgent in the North, where 
 89354 18 3 
 
18 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 the winters are longer, and snow, especially in northern New Eng- 
 land, makes it practically impossible to get out much wood in the 
 depth of winter. 
 
 A yard established in 1917 at Durham, N. C., purchased 1,260 
 cords of wood at an average cost at the yard of $5 a cord. Wood 
 was delivered at an average cost to the consumer of $7. It came 
 from two sources a sawmill about 14 miles distant from which slabs 
 were shipped by rail, and a farmer's woodland from which cordwood 
 in 8- foot lengths was secured. The slabs were mostly green pine 
 of odd lengths, for which $2 per cord was charged f. o. b. cars. 
 Freight charges amounted to about 75 cents per cord. The coal and 
 wood yard is adjacent to the railroad tracks, and the wood was un- 
 loaded from the cars exactly where needed by the sawyers. The 
 wood from the farmers' woodlands near by was green pine and oak, 
 cut in 8-foot lengths and split in halves or quarters. The price was 
 $3.50 per cord piled in the woods. It was hauled from the woods to 
 the roadside by six county teams and there piled in a long rick, from 
 which it was loaded upon motor trucks. Three trucks were used, 
 each making four trips a day and carrying about 1 cord per ton of 
 rated capacity, so that the total daily Delivery was about 40 cords. 
 The cost of hauling was about $1 per cord ; it would have been less 
 if there had been better loading and unloading facilities. The dis- 
 tance was 2J to 3 miles. (See fig. 2.) 
 
 Cordwood was sold according to the cubic contents of the wagon 
 boxes, most of the wood being sold at the yard. The estimated cost of 
 sawing to stove length was 50 cents per cord on the yard. 
 
 MEASURING WOOD FUEL. 
 
 COEDS. 
 
 A standard cord of firewood is a pile 8 by 4 by 4 feet, which con- 
 tains 128 cubic feet of stacked wood. It is customary to pile green 
 wood 2 or 3 inches higher than 4 feet to allow for shrinkage and set- 
 tling as it dries. In measuring piles of wood the average dimensions 
 are taken. 
 
 A " running " cord or " face " cord, 8 feet long by 4 feet high and 
 12, 16, or 24 inches wide, according to the length to which it is cut 
 for use, is frequently called a cord in the market. 
 
 Though a cord contains 128 cubic feet the space occupied includes 
 air as well as wood. The actual solid contents of a cord is only about 
 70 per cent of this amount, or 90 cubic feet for wood of average size. 
 For small sticks, where the average diameter is 4 inches or less, there 
 are less than 80 cubic feet per cord; in the case of larger sticks 10 
 inches or over in diameter there may be as much as 100 cubic feet per 
 
THE USE OF WOOD FOR FUEL. 
 
 19 
 
 cord. Crooked, rough sticks can not be piled as closely as straight, 
 smooth sticks. Therefore there is less wood in a cord of crooked 
 sticks than in a cord of straight sticks. 
 
 STUM PAGE 
 Actual cwt if pur- 
 chased, otherwise 
 market value. 
 
 
 CUTTING-STACKING 
 
 Includes such items a a, 
 fllmg.bttckin. skidding 
 to road. and staking. 
 
 .Buct<in<? WillncoA* *S if 
 
 weed is hauledfe44M9tX 
 
 
 HAULING 
 
 Includes load ing.hau ling 
 by sled, wogort, truck, rait, 
 or boat.and unloading. 
 
 
 PROFIT 
 To producer. In cose of 
 
 farmer usually assert- 
 ed in stumpao,* or his 
 own wages 
 
 WOOD DEALER 
 
 COST OF WOOD 
 4-- FOOT OR SLED -LENGTH 
 DELIVERED TO 
 
 CONSUMER 
 
 MUNICIPAL OR 
 COMMUNITY 
 YARD 
 
 SAWING a SPLITTING 
 
 Includes labor oil, gas 
 etc.anH depreciation and 
 
 maintenance of equip men*. 
 
 SELLING a OVER HEAD 
 Includes advertising, rentals, 
 yard and office expenses 
 salaries, insurance, taxes* 
 
 DELIVERY 
 
 Includes loading, transport- 
 ation, unloading 
 
 INTEREST 
 On fiad investment 
 and working capital 
 
 SAWING a SPLITTJNG 
 
 Some as for dealer If consum- 
 er uses own machinery-mother - 
 wise price paid for custom work 
 if he works up wood by hand 
 in spar* time, -cost nominal 
 
 COST TO CONSUMER OF 
 WOOD READY TO BURN 
 
 5AWING 8 SPLITTING 
 Same as for deqter. 
 
 OVERHEAD 
 
 Includes such i ferns as 
 rentels yard and office e*- 
 pcnaes,aalerie3, insurance. 
 
 DELIVERY 
 5ome a* far dealer. 
 
 INTEREST 
 
 Same as for d* alar. 
 Rate may b lower. 
 
 FIG. 2. The elements of cost of wood fuel. 
 
 SELLING WOOD BY WEIGHT. 
 
 The great demand for fuel wood and the high prices during the 
 winter of 1917-18 brought out plainly the inadequacy of the cord 
 unit for measuring wood. The purchaser of fuel wood buys it not 
 for its bulk but for its heating value, which depends not upon the 
 
20 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 volume of wood but upon its weight. A pound of dry wood of one 
 species has about the same number of heat units as a pound of any 
 other species ; but a cord, assuming the same solid volume of wood in 
 each case (90 cubic feet), of basswood, for instance, yields but 12,- 
 600,000 British thermal units, while a cord of black locust yields 
 26,500,000 British thermal units. As a matter of fact, we can not 
 assume the same solid volume in two cords of wood ; a loosely piled 
 cord of small, round sticks may contain TO cubic feet or less, while a 
 closely piled cord of large split wood may contain over 100 cubic 
 feet. If it is locust, the first pile will yield 20,700,000 British thermal 
 units; the second, 29,600,000 units. If the first pile is basswood, it 
 will have a heating value of but 9,600,000 British thermal units. The 
 same cord of wood sawed up and repiled will be less than a cord in 
 bulk, though its heating value will not be reduced; thrown loosely 
 into a wagon box, it will fill up considerably more than 128 cubic 
 feet, but will not give off any more heat. 
 
 It is now the custom in most places to sell hardwoods and soft- 
 woods at slightly different prices because of recognized differences 
 in heating values. Branch wood is frequently sold at a lower price 
 than split body wood, as a result, partly at least, of a hazy recogni- 
 tion of the fact that there is less solid wood in a cord of the former. 
 Chestnut and hickory, however, are frequently mixed together as 
 hardwood, and sold at a given price regardless of whether 90 per cent 
 is chestnut, which would give the cord a low heating value, or 
 hickory, which would give it a high value. In many places even pine, 
 oak, and hickory are indiscriminately thrown together at a uniform 
 price, regardless of the proportion of each, so that one man may 
 for a given amount of money buy twice as much heat as another. 
 
 The practice prevalent in some sections of selling wood by the load 
 has afforded excellent opportunities for profiteering without the 
 knowledge of the purchaser. Few people would buy coal by the load 
 instead of by the ton, yet a given load of coal can not vary nearly 
 so much in heat value as a load of wood. 
 
 A better way to sell fuel wood would be by weight, which is entirely 
 independent of species, shape, or size of sticks, or of method of 
 piling, and is a very good measure of the fuel value of thoroughly 
 seasoned wood. Green wood, of course, varies considerably in water 
 content and therefore in fuel value per unit weight, and naturally 
 would be sold at a price different from that for dry wood. The 
 extreme difference in heat units per pound between green and dry 
 wood of any species is approximately 70 per cent of the dry value ; a 
 pound of green willow, for instance, is worth about one-third as much 
 as the same weight of dry wood. Green wood of most of the hard- 
 woods commonly used for fuel has about half the heating value of 
 dry wood of the same weight. 
 
THE USE OF WOOD FOE FUEL. 21 
 
 If weight instead of volume is adopted as the standard measure, it 
 will be necessary to fix certain standards as to time of seasoning of 
 wood offered for sale. This can easily be regulated in the case of 
 larger dealers, wood yards, and probably without serious difficulty 
 even for individual farmers, by use of a licensing system under which 
 a seller shall be required to certify under oath as to the date when 
 his wood was cut. 
 
 SELLING PRICES OF WOOD FUEL. 
 
 The Federal Government is without authority to fix prices on wood 
 fuel, as the act granting this power for coal and coke does not cover 
 wood. Some States, however, have gone ahead and set price limits 
 on the ground of public necessity in an emergency. While this may 
 be desirable in restricted areas, fixing of a maximum price on wood 
 is scarcely a good general policy, for two reasons : 
 
 First, the cost of producing wood fuel depends so much upon local 
 conditions that it would be hard to adjust prices equitably. 
 
 Second, price-fixing might tend to limit production to such an ex- 
 tent as to aggravate the crisis by decreasing the amount of wood fuel 
 available during the emergency. 
 
