(From the Forest- Service, United States Department of AgricuIL- 



UNITLD STATES DEPARTMENT OF AGRICULTURE 

 FOREST SERVICE 17C-F 



THE FUEL VALUE OF W007; 



The fuel value of two pounds of wood is roughly equiv- 

 alent to that of one pound of coal. This is given as tho re- 

 sult of certain calculations new being made in the Forest 

 Service laboratory which show also about how many cords of 

 certain kinds <.-f wood are required to obtain an amount of 

 heat equal to that in a ton of coal. Certain kinds of wood , 

 such as hickory, oak, be?ch, birch, hard maple, ash, elm, 

 locust, longleaf pine, and cherry, have fairly high heat 

 values and only one cord of seasoned wood of these species 

 is required to equal one ton of good coal. It takes a cord 

 :.i',d a half of shortleaf pine, hemlock, rod gum. Douglas fir, 

 .yoamore, and soft maple to equal a ton of coal, a/id two cord'J 

 of CGoar, redwood, poplar, catalpa, Norway pine f cypress, 

 "uasswood, spruce, and white pine. 



Equal weights of dry, non-resinous woods, however, are 

 said to have practically the same heat value regardless of. 

 species', and as a consequence it can be stated as a general 

 l .reposition that the heavier the wood the more hsat to the 

 cord. r 'e ight for weight, however, there is very little dif- 

 ference between various species; the average "neat for all 



L ' ' 



that have been calculated is 4,^00 calorics, or heao units, 

 i^er kilogram. A kilogram of resjn w?.ll develop 9.400 heat 

 units, rr about twice the average for wood. As a consequ^r.- 

 resinous woods have greater heat value per pound than no:?.-- 

 resinous woods, and this increased value , var ie-3 , of course, 



