Show FUEL VALUE OF WOOD the fuel value of two pounds of wood is roughly equivalent to that of one pound of coal this is given as the result of certain calculations now nosy being made in the forest service laboratory which show also about how many cords of certain kinds of wood are arc required to obtain an amount of heat equal to that in a ton of coal certain kinds of wood such as hickory oak beech birch hard maple ash elm locust longleaf pine and cherry have fairly high heat values and only one cord of seasoned season edwood wood of these species is required to equal one to of good coal it takes a cord and a half of shortleaf short leaf pine hemlock red gum douglas fir sycamore and soft maple to equal a ton of coal and two cords of cedar redwood red poplar catalpa norway pine cypress basswood spruce and white pine equal weights weight 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 proposition that the heavier the wood the more heat to the cord weight for weight there is very little difference between various species the average heat for all that have been calculated is calories or heat units per kilogram A kilogram of resin will develop heat units or about twice the average for wood As a consequence resinous woods have a greater heat value per pound than non resin ous woods and this increased value varies of course with the resin content the available heat value of a cord of wood depends on many different factors it has a relation not only to the amo resin it contains but the amount of moisture present furthermore cords vary as to the amount of solid wood they contain even when they are of the standard dimension and occupy cubic feet of space A certain proportion of this space is made up of air spaces between the sticks and this air space may i be considerable in a cord made of twisted crooked and knotty sticks out of the cubic feet a fair average of solid wood is about 80 90 cubic feet |