 The production of wood will be greatest if prices are left to regu- 
 late themselves, possibly with some local supervision. In all cases the 
 producer of wood should be considered entitled to a reasonable profit 
 on the costs of his operation. Some of the " war fuel companies " 
 which were formed during the fuel crisis in the winter of 1917-18 
 limited their profits to 6 per cent. Municipal yards as a rule sell at 
 cost. 
 
 MANUFACTURE OF SAWDUST BRIQUETS. 1 
 
 Practically all of the European machines use some kind of binder 
 mixed with the sawdust, or rely upon the resinous material in the 
 wood to hold the briquet together, but American and Canadian in- 
 ventors have apparently preferred mechanical binders. One com- 
 pany in Los Angeles is now building machines for the manufacture 
 of briquets of the wire-bound type, and a company in Vancouver 
 is perfecting machines for making the rope-core type. As far as can 
 be ascertained, both of these machines give promise of satisfactory 
 service under conditions of continuous operation. Another Van- 
 couver company is manufacturing machines for the production of 
 briquets composed of sawdust, coal dust, and binder in about the fol- 
 lowing proportions: Sawdust, 65 per cent; coal dust, 25 per cent; 
 binder (coal-tar pitch, petroleum refuse, or sulphite waste liquor), 
 
 1 " Briquetting of Sawdust on a Commercial Basis," R. Thelen, forest products labora- 
 tory, Madison, Wis., in Canada Lumberman and Woodworker, vol. 36, No. 5, pp. 39-40, 
 Mar. 15, 1016. 
 
22 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 jlcTper cent. These briquets are hard and firm and resemble coal 
 briquets in general appearance. 
 
 Although the various presses differ greatly in the details of their 
 construction, most of them work on the cy Under- and-plunger prin- 
 ciple, the plunger being driven by means of crank and connecting 
 rod or by some toggle-joint system of levers so designed that it is 
 capable of exerting a very great pressure at the end of the stroke. 
 Practically all of them also are automatically fed. In systems in 
 
 I which binders such as pitch are used and in those in which the resins 
 of the wood serve as binders, it is necessary to provide a long cooling 
 trough, sometimes as much as 150 feet in length for the finished 
 briquets. In systems using mechanical binders these cooling troughs 
 are unnecessary. 
 
 The cost of manufacturing briquets is not inconsiderable, conserva- 
 tive estimates placing the figures at not less than $3 a ton. The bulk 
 of the fuel prevents its economical shipment over long hauls. This 
 applies both to the finished briquet and to the raw sawdust. It is 
 believed that the ultimate consumer will have to pay at least $6 a 
 ton for the briquets to make the success of their manufacture assured. 
 
 MANUFACTURE OF CHARCOAL. 1 
 
 There are two chief methods of producing charcoal, the old kiln 
 method and the modern method of destructive distillation in a closed 
 retort. Most of the commercial charcoal is still made in the kiln, the 
 erection and operation of which costs, for the la'bor, about 60 cents 
 per ton of charcoal. 
 
 Wood loses 75 per cent in weight and 50 per cent in volume in char- 
 ring. Two cords of hardwood will yield 1 ton of charcoal ; 1 bushel 
 of charcoal, the selling unit, weighs about 25 pounds. 
 
 For making charcoal the wood should be thoroughly seasoned, 
 free from knots, and of but one species for each kiln charge. 
 
 The ground is prepared near water by leveling and hoeing the 
 soil, removing roots and stones, and raising the center of the circle 
 to be occupied by the kiln about 10 inches above its circumference. 
 The usual diameter of the circle is from 15 to 30 feet. The best soil 
 is loamy sand, which secures proper regulation of the draft. The 
 site should be protected from wind. 
 
 A " chimney " is erected by placing three or four poles of even 
 height at 1 foot distance from a central pole, and fastening them 
 around the central pole by withes. It is cylindrical if the kiln is 
 lighted from above, and pyramidal if the kiln is lighted from below ; 
 and is filled with inflammable substances, such as dried twigs, char- 
 coal, etc. 
 
 i Logging and Lumbering or Forest Utilization, pp. 167-168, a textbook for forest 
 schools, by C. A. Scbenck, director Biltmore Forest School. 
 
THE USE OF WOOD FOE FUEL. 23 
 
 The kiln proper is then constructed in a parabolic form. It con- 
 sists of two or more tiers of billets placed more or less vertically with 
 the bark turned outward, the big ends downward, the smallest pieces 
 near the chimney and near the circumference, the largest pieces 
 halfway between. These tiers are topped by a cap, consisting of 
 smaller billets placed sloping. If the chimney is cylindrical it 
 extends through the cap; if it is pyramidal it is closed by the cap. 
 In the latter case a lighting channel is left on the ground running 
 radially on the leeward side from the base of the pyramidal chimney 
 to the circumference. This channel, like the chimney, is filled with 
 inflammable material. All irregularities, interstices, and cracks 
 showing on the outside of the kiln are stuffed with small kindling. 
 The kiln is covered by two draft-proof layers so as to exclude the air ; 
 first the vegetable layer, one-fourth to three- fourths of a foot thick, 
 made of green branches, weeds, leaf mold, and moss; second, an 
 earth layer, 2 to 6 inches thick, consisting of loam, charcoal dust, etc. 
 If the kiln is lighted from below, a belt about 1 foot high running 
 around the circumference on the ground is left without the earth 
 cover until the fire is well started. The earth layer and the vegetable 
 layer are thoroughly joined by beating with a paddle. 
 
 The kiln is lighted early in the morning on a quiet day. The cylin- 
 drical chimney is closed on top as soon as the fire is well started in 
 the cap. The lighting channel, in the case of a pyramidal chimney, is 
 similarly closed. 
 
 The regulation of the fire and of the draft are the most important 
 functions of the attendant, who guides the fire evenly and gradually 
 from the cap down to the bottom. To check the draft the earth 
 cover is increased. To increase draft, holes of about 1 inch diameter 
 are made through the cover with the paddle reversed. If the wind 
 is strong all holes are closed and the earth cover is increased. Cracks 
 which form in the cover must be closed at once. The kiln may 
 explode if the cover is too heavy and the draft too strong. In dry 
 weather the kiln is continuously sprinkled. The color of smoke 
 escaping through the punctures indicates, by turning blue and trans- 
 parent, the completion of the charring process above the puncture. 
 The old punctures are then closed and another row of punctures is 
 made about 2 feet below the closed holes. 
 
 Refilling is required where dells are forming irregularly, while 
 the kiln gradually shrinks to one-half of its original volume. For 
 refilling, the cover over the dell is quickly removed, all holes having 
 been closed beforehand, and the dell is rapidly filled with new wood. 
 
 When the bottom holes show the proper color of smoke, the char- 
 ring process is completed. All holes are then closed, and the kiln 
 is allowed to cool. The duration of the charring process is from 6 to 
 
24 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 28 days, according to size of kiln. The contents vary from 4 to 60 
 cords. 
 
 Beginning at the leeward side the kiln is gradually uncovered. 
 The crust of earth, cut into fragments, is thrown on again. The 
 earth trickling down quenches the fire. After another 12 to 24 
 hours, preferably at night, the coal is taken out in patches or pockets, 
 slowly and carefully, so as to prevent the flames from breaking out. 
 Water must be at hand to quench incipient fires. 
 
 HOW TO USE WOOD FUEL. 
 
 Coal has been so generally used lately and furnaces and stoves have 
 become so adapted to its use that it seems impractical to many to 
 burn wood without going to great expense. Such is not usually the 
 case, as simple adjustments will allow wood to be used with coal- 
 burning equipment. The size of the firebox, of course, gives the 
 greatest difficulty, since in many cases it may make it necessary to 
 cut the wood into very small blocks. This trouble, however, is not in- 
 surmountable and is not so expensive as it might seem. The matter 
 of adjusting the drafts and arranging the grates is simple. 
 
 Following are a number of practical directions which are largely 
 the result of experience in changing from coal to wood fuel. 
 
 BURNING WOOD IN STOVES. 
 
 A coal-burning stove can be converted into a wood -burning stove 
 by removing the fire brick and substituting lighter bricks at a cost 
 of about $1.25. Most country cook stoves can burn wood with little 
 trouble. If a stove grate is too coarse for wood, a sheet-iron cover over 
 a good part of the surface will make it suitable, or a few fire bricks 
 can be used. Wood grates made in two pieces are sold which can be 
 inserted through the fire door and placed on top of the regular 
 grate. 
 
 BURNING WOOD IN FURNACES. 1 
 
 Furnaces are built especially for burning wood in 3 or 4 foot 
 lengths. Short lengths, of course, can readily be burned in an ordi- 
 nary coal furnace or in a box stove, though this is rather wasteful of 
 fuel. Many furnace manufacturers, however, make a special wood 
 grate for use in their furnaces. One advantage in burning wood is 
 that on moderately cool days the furnace can be run at a lower ebb 
 than when coal is used, consuming only enough fuel to remove the 
 chill. When wood is used in a round pot furnace care should be 
 taken to have each piece lie flat. 
 
