56 IMPORTANT TIMBER TREES 



size, the quality and character of the lumber cut from it 

 increase in value. This is generally known by manufac- 

 turers, dealers, and consumers. Illustrating this fact, Mr. 

 Edward A. Brainiff, in Forest Service Bulletin No. 73, 

 page 20, 1906, says : " The quality of lumber in a tree 

 increases rapidly as the tree increases in size. An eighteen 

 inch tree would hardly be profitable to cut with Yellow 

 Poplar averaging $23 per thousand. At nineteen inches 

 it would yield an average profit of eighty-two cents per 

 thousand; twenty inches, $1.32; at twenty-one inches, 

 $1.99; at twenty-two inches, $2.67." Without doubt part 

 of this increase in value comes from the increased propor- 

 tion of heartwood to sapwood, and part from some chem- 

 ical change taking place in the former. This would be true 

 of all the pines and many of the hardwoods. The change 

 from sapwood to heartwood is not so beneficial in some of 

 the hardwoods, especially Sugar Maple and the Hickories, 

 as with Walnuts, Oaks, Cherry Gums, and some others. 

 As a rule, however, the value of wood increases with the age 

 of the tree. 



(4) To determine the period when compound interest on 

 the investment overtakes the accretion in a planted forest 

 is a more difficult matter. European experience shows that 

 from the time of planting up to the age of sixty or seventy 

 years for Pine, Spruce, Larch, and some other conifers, and 

 sixty or seventy for broadleaf trees, the accretion is greater 

 in value than the accumulated cost of planting, care, and 

 compound interest on the investment, but that after the 

 periods named the interest account increases more rapidly 

 than the value of the annual growth. But notwithstanding 

 this fact the cost of labor and the price of forest products 

 in the markets must largely if not entirely prevail in 

 determining when to harvest; and these cannot be known 

 until met. There are many uses for wood when old age on 

 the part of the trees is not so essential as it is for saw tim- 

 ber, and in such cases harvesting can be undertaken much 

 earlier. Still, it must be remembered that to cut a tree for 



