Practical Sylviculture 151 



more space in a stand for such a tree by thinning, its diam- 

 eter may be increased to 15 inches with practically no 

 increase in height, thus increasing the volume from 95 to 

 195 board feet. This is a gain in diameter of 100 per cent, 

 aside from the better quality of wood produced. An 

 averaged developed chestnut tree 10 inches in diameter 

 will produce two railroad ties and about one-third cord of 

 wood. The same tree with a five-inch increase in diam- 

 eter will yield five ties and one-half cord of wood. This 

 means an increase in tie value alone of 150 per cent. This 

 may also be applied, but with slightly less increase, to oak. 

 Hardwood sprout growths in the woodlot by judicious 

 thinning may be converted from a cord wood to a log 

 proposition. This increase in value is the result of rapid 

 growth of individual trees through careful thinning, often 

 bringing them to commercial maturity ten or twenty 

 years earlier than if left unthinned. The quality of the 

 timber is largely increased through clear, straight, tall 

 and even-grained trees. In addition, the woodlot is kept 

 clear of diseased and insect infested trees, danger from 

 fire is reduced to a minimum, all parts are made more 

 readily accessible and the general appearance and aesthetic 

 value are greatly improved. 



In a woodlot of white pine in New England in which 

 thinning operations were carried on, there were trees 

 ranging in diameter from five to twenty-two inches, in 

 height from sixty to seventy feet and spaced approximately 

 on an average twelve by twelve feet, or about three hun- 

 dred trees to the acre. Thinnings were made as shown 

 in the following table : — 