 Adapted from a bulletin by E. H. Lockwood, published by P. B. Noyes, director of 
 conservation, U. S. Fuel Administration, Washington, D. C. 
 
THE USE OF WOOD FOR FUEL. 25 
 
 USING WOOD ONLY. 
 
 There are difficulties in burning wood as a substitute for coal in a 
 steam, hot-water, or warm-air furnace, but it can be done with a 
 fair degree of success, especially in mild weather. 
 
 The best form of wood is short blocks, from 8 to 12 inches long, 
 preferably of hardwood, although mixed hard and soft, or even 
 softwood alone, can be used. Medium-sized pieces, such as those 
 found in ordinary cord wood, are suitable, although larger pieces 
 keep the fire better. 
 
 The best method of firing is to keep the furnace full of wood 
 packed close with a moderate draft to give the desired amount of 
 heat. As the wood burns more should be added in order to keep the 
 deep bed of burning fuel, which is most economical. 
 
 Banking the fire at night requires an extra supply of the largest 
 blocks and special attention to closing the dampers tight. Experience 
 will show the best way, but it can be done with success in most 
 furnaces. 
 
 It is not necessary to buy new grates for burning wood, although 
 the ordinary coal grate is not well adapted for wood. A good way 
 is to add a little nut coal to the fire at the start, allowing the layer 
 of coal ashes to remain on the grates. Air required for combustion 
 can pass through the ash layer, which can be shaken lightly without 
 much loss of ashes. The larger the fire box the better the results. 
 
 A furnace designed for burning coal may be made into what is 
 known as a "Wilson heater," which is one of the most economical 
 stoves for wood burning, by removing the grate bars and laying 
 fire brick on the floor of the ash pit. A wood fire is then built on 
 the fire brick, and the ash pit door is kept tightly closed and the 
 ventilator in the fuel door open. A wood fire can in this way be 
 made to burn very slowly. 
 
 USING A COMBINATION OF WOOD AND COAL. 
 
 The simplest way to use wood in a coal furnace, and the most effec- 
 tive in producing heat, is to combine it with coal. The method of 
 firing is to place blocks of wood on the fire to about the level of the 
 fire door, instead of shoveling on coal in the usual way, then add 
 coal on the top, which will fill the crevices between the wood, mak- 
 ing a level fuel bed with coal on top.. A fuel charge of this kind 
 will produce good heat but will not last as long as a fire pot full of 
 coal, hence more frequent attention is needed. 
 
 From 25 to 50 per cent of the coal ordinarily used can be saved by 
 substitution of wood in this way. Any kind or size of wood can 
 be used that will go into the fire pot, and will burn with good 
 efficiency when surrounded with coal. 
 
26 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 Any size of coal or coke can be used, but the small sizes fill in best 
 between the chinks in the wood. Buckwheat coal can be burned 
 successfully in this way, and its low price will help to offset the 
 higher price of block wood, making an economical combination. 
 
 CAUTION. When burning the small sizes of coal take care to 
 avoid gas explosions by always leaving a flame burning on some part 
 of the fire; in other words, do not cover the whole fire with fresh 
 fuel at one time. 
 
 BURNING WOOD IN FIREPLACES. 
 
 Where a fireplace is available wood can be used to good advan- 
 tage, affording both heat and ventilation. Its value is to supple- 
 ment a furnace, although it may replace the furnace in fall and 
 spring with decided economy. 
 
 It is not generally realized that a wood fire can be kept burning 
 night and day in a fireplace with very little attention and with small 
 consumption of wood. One user reports continuous use of a fire- 
 place in this way for over a month, with dry chestnut wood, where 
 the amount of ashes formed by a month's use was not enough to 
 require removal. 
 
 The secret of fireplace management is a plentiful supply of ashes, 
 kept at the level of the andirons. As the blocks burn, an accumu- 
 lation of glowing charcoal forms in the ashes. This keeps on burn- 
 ing slowly and assists in igniting the fresh blocks on the andirons. 
 A pocket may be formed in the ashes into which the hot charcoal 
 may fall, forming a heat storage. Two or three blocks on the and- 
 irons with the hot charcoal in the ashes will form an excellent fire. 
 
 To check the fire, ashes are shoveled over one or more of the blocks, 
 covering lightly all the burning wood. This will not put out the 
 fire; it will only check the rate of burning, so that red charcoal will 
 be found when the ashes are removed for addition of fresh fuel. 
 
 Fireplace wood is usually cut in longer lengths than stove wood, 
 but the ordinary 16-inch stove length is convenient. Any kind of 
 wood can be used, provided it is dry and seasoned. 
 
 A banked fire will keep 10 or 12 hours and will send some heat 
 from the hot bricks all the time. A well-managed fireplace will be 
 found a great addition to the heating system in any residence. 
 
 INDUSTRIAL USE OF WOOD FUEL, 
 
 Wood is very generally used for fuel by sawmills and wood- 
 working plants. For this purpose it is burned in the form of slabs, 
 4 feet or so long, or is cut up into " hog " fuel and shoveled or fed 
 automatically into the fire box. In these cases wood fuel is a by- 
 product which would have to be disposed of at some cost if not 
 burned for fuel, so that its use is economical. It is seldom economical 
 
THE USE OF WOOD FOR FUEL. 27 
 
 to buy firewood for industrial use, except to keep a plant running 
 when other fuel can not be had. 
 
 EFFICIENCY OF WOOD FUEL. 
 THEORETICAL HEATING VALUES OF WOOD. 
 
 The heating power or fuel value of a given volume of dry wood 
 is in direct ratio to its specific gravity. By specific gravity is meant 
 the ratio of the weight of a given volume of wood to that of an 
 equal volume of water. Water weighs a little over 62 pounds per 
 cubic foot, and wood, which weighs 31 pounds per cubic foot when 
 perfectly dry, is said to have a specific gravity of 0.50, and so on for 
 other weights. 
 
 In theory equal weights of wood ^ubstance will give the same 
 amount of heat regardless of the species. In other words, a hundred 
 pounds of absolutely dry cottonwood should furnish as much heat 
 as a hundred pounds of hickory. In reality the varying forms of 
 tissue found in the different species, the addition of resin, gums, 
 tannin, oils, and pigments, as well as water present in varying 
 amounts, cause different woods to have different heating values. 
 The presence of rosin in wood increases the heating power mate- 
 rially, the results of numerous tests showing a difference ranging 
 up to 12 per cent or more. 
 
 The composition of absolutely dry wood is approximately as 
 follows: Carbon, 49 per cent; oxygen, 44 per cent; hydrogen, 6 per 
 cent; ash, 1 per cent. 
 
 This is fairly constant for all species, except as modified by infil- 
 trations, such as gums, pigments, resins, tannin, etc., so that equal 
 weights of dry nonresinous woods give off practically the same 
 amount of heat in burning. A pound of thoroughly dry wood will 
 furnish under good conditions between 7,000 and 9,000 British ther- 
 mal units. A pound of good coal will furnish from 12,000 to 14,000 
 units, making dry wood about 57 per cent as efficient as coal. 
 
 When wood containing water is burned part of the heat the wood 
 is capable of yielding is taken up in raising the water to the boiling 
 point and converting it into steam. The steam must then be raised 
 to the temperature of the flue gases. All this heat is lost, and the 
 greater the amount of water present the more heat is carried off. 
 The water in green wood often makes up half of the total weight, 
 especially in sapwood. After such wood is thoroughly air-seasoned 
 there would remain about 20 per cent of water. If the wood is kiln- 
 dried, from 2 to 5 per cent of water remains, and if it is exposed to 
 the air, this percentage is increased by absorption (hygroscopically) 
 from 10 to 15 per cent, depending upon the humidity. 
 
 A hundredweight of wood as sold on the market contains about 25 
 pounds of water, 74 pounds of wood substance, and 1 pound of ash. 
 
28 
 
 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 These 74 pounds are made up of 37 pounds of carbon, 4.4 pounds of 
 hydrogen, and 32 pounds of oxygen. The oxygen combines with 
 the hydrogen in the proportion of 8 to 1, producing 36 pounds of 
 water and leaving four-tenths of a pound of hydrogen to produce 
 heat. The total amount of water to be evaporated becomes 25 plus 
 36, or 61 pounds.; the amount of wood substance left available for 
 heat production is 37.4 pounds out of the original 100 pounds. 
 
 It is evident that the greater the proportion of water the less the 
 amount of available heat. Only about one-half of the weight of 
 wood substances produces heat, while every pound of water com- 
 bined in the wood requires 1,108 units of heat to evaporate it, from 
 ordinary room temperature (70 F.). Hence under the most favor- 
 able circumstances the heating efficiency of a pound of wood con- 
 taining 25 per cent moisture will be less than that of dry wood not 
 only by the 2,000 units representing the weight of wood replaced 
 by water, but also by one-fourth of 1,108 units, or 277 units, so that 
 its heating value is but 5,723 units instead of 8,000, or 72 per cent of 
 that of a pound of dry wood. On the other hand, if we take the 
 pound of wet wood and dry it out absolutely, so that it weighs 
 three-fourths of a pound, it will have 6,000 heat units, an increase in 
 heating value due to drying of only about 5 per cent. 
 
