MASSACHUSETTS WOODLANDS. 13 



RESULTS OF THINNING. 



We said in the section on the " Theory of Thinning " that the 

 more light and air a tree receives the more rapidly it grows in 

 diameter; so that a thinning, by opening up the stand and allow- 

 ing the crowns of the remaining trees to enlarge, stimulates the 

 volume growth of the stand. There are fewer trees in the stand, 

 but larger and better ones. This may not be considered important 

 until we realize how much more valuable a tree of large diameter 

 is than a small one. For example, the average white pine, 10 

 inches in diameter breast high, and 60 feet in height, contains 

 95 feet of round-edge lumber; whereas a pine of the same height, 

 15 inches in diameter, contains 195 board feet of lumber; that is, 

 with a 50 per cent, gain in diameter there is an increase of 100 per 

 cent, in the product. This is not the whole story, because with the 

 increase in the size of the tree the boards are wider and have less 

 knots, yielding a higher price; so that the gain in money value 

 is even greater than the increase in volume. An average chestnut 

 tree 10 inches in diameter will produce 2 ties and .03 cords of fire- 

 wood. Supposing a railroad tie to be worth 50 cents, the tree may 

 be said to be worth about $1. A 15-inch chestnut will yield 5 ties 

 and .06 cords of wood, worth about $2.50, or an increase in money 

 value of 150 per cent. In the case of sprout oaks and other sprout 

 hardwoods, thinnings made at the right time may result in con- 

 verting what would otherwise be nothing but a cord wood lot into 

 one of saw-timber size. 



If, as a result of thinning, the trees become larger in a given 

 space of time, conversely they w r ill attain any suitable size in a 

 shorter space of time than without a thinning. The experiments 

 of European foresters have shown that the rotation of the timber 

 crop can be shortened by judicious thinnings from 10 to 20 per 

 cent. 



In the course of this work many unsightly and diseased trees 

 are removed, and this fact tends to make the woodland more at- 

 tractive to the eye. Where forest land is used for park purposes 

 as well as for timber production, a moderate thinning is highly 

 recommended. It should, however, be conducted under careful 

 supervision, as the tendency is often towards a " sand-papering " 

 treatment of the woods, to which many people who appreciate prim- 

 itiveness in nature object ; and they wrongfully believe this effect to 

 be a necessary result of forestry work. 