 COMPARATIVE VALUES OF DIFFERENT WOODS. 
 
 The comparative values of fuel of various species of American 
 woods are shown in Table 8. These values are necessarily some- 
 what approximate but afford a good basis for comparison of the 
 different species. 
 
 TABLE 8. Heat values of cordwood, based on Forest Products Laboratory 
 (Madison, Wis.), weights for oven-dry, air-dry, and green woods and assum- 
 ing 7,350 B. t. u. available per pound of dry wood with flue gases at 300 F. 
 
 Species. 
 
 Available heat units 
 per cord of 90 solid 
 cubic feet (in mil- 
 lions B. t. u.). 
 
 Percent of short- 
 ton coal value. 
 
 Air-dry. 
 
 Green. 
 
 Air-dry. 
 
 Green. 
 
 Alder red. (A oregona) 
 
 14.8 
 20.7 
 18.5 
 21.3 
 20.6 
 19.7 
 19.4 
 20.5 
 23.0 
 14.1 
 14.2 
 12.6 
 20.9 
 18.2 
 23.3 
 20.9 
 17.5 
 17.5 
 
 13.0 
 20.0 
 16.5 
 20.7 
 19.6 
 19.0 
 18.2 
 19.9 
 22.4 
 12.1 
 12.4 
 11.0 
 19.7 
 16.7 
 21.9 
 19.4 
 16.1 
 15.7 
 
 57 
 80 
 71 
 82 
 79 
 76 
 75 
 79 
 88 
 54 
 55 
 48 
 80 
 70 
 90 
 80 
 68 
 68 
 
 50 
 77 
 64 
 80 
 75 
 73 
 70 
 77 
 86 
 47 
 48 
 42 
 76 
 64 
 84 
 75 
 62 
 60 
 
 Ash biltmore (F biltmoreana) 
 
 black (F nigra) 
 
 Blue (F quadrangulata) 
 
 Green (F lanceolata). 
 
 Oregon (F oregona) 
 
 Pumpkin (F profunda). . . 
 
 "WTiite (F americana) 
 
 White (second growth) 
 
 Aspen (F tremuloides) 
 
 Largetooth (P grandidentata) 
 
 Basswood (T americana) - 
 
 Beech (F atropunicea) 
 
 Birch, paper ( B papyrif era) .... 
 
 Sweet (B lenta) 
 
 Yellow (B. lutea) ... 
 
 Gray (B populifolia) . . .. 
 
 Red (B. nigra)i... 
 
 1 Gray and red birch estimated. 
 
THE USE OF WOOD FOB FUEL. 29 
 
 TABLE 8. Heat lvalues of cordwood, based on Madison Laboratory iceights. Con. 
 
 Species. 
 
 Available heat units 
 per cord of 90 solid 
 cubic feet (in mil- 
 lions B. t. u.). 
 
 Per cent of short- 
 ton. coal value. 
 
 Air-dry. 
 
 Green. 
 
 Air-dry 
 
 Green. 
 
 Buckeye yellow (A octandra) 
 
 12.8 
 20.2 
 14.3 
 17.2 
 18.5 
 14.2 
 15.6 
 12.8 
 15.0 
 17.8 
 25.2 
 22.4 
 18.4 
 22.6 
 19.1 
 17.7 
 18.5 
 24.1 
 18.5 
 17.7 
 19.1 
 24.8 
 24.8 
 24.2 
 25.4 
 22.0 
 24.2 
 25.9 
 25.4 
 24.5 
 19.6 
 24.7 
 20.7 
 24.9 
 26.5 
 24.5 
 22.6 
 18.4 
 17.7 
 19.1 
 17.9 
 21.8 
 22.6 
 20.5 
 27.5 
 22.4 
 24.0 
 21.7 
 25.3 
 24.0 
 21.7 
 20.4 
 24.0 
 25.1 
 21.7 
 21.7 
 23.9 
 21.2 
 22.0 
 30.8 
 25.0 
 19-5 
 17.2 
 26.1 
 17.2 
 19.9 
 17.9 
 18.5 
 18.5 
 15.5 
 20.8 
 13.5 
 15.5 
 21.8 
 15.1 
 
 10.1 
 18.6 
 12.2 
 13.9 
 17.3 
 13.5 
 12.9 
 10.5 
 12-7 
 16.0 
 23.7 
 21.4 
 15.2 
 21.5 
 17.1 
 15.8 
 17.4 
 22.4 
 16.2 
 16.0 
 17.7 
 23.1 
 23.1 
 22.2 
 23.8 
 19.9 
 . 22.5 
 24.7 
 23.8 
 21.6 
 17.8 
 23.5 
 18.8 
 23.2 
 25.4 
 22 5 
 20.9 
 15.5 
 16.3 
 17.6 
 16.4 
 20.4 
 20.8 
 17.7 
 25.7 
 20.7 
 22.1 
 19.6 
 23.4 
 22.2 
 19.6 
 18.1 
 21.9 
 23.4 
 19.7 
 19.4 
 22.4 
 19.3 
 19.7 
 30.1 
 24.0 
 17.2 
 15.7 
 25.2 
 15.7* 
 18.2 
 16.9 
 17.1 
 16.6 
 13.8 
 18.6 
 10.9 
 13.4 
 20.1 
 13.9 
 
 49 
 78 
 55 
 66 
 71 
 55 
 60 
 49 
 58 
 68 
 97 
 86 
 71 
 87 
 73 
 68 
 71 
 93 
 71 
 - 68 
 73 
 95 
 95 
 93 
 98 
 85 
 93 
 100 
 98 
 94 
 75 
 95 
 80 
 96 
 102 
 94 
 87 
 71 
 68 
 73 
 69 
 84 
 87 
 79 
 106 
 86 
 92 
 83 
 97 
 92 
 83 
 78 
 92 
 97 
 83 
 83 
 92 
 82 
 85 
 118 
 96 
 75 
 66 
 100 
 66 
 77 
 69 
 71 
 71 
 60 
 80 
 52 
 60 
 84 
 58 
 
 39 
 72 
 47 
 53 
 67 
 52 
 50 
 40 
 49 
 62 
 91 
 82 
 58 
 83 
 66 
 61 
 67 
 86 
 62 
 62 
 68 
 89 
 89 
 86 
 92 
 77 
 87 
 95 
 92 
 83 
 68 
 90 
 72 
 89 
 98 
 87 
 80 
 60 
 63 
 68 
 63 
 78 
 80 
 68 
 99 
 80 
 85 
 75 
 90 
 85 
 75 
 70 
 84 
 90 
 76 
 75 
 86- 
 74 
 76 
 116 
 92 
 65 
 60 
 97 
 60 
 70 
 65 
 66 
 64 
 53 
 72 
 42 
 52 
 77 
 53 
 
 Buckthorn ( R purshiana) 
 
 Butternut ( J cinerea) 
 
 
 Cherry black (P serotina) 
 
 Wi'ld red (P pennsylvanica) 
 
 Chestnut (C dentata) . 
 
 Cotton wood (P trichocarpa) 
 
 Cotton wood (P deltoides) 
 
 Cucumber (M acuminata) 
 
 Dogwood flowering (C florida) 
 
 Western (C. nuttallii) 
 
 Elder, pale (S glauca) 
 
 Elm cork (U racemosa) 
 
 Slippery (U pubescens) .. 
 
 White (U americana) 
 
 Gum, black (N. silvatica) 
 
 Blue (Eu globulus) 
 
 Cotton (N. aquatica) . . 
 
 Red (L styraciflua) 
 
 Hackberry (C occidentalis) . . . 
 
 Haw, pear (C tomentosa) 
 
 Hickory, shellbark (H, laeiniosa),. 
 
 Bitternut (H minima) 
 
 Mockernut (H. alba) . . 
 
 Nutmeg (H myristicae formis) . 
 
 Pecan (H. pecan) 
 
 Pignut (H. glabra) 
 
 Shagbark (H. ovata) . . 
 
 Water (H. aquatica) 
 
 Holly (I. opaca) 
 
 Hornbeam (O virginiana) . . 
 
 Laurel, California (U. californica) 
 
 Mountain (K. latifolia) .... 
 
 Locust, black (R. pseudacacia).. 
 
 Honey (G. triacanthos) 
 
 Mondrona (A. menziesii) 
 
 Magnolia, evergreen (M. foetida) . . . 
 
 Maple, Oregon (A. macrophyllum) 
 
 Red (A. rubrum) 
 
 Silver (A. saccharinum) 
 
 Sugar (A. saccharum). 
 
 Oak, bur (Q. macrocarpa) 
 
 California, black (Q. californica) 
 
 Canyon live ( Q. chrysolepis) 
 
 Chestnut (Q. prinus) 
 
 Cow (Q. michauxii) 
 
 Laurel (Q. laurifolia) 
 
 Pacific post (Q. garryana) 
 
 Post (Q. minor).... 
 
 Red(Q.rubra).... 
 
 Spanish ( Q. digitata) 
 
 Spanish (Q. pagodaefolia) 
 
 Swamp white (Q. platanoides) . . 
 
 Water (Q. nigra). . 
 
 Tanbark (Q. densiflora) .... 
 
 White (Q. alba)... 
 
 Willow (Q. phellos) 
 
 Yellow, black (Q. velutina).. 
 
 Osage, orange (Tox. pomiferum) . 
 
 Persimmon (D. virginiana) 
 
 Rhododendron (R. maximum).. 
 
 Sassafras (S . sassafras) 
 
 Service berry (A. canadensis) 
 
 Silverbell (Mohrodendron carolinum) 
 
 Sourwood (Oxydendrum arboreum)... 
 
 Sumac (R. hirta) 
 
 Sugarberry (Celtis mississippiensis) 
 
 Sycamore (P. occidentalis) 
 
 Umbrella (Mag. fraseri) 
 
 Walnut, black (J. nigra) 
 
 Willow, black ( S. nigra) 
 
 Western, black (S . lasiandra) 
 
 Witch hazel (H. virginiana) 
 
 Yellow poplar (L. tulipifera) 
 
30 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 TABLE 8. Heat values of cordwood, based on Madison Laboratory weights. Con. 
 
 Species. 
 
 Available heat units 
 per cord of 90 solid 
 cubic feet (in mil- 
 lions B. t. u.). 
 
 Per cent of short- 
 ton coal value. 
 
 Air-dry. 
 
 Green. 
 
 Air-dry 
 
 Green. 
 
 Cedar, incense (L. decurrens) 
 
 14.5 
 16.3 
 12.1 
 11.3 
 16.4 
 15.8 
 17.7 
 15.6 
 12.0 
 15.1 
 13.5 
 15.1 
 14.3 
 14.3 
 17.2 
 15.0 
 15.0 
 19.3 
 19.1 
 22.4 
 15.7 
 15.0 
 ' 19.9 
 15.0 
 22.0 
 17.8 
 18.5 
 20.0 
 19.9 
 14.3 
 19.3 
 15.7 
 15.0 
 14.2 
 11.9 
 15.0 
 13.5 
 14.1 
 24.4 
 14.3 
 
 12.3 
 15.5 
 11.7 
 10.7 
 14.5 
 15.1 
 17.3 
 15.1 
 11.5 
 12.9 
 11.5 
 13.3 
 13.7 
 11.1 
 15.7 
 12.8 
 13.5 
 17.9 
 18.1 
 21.6 
 13.4 
 12.9 
 18.1 
 13.8 
 21.1 
 16.8 
 16.4 
 18.7 
 18.5 
 11.7 
 17.2 
 14.6 
 13.1 
 12.9 
 10.5 
 14.2 
 12.7 
 13.5 
 23.2 
 12.9 
 
 56 
 63 
 47 
 43 
 63 
 61 
 68 
 60 
 46 
 58 
 52 
 58 
 55 
 55 
 66 
 58 
 58 
 74 
 73 
 86 
 60 
 58 
 77 
 58 
 85 
 68 
 71 
 77 
 77 
 55 
 74 
 60 
 58 
 55 
 46 
 58 
 52 
 54 
 94 
 55 
 
 47 
 60 
 45 
 41 
 56 
 58 
 67 
 58 
 44 
 50 
 46 
 51 
 53 
 43 
 60 
 49 
 52 
 69 
 70 
 83 
 52 
 50 
 70 
 53 
 81 
 65 
 63 
 72 
 71 
 45 
 66 
 56 
 50 
 50 
 40 
 55 
 49 
 52 
 89 
 50 
 
 Port orford (C. lawsoniana) 
 
 Western red (T plicata) 
 
 White (T. occidentilis) 
 
 Cypress, bald (T. distichum) 
 
 Yellow (C. nootkatensis) 
 
 Douglas fir, Pacific coast (P. taxifolia) 
 
 Rocky Mountains 
 
 Fir. alpine (A. lasiocarpa) .... 
 
 Amabilis (A. amabilis) 
 
 Balsam (A. balsamea) 
 
 Lowland white (A. grandis) 
 
 Noble (A. nobilis) 
 
 Silver, white (A. concolor) 
 
 Hemlock, black (T . mertensiana) 
 
 Eastern (T. canadensis) 
 
 Western (T. heterophylla) 
 
 Larch, western (L. occidentalis) 
 
 Eastern (L. americana) 
 
 Pine, Cuban, slash (P. heterophylla) 
 
 Jack (P. divaricata) 
 
 Jeffrey (P jeffreyi) 
 
 Loblolly ( P . taeda) . . 
 
 Lodgepole (P contorta) 
 
 Longleaf (P. palustris).. . 
 
 Norway (P. resinoea) 
 
 Pitch(P.rigida) 
 
 Pond (P . serotina) . . . 
 
 Shortleaf(P.echinata) 
 
 Sugar (P . lambertiana) , 
 
 Table Mountain (P. pungens) 
 
 Western white (P. monticola) 
 
 Western yellow (P. ponderosa) 
 
 White (P. strobus) 
 
 Spruce, Engelmann (P. engelmanni) 
 
 Red (P rubra) 
 
 Sitka (P.sitchensis) ... 
 
 White (P. canadensis) 
 
 Yew, western (T. brevifolia) 
 
 Redwood (S. sempervirens) 
 
 
 Coal, long ton (2,240 pounds) . . . 
 
 29.1 
 26.0 
 
 
 
 
 Short ton (2 000 pounds) 
 
 
 
 
 
 
 
 
 NOTE. Values given for resinous woods are low, since resin adds to heating value; for instance, dry 
 Iqngleaf pine with 20per cent resin has a value of approximately 26,400,000 B . t. u., instead of the 22,000,000 
 given in the table. The amount of bark in a cord of wood also affects the heating value; for instance, bark 
 of birch, Douglas fir, western yellow pine, and others has a higher value than the wood. Much of the 
 theoretical value of both wood and coatis lost in use. While anthracite and soft coal have about the same 
 theoretical value, only from 70 to 75 per cent Of this value is realized with anthracite and from 60 to 65 per 
 cent with bituminous coal . Values decrease as temperature of flue gases increases . To get values for wood 
 only partly seasoned it may be assumed that in most cases it will be about half seasoned in three months, 
 two-thirds seasoned in six months, and entirely air-dry in about a year. 
 
 It may be seen from this table that the heating power of a given 
 quantity of green wood is not so very much below that of the same 
 wood after it has been dried. The choice of wood for fuel does not, 
 however, depend entirely upon its calorific power ; other factors, such 
 as freedom from smoke, completeness of combustion, and rapidity of 
 burning, play a very important part. Green wood is not only much 
 heavier to handle but it is also harder to ignite and to keep burning, 
 unless mixed with dry wood or with coal, and makes more smoke. For 
 a slow fire green wood or a mixture of green and dry wood is 
 often more satisfactory than dry wood alone, since the latter burns 
 up rapidly and much of its heat escapes up the pipe. 
 
THE USE OF WOOD FOB FUEL. 
 
 31 
 
 Heating values of different parts of the same tree may vary con- 
 siderably, because of differences in moisture content, proportion of 
 bark to wood, and other factors. Tests made by the department of 
 forestry of the Michigan Agricultural ^College gave the following 
 results : 
 
 Position. 
 
 Moisture. 
 
 Dry 
 matter. 
 
 British thermal units 
 (per pound). 
 
 Green 
 wood. 
 
 Dried 
 wood. 
 
 Beech sap near stump . 
 
 Percent. 
 40.2 
 25.2 
 44.1 
 36.2 
 36.1 
 32.8 
 30.8 
 35.7 
 
 Per cent. 
 59.8 
 74.7 
 55.9 
 63.8 
 63.9 
 67.2 
 69.2 
 64.3 
 
 5,534.4 
 7,258.0 
 5,086.6 
 5, 888. 4 
 5,581.9 
 5,870.8 
 6,099.1 
 5,817.2 
 
 9, 253. 5 
 
 9,718.5 
 9,098.5 
 9. 227. 1 
 8,735.8 
 8, 735. 8 
 8, 813. 3 
 9,045.8 
 
 Beech' heart near stump 
 
 Beech' sap near top * 
 
 Beech limb 2 inches diameter 
 
 Maple sap near stump 
 
 Maple heart near stump ..... . 
 
 
 Maple limb 2 inches diameter 
 
 
 In a number of species the bark has a higher heating value than 
 other parts of the tree. In the Northwest, Douglas fir bark is often 
 a principal source of fuel in firing donkey engines. The bark of 
 shagbark hickory has a high fuel value and burns with intense heat, 
 but with much crackling. In the case of many woods, such as the 
 cedars, the bark has a comparatively low fuel value and leaves a large 
 proportion of ash. 
 
 Root wood is little used for fuel, mainly because of the difficulty in 
 getting it and its awkward form. It is interesting to note, how- 
 ever, that the roots of mesquite are capable of producing more heat 
 than the average butt cut, and are commonly dug up for firewood 
 where other wood is very scarce. Very often mesquite roots are so 
 much more developed than the rest of the tree that the name " under- 
 ground forests" has been applied to stands of the timber in semi- 
 arid regions. 
 
 The rapidity of burning may be important where quick heating is 
 desired. As a general rule the softwoods burn more readily than the 
 hardwoods, while the lighter hardwoods burn more readily than the 
 heavier ones. The pines, for instance, give a quicker, hotter fire and 
 are consumed in a shorter time than birch, but birch gives a more in- 
 tense flame than oak. On the other hand, the oaks give a more steady 
 heat. Less than 5 per cent of the wood used as fuel is consumed in 
 the industries, the remainder, or more than 95 per cent, being used 
 for domestic purposes, where such qualities as ease of ignition, ra- 
 pidity of combustion, freedom from smoke, uniform heating, or 
 quickness of burning, depending on the particular results desired, are 
 more important than calorific value. A few species, such as chestnut, 
 butternut, tamarack, and spruce, are in ill favor for open fires be- 
 cause they throw off sparks. 
 
32 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 Another point worth bearing in mind in connection with the burn- 
 ing of wood in place of coal is the difference in the amount of ash 
 produced. A cord of hardwood will make only about 60 pounds of 
 ashes, while a ton of hard (foal will make from 200 to 300 pounds. 1 
 
 A pound of wood briquet, irrespective of species, should have 
 about* the same heat value as dry wood, probably a little higher, on 
 account of the heat value of the organic binder (if one is used), 
 which may have a greater unit heat value than wood and thus raise 
 the average slightly. If the resins in the wood are used as binders 
 the same result may be expected. In comparing briquets with cord- 
 wood or stove wood it must be remembered that the briquet is usually 
 drier and will therefore generate more heat per pound of material 
 than will wood. 
 
 In actual use wood fuel does not always show up as favorably in 
 comparison with coal as the above heat values would indicate. This is 
 probably due to the fact that it is not the actual heat-producing 
 power of the fuels that is compared but the efficiency of the appara- 
 tus for utilizing the heat. Wood requires about one-third more grate 
 surface and two-thirds more cubical space than coal for generating 
 an equal amount of steam. 
 
 In logging engines a ton of good grade bituminous coal is consid- 
 ered equivalent to a cord and a half of air-dry oak or two cords of 
 softwood. Two and a half cords of pine knots (about 125 cubic 
 feet) are thought to furnish about the same amount of steam as 1 
 ton of southern soft coal. For general calculations for stationary 
 engines 1 ton of coal is considered equivalent to 2 cords of wood, or 
 1 pound of coal to 2J pounds of wood. During the winter of 1917-18 
 
 1 Since potash is now greatly in demand, the quantity which may be obtained from 
 wood ash is worth consideration. 
 
 The quantity of ashes obtained from a cord of wood varies with the conditions under 
 which it is burned. About 30 cords of hardwood produce a ton of ashes equal in quan- 
 tity to the Canadian wood ashes of commerce ; but the same quantity of wood consumed 
 as fuel in a cook stove or other small, closed burner would be far more completely reduced 
 and would produce only about one-third to two-thirds of a ton of ash. On the other 
 hand, commercial hardwood ashes contain only 5 per cent of the valuable fertilizer 
 potash, whereas stove ashes contain from 10 to 15 per cent, so that the amount of potash 
 to be had from a cord of wood is about the same however the wood is burned and re- 
 gardless of the bulk of the resulting ash. Softwood ashes contain on an average about 
 one-third less potash than hardwood ashes, and the quantity of ash obtained from 
 softwoods is less than from the same bulk of hardwood. The present price of potash, 
 about 25 cents a pound, or $500 a ton, almost prohibits its use in fertilizers. 
 
 It is important always to keep wood ashes under cover, as they leach rapidly if allowed 
 to become damp. New ashes should be allowed to cool before they are dumped on the 
 ash heap. 
 
 It is estimated that the ashes from a cord of northern hardwoods will furnish about 
 20 pounds of lime, more than 3 pounds of potash, and a half pound of phosphoric acid, 
 and that they have a value at present prices of about $1. 
 
 H. J. Wilder, agriculturist of U. S. Department of Agriculture (letter to Mr. A. F. 
 Hawes, July 18, 1918) : Hardwood ashes which have not been wet analyze about 5 per 
 cent potash, 30 to 35 per cent lime, both in desirable forms. Potash contents of soft- 
 woods is rarely below 3 per cent. Hardwood ashes have 600 to 700 pounds lime per 
 ton of ashes. Mixture of coal ashes from factories would do no harm. 
 
THE USE OF WOOD FOE FUEL. 33 
 
 one factory which normally used 50 tons of soft coal a day used for 
 a month in mid-winter a minimum of 15 tons of coal and 50 cords 
 of mixed hardwood daily, from which the conclusion may be drawn 
 that for steam production 1 cord of green hardwood is equal to 
 seven-tenths of a ton of soft coal. Careful tests made in Georgia 
 showed that to keep a room at a comfortable temperature with an 
 open-hearth fireplace nearly 10 times as much wood must be con- 
 sumed as when a stove is used. This plainly indicates that it is very 
 uneconomical to depend on open fireplaces alone for heating houses. 
 
 WOOD FUEL FOR THE FUTURE. 
 
 GROWING TIMBER FOR FUEL. 
 
 There is probably a general impression that timber for firewood 
 can be grown rather rapidly, within a period of 5 to 10 years. This 
 will not hold true for general forest areas, especially hardwoods. 
 From 20 to 50 years and even longer are required to produce a full 
 stand. The sprout forests of southern New England will grow a 
 crop of wood in 10 or 15 years and perhaps less ; a full stand, how- 
 ever, requires more time. Planted catalpa on good soil will yield 
 fairly well in 8 or 10 years ; and eucalyptus or blue gum will produce 
 a heavy growth in five or six years. Willow and cottonwood on 
 suitable sites will yield firewood in from 10 to 15 years, but usually 
 a longer time is required for large yields even with these rapidly 
 growing species. Old field and white pine make rapid growth and 
 yield heavily in a comparatively short time. With hardwoods like 
 oak, hickory, maple, beech, birch, etc., not much can be expected in 
 less than from 30 to 50 years. 
 
 An average of 1 cord of fuel wood per acre per annum is a large 
 yield, taking the country as a whole. Hardwood forests will prob- 
 ably not average more than three- fourths of a cord growth per year 
 and many will not make more than one-fourth of a cord. With the 
 faster-growing species 2 cords per acre is a high average annual yield 
 even on favorable sites. With average natural stands of cottonwood, 
 cord wood can be obtained in about 16 years, with a total yield of 
 approximately 42J cords per acre, or an annual yield of 2.7 cords. 
 Under particularly favorable conditions of growth the time may be 
 shortened to 12 years, especially where thinning and cultivation are 
 possible. Since stands cut for cordwood can be most easily renewed 
 by coppicing, the second rotation should be much shorter than the 
 first because of the more rapid growth of the sprouts. Eucalyptus 
 in California is reported to yield as high as 7 cords per acre per an- 
 num on a comparatively short rotation. With the pines a yield of 
 over 4 cords per acre per annum has been reached. Only on the best 
 
34 BULLETIN ^153, U. S. DEPARTMENT OF AGRICULTURE. 
 
 sites and under suitable climatic conditions can such yields be ex- 
 pected even with these species. 
 
 FORESTRY. 
 
 It will not do for communities in wooded regions to depend on the 
 chance growth of wood for their future fuel supply. Already many 
 communities, especially in the Northeast, are finding it necessary 
 each year to go farther and farther back for their wood, or to cut 
 smaller trees each succeeding year, because the available supply of 
 standing wood is too small to allow the trees to grow to the proper 
 size before they are cut. 
 
 It is not too much to expect that the time will come and soon in 
 some regions when it will be necessary to provide definitely that cer- 
 tain areas be set aside to produce wood, and that they be so man- 
 aged as to produce the maximum amount of wood possible within 
 the shortest possible time. It is not desirable to devote good 
 agricultural land to growing an annual supply of fuel ; generally the 
 inferior land on farms will grow sufficient fuel to supply regularly 
 each year's needs. Farms with such land are numerous in the hilly 
 sections of the country, and are found almost everywhere except in 
 the prairie and plains regions and in limited areas in the river 
 bottoms. 
 
 Meanwhile, the least that should be done is to see that fire and other 
 destructive agents are kept out of growing woodland, and that when 
 cutting is done for firewood only that material is taken out whose 
 removal will not cause injury to the productive capacity of the 
 remaining stand. Advice on these matters will be freely given by 
 the various State forestry departments, or where they are not avail- 
 able, by the Forest Service of the United States Department of 
 Agriculture. 
 
 MUNICIPAL FORESTS. 
 
 Acute need for fuel in emergencies furnishes one of the strongest 
 arguments for maintaining municipal forests by cities or towns in 
 wooded districts where this is possible. These emergencies may be 
 expected periodically, and municipal forests serving as parks and 
 pleasure grounds or as protection to water supplies can come into 
 play as fuel reserves in time of stress when coal can not be obtained 
 in sufficient quantities for the needs of the communities. It is a point 
 well worth the thoughtful consideration of every community which 
 has woodland adjacent to it suitable for this purpose. Some towns 
 already own such tracts, and no doubt there will eventually be many 
 of these forests in the older settled sections of the country when it 
 is found how easily they are handled and how advantageous they are 
 in many respects. Instead of being sources of expense, well-managed 
 woodlands should quickly become sources of considerable revenue to 
 the communities owning them. 
 
THE USE OP WOOD FOR FUEL. 35 
 
 PROMOTING USE OF WOOD FOR FUEL. 
 
 PUBLICITY. 
 
 Where wood fuel has been little used or its use has been discon- 
 tinued for a long time, a great deal can be done toward developing 
 a demand for it by means of newspapers, motion pictures, illus- 
 trated talks, "cut-a-cord" clubs, "cutting bees," and posters. News- 
 papers are usually most active in advertising the work when fuel 
 conditions are acute. In the depth of winter when a shortage 
 is severe it is a matter of news and is "played up" a great deal, but 
 at other times it is difficult to use this medium of publicity. Motion 
 pictures may be used, with short, pithy sentences embodying facts 
 about Avood fuel. Lantern slides are being used to illustrate talks 
 on wood fuel given before clubs and various local organizations in- 
 terested in the subject. Posters carrying catchy slogans and con- 
 densed information have been devised in several States and have been 
 very effective. 
 
 "Cutting bees," so called, are organized efforts at getting out wood 
 by a crowd and are in the nature of a picnic. They are carried on 
 with great enthusiasm and rivalry, and well serve the purpose of 
 advertising the need of wood fuel and the means of getting it. 
 Other forms of organization can be used which suit the particular 
 locality and the spirit of the people, or existing organizations can 
 be turned in this direction. 
 
 "Cut-a-cord" club, as organized in New England and some other 
 sections during the winter of 1917-18, carry the "cutting bee" idea 
 still farther. Each member agrees to cut a definite amount of wood, 
 either one cord or several. Organization is made semipermanent, 
 so that the work is carried on more systematically than in the more 
 or less spontaneous "bees." 
 
 Many other ways can, of course, be devised to suit local conditions 
 and to arouse interest and action. The essential point is to arouse 
 the public from its inertia. 
 
 When the public realizes the necessity of returning to wood fuel 
 the advertising campaign is mainly finished. It should be succeeded 
 by a campaign of instruction in methods of producing wood fuel 
 and in organization for its production and distribution. With the 
 population concentrated at a distance from its fuel supply, as a 
 large part of it is to-day, and not accustomed to providing fuel in ad- 
 vance of need, individuals are not able to cope with an emergency 
 brought on by war, prolonged congestion of transportation, or inter- 
 ference with coal production. 
 
 A number of different organizations have been developed to meet 
 this situation, such as wood fuel committees, war fuel companies, 
 municipal wood yards, and "cut-a-cord" clubs. 
 
36 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 The wood fuel committees may be State, county, or community 
 organizations. In some States all three are used and all work more 
 or less closely with the Fuel Administration. Many municipalities 
 appoint such committees temporarily during the emergency winter 
 season to organize means of production and transportation of wood 
 as well as to equalize its distribution and price. All these com- 
 mittees should be made permanent, for much effective work can be 
 done by them during that part of the year when conditions are not 
 so acute. 
 
 As usually organized, a war fuel company is a stock company made 
 up of public-spirited citizens operating under a charter duly regis- 
 tered with the State. The object is to buy and sell wood and coal at 
 a low rate of return on the money invested, for the purpose of alle- 
 viating the undesirable conditions that are bound to follow wherever 
 sufficient fuel can not be had by families, business concerns, and 
 public institutions. The rate of profit is sometimes limited to not 
 more than 6 per cent and the proceeds are turned over to some 
 public charity. 
 
 WOOD FUEL LEGISLATION. 
 
 Doubtless in many cases State legislation would help to promote 
 the use of wood fuel. Price regulation, measuring, shipping, mar- 
 keting, and other features may be aided by specific laws adapted to 
 local conditions. 
 
 In Virginia an order has been issued by the Federal Fuel Admin- 
 istrator for the State prohibiting any person residing outside the 
 cities or incorporated towns from obtaining coal except by special 
 permit from the local administrator upon the execution of a state- 
 ment to the effect that wood is not available. This was done to bring 
 about the substitution of wood for coal to a very appreciable extent 
 without imposing serious hardship on those required to use wood. 
 Similar restrictions for most localities in the eastern United States 
 would seem desirable as a reasonable means of bringing about a 
 greater use of wood fuel by those who have wood around them or can 
 obtain it readily. This method is sufficiently elastic to accomplish 
 the object aimed at without working hardship on those who can not 
 reach wood. It should be especially valuable in the matter of coal 
 embargoes which may be suddenly found absolutely necessary in the 
 depth of winter in a fuel crisis. When an embargo must be laid, it 
 should be a flexible one and the heaviest restrictions placed on those 
 localities where wood is available and on those consumers who can 
 use wood fuel. In this way coal may be conserved and the evil effects 
 of a blanket embargo avoided. 
 
 MUNICIPAL WOOD YARDS. 
 
 In many places municipalities themselves organize wood yards to 
 purchase, manufacture, and distribute wood fuel, in order to sup- 
 
THE USE OF WOOD FOR FUEL. 37 
 
 plement the regular supply where no other agencies exist to take the 
 whole field. Wood handled by them is usually sold at cost. 
 
 In some States a grant of specific power is necessary before a 
 municipality can engage in the fuel business. In many cases in the 
 eastern United States last winter this fact was a serious obstacle 
 which prevented cities and towns from taking active relief measures 
 to keep the people warm and supply power to essential commercial 
 enterprises. In two States, Maine and Mississippi, public fuel yards 
 are specifically authorized by law. The Mississippi law, approved 
 April 21, 1918, authorizes municipal wood and coal yards. 1 The 
 essential features of this law are of especial interest in view of the 
 country-wide effort being made to provide against a fuel shortage 
 in the future. By this law 
 
 (a) The authorities of every municipality are authorized to establish and 
 operate wood and coal yards until one year after the close of the war, for the 
 purpose of supplying the inhabitants with fuel. 
 
 (&) A municipality which establishes and operates a wood yard or coal 
 yard has full power to create, fill, discontinue, or abolish all such offices or 
 employments in connection therewith as may be deemed necessary or proper; 
 to fix and pay salaries; to cut, purchase, transport, sell, and deliver wood or 
 coal necessary for providing the inhabitants with fuel; from time to time to 
 fix the selling prices and the terms of sale ; and to make and enforce such rules 
 and regulations as may be necessary for the carrying out of the act. 
 
 (c) The necessary funds are to be set aside out of the general municipal 
 fund, or borrowed at interest on the credit of the municipality. 
 
 (d) In order to borrow money for this purpose the municipality is required 
 to publish in local papers, for a period of ten days, a full statement of its inten- 
 tions, stating the sum needed and rate of interest to be paid. In case a protest 
 signed by at least 25 per cent of the qualified electors of the municipality is 
 filed before the expiration of the period of advertisement, the question must 
 then be submitted in an election requiring for passage the approval of a majority 
 of the qualified electors. 
 
 Similar action by other States is desirable. 
 
 WOOD FUEL RESERVES. 
 
 There is considerable difficulty in getting wood into suitable form 
 for fuel and transporting it to the market on short notice. It is 
 only a matter of good business foresight for those communities 
 which have the wood around them to see that some time during the 
 season a sufficient supply is cut and hauled to where it may be easily 
 available as a reserve for the winter season. The time to cut it is at 
 any slack time during the year, preferably in the spring, so that it 
 will have time to season thoroughly by the next winter. 
 
 Although Mississippi is the first State to respond with a law on the subject in the 
 present emergency, it is not actually the first to pass such legislation. As early as 1903 
 Maine passed a law allowing cities to establish public yards for sale of wood, coal, and 
 other fuel without financial profit. The Maine law has been sustained by the highest 
 court in the State and also by the United States Supreme Court. 
 
38 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 In this connection it is very desirable that reasonably close esti- 
 mates be made in advance of the amount of wood which will be 
 available to different communities from all sources. It would be a 
 comparatively simple undertaking to secure estimates of the amount 
 of fuel wood which is ready for use or which it is planned to cut for 
 the next winter. The figures should include (1) the number of cords 
 used in the previous year; (2) the number of cords cut, including 
 the amount left over from the previous winter; (3) the number of 
 cords to be cut for winter, say from September 1 to December 31. 
 Such figures would afford valuable bases not only for organizing 
 wood fuel work but also for allotting supplies of coal. 
 
 SUMMARY. 
 
 1. With enormous supplies of wood widely distributed over much 
 of the United States, especially the eastern half, there is no excuse 
 for suffering because of inability to get coal. 
 
 2. Wood is already widely used in rural districts; its use can and 
 should be greatly extended, at least during the present crisis, to save 
 coal and cars for more essential uses. 
 
 3. Wood can be substituted for coal with greatest public benefit 
 in places where rail-hauled coal can be replaced with wagon-hauled 
 wood. Long distance rail transportation of wood is not economical. 
 
 4. Domestic consumers in rural districts and small cities can most 
 easily substitute wood fuel for coal. Most types of stoves and 
 furnaces can be adapted to the use of wood. 
 
 5. Except in case of plants which use their own wood refuse, or 
 others in the close vicinity of such plants, wood fuel is less economi- 
 cal than coal for factories. When coal can not be had, however, 
 wood can be used with fairly satisfactory results, and is cheaper than 
 shutting down the plant. 
 
 6 The widespread use of wood for fuel, if only such wood as is best 
 fitted for this purpose be taken, will be of great benefit to our forests 
 as well as a source of revenue to their owners. 
 
 7. To promote the use of wood fuel, especially where it is not now 
 in general use, will require organized effort, preferably by com- 
 munity, municipal, or State organizations. Such effort should cover 
 the stimulation of demand for wood and stimulation of production 
 by private agencies, as well as direct organization of producing, 
 transporting, and marketing of wood fuel by the community. 
 
 8. Reserves of wood fuel should be established in all districts 
 where there is a possibility of fuel shortage. For the present these 
 reserves will probably consist largely of wood purchased from pro- 
 ducers ; it may eventually be advisable for communities to own their 
 own woodlands in order that they may more effectively regulate the 
 cutting and the price of fuel wood. 
 
THE USE OF WOOD FOR FUEL. 39 
 
 APPENDIX. 
 
 PUBLICATIONS ON WOOD FUEL. 
 
 Early in 1917 publications began to appear treating wood fuel 
 briefly with reference to local conditions. They were issued mostly 
 by States, and State foresters were chiefly instrumental in getting 
 them out. The first one appeared in June in the shape of a press 
 bulletin by K. W. Woodward of the New Hampshire Agricultural 
 College, Durham, N. H. This was followed by others until at least 
 20 have been published. Canada also published one early in 1918 
 modeled on those put out by the States. Future publications should 
 go into detail as to the quantity of wood fuel available in the State 
 and its distribution, as well as the amount of fuel wood cut and 
 -used by specific localities within the State. 
 
 RECENT PUBLICATIONS ON WOOD FUEL. 
 
 Emergency Fuel from the Farm Woodlot, by A. F. Hawes, Circular 79, Office 
 of the Secretary, U. S. Department of Agriculture. (Contributed by the 
 Forest Service, Washington, D. C., October, 1917.) 
 
 Firewood, by K. W. Woodward, Extension Circular 22, September, 1917, New 
 Hampshire Agricultural College, Durham, N. H. 
 
 The Fuel Situation, by K. W. Woodward, Extension Press Bulletin 77, June, 
 1917, Agricultural College, Durham, N. H. 
 
 Wood Fuel, by Paul D. Kneeland and F. W. Rane, Massachusetts State For- 
 ester's Office, 1917, Boston, Mass. 
 
 Wood Fuel, by R. D. Forbes, Assistant Forester, Department of Conservation 
 and Development of New Jersey. 1917, Trenton, N. J. 
 
 A press bulletin was issued October 13, 1917, by the State fuel administrator 
 at Greensboro, N. C., urging the cities and towns of the State to furnish wood 
 to consumers at cost as a war measure. 
 
 Wood as Emergency Fuel, by J. H. Foster and F. H. Millen, bulletin, department 
 of forestry, Agricultural and Mechanical College, 3d series, vol. 4, No. 2, 
 January 15, 1918, College Station, Tex. 
 
 Cordwood for Fuel, by J. H. Pratt and J. S. Holmes, Press Bulletin 160, North 
 Carolina Geological and Economic Survey, January 30, 1918, Chapel Hill, N. C. 
 
 Wood Fuel, by William G. Howard, assistant superintendent of State forests, 
 Bulletin 16, conservation commission of New York, 1918, Albany, N. Y. 
 
 Wood Fuel to Relieve the Coal Shortage in Eastern Canada, by Clyde Leavitt, 
 chief forester, commission of conservation, Ottawa, Canada, 1918. 
 
 Municipal Woodyards, by the Federal Fuel Administrator (Wood Fuel Depart- 
 ment for Georgia), Commerce, Ga., February, 1918. 
 
 Wood Fuel for Iowa, March, 1918, by Prof. G. B. McDonald, Iowa State College, 
 Ames, Iowa (in cooperation with Charles Webster, Federal fuel adminis- 
 trator for Iowa.) 
 
 Coal Conservation and Wood Fuel, March, 1918, State fuel administrator for 
 Minnesota. 
 
 Tamarack for Fuel, 1918, issued by the publicity department, Minnesota, com- 
 mission of public safety, St. Paul, Minn. 
 
 Wood Fuel and Democracy, 1918, State fuel administrator of Minnesota, St. 
 Paul, Minn. 
 
40 BULLETIN 753, U. S. DEPARTMENT OF AGRICULTURE. 
 
 Cordwood Producers, list furnished to Minnesota forest service for distribution, 
 
 March 12, 1918. 
 Firewood to Relieve the Coal Shortage, Forestry Leaflet No. 19, February 15, 
 
 1918, by F. W. Besley, State forester, Maryland State board of forestry, 
 
 Baltimore, Md. 
 
 Firewood and the Woodlot, Press Bulletin 1918, by Edmund Secrest, State for- 
 ester, Wooster, Ohio. 
 The Price of Fuel Wood, by William K. Prudden, State fuel administrator, 
 
 Lansing, Mich., March, 1918. 
 Wood and the Present Fuel Emergency, by John M. Briscoe, Maine Forestry 
 
 Association, February 6, 1918, Bangor, Me. 
 Municipal Woodyards, Circular 2, by T. A. Parker and James B. Berry, of the 
 
 wood fuel department of United States fuel administration for Georgia, 
 
 May, 1918. 
 
 GENERAL BIBLIOGRAPHY. 
 
 Betts, H. S. : Wood Fuel Tests. (U. S. Dept. of Agriculture, Forest Service, 
 Washington, D. C. Review of Forest Service Investigations, 193, Vol. 2, pp. 
 39-42.) 
 
 Bogue, E. E. : Some Determinations of Weight and Fuel Value of Green Wood. 
 (Forestry Quarterly, Washington, D. C., 1904, Vol. 2, pp. 275-276.) 
 
 Fisher, W. R. : Heating Power and Combustibility of Wood. ( In Schlich's 
 Manual of Forestry, London, Bradbury, Agnew & Co., ed. 2, 1908, Vol. 5, pp. 
 107-111.) 
 
 Fuel Value of Wood, The: (W. B. Campbell, forest products laboratories of 
 Canada, March 12, 1918. Canadian Forestry Journal, April, 1918, Vol. 
 XIV, No. 4) 
 
 Kollock, T. : Efficiency of Wood in Stoves and Open Fireplaces. (Forest, Fish, 
 and Game, Athens, Ga., April, 1911, Vol. 3, No. 6, pp. 95-97.) 
 
 Kreisinger, Henry and others. Combustion of Coal and Design of Furnaces. 
 144 p. il., pi., diagrams. Washington, D. C., 1917. (U. S. Department of the 
 Interior, Bureau of Mines. Bulletin 135. ) 
 
 Kreisinger, Henry : Five Ways of Saving Fuel in Heating Houses. 13 p. Wash- 
 ington, D. C., 1918. (U. S. Department of the Interior, Bureau of Mines. 
 Technical Paper 199.) 
 
 Pierson, Albert H. : Consumption of Firewood in the United States. 7 p. Wash- 
 ington, D. C., 1910. (U. S. Department of Agriculture, Forest Service. Cir- 
 cular 181.) 
 
 Record, S. J. : The Fuel Value of Wood. (Hardwood Record, Chicago, October 
 10, 1912, Vol. 34, No. 12, pp. 32-33.) 
 
 Schenck, C. A.: Heating Power of Wood (in his Forest Utilization, Biltmore, 
 N. C., Biltmore Forest School, 1904, pp. 64-65.) 
 
 Schenck, C. A.: Manufacture of Charcoal in Charcoal Kilns (Pits). (Logging 
 and Lumbering or Forest Utilization, pp. 166-168, 1912.) 
 
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