1/2 THE LARCH. 



ill favour of thinning over not thinning to the amount 

 of £\J2 per acre. 



The above calculations show the proportional rather 

 than the true increase and value of the wood. In 

 consequence of the want of thinning till the lower 

 branches had withered and died, the trees lost the 

 means by wliich their growth was promoted, and 

 which under the best after-management could never 

 again be restored. 



On examining the concentric rings or layers of 

 wood of a number of trees in various parts of the 

 forest, wdiere they were cut and laid in heaps upon 

 the roadsides, it was quite observable where the proper 

 period of thinning had been exceeded. Most of the 

 trees planted at from five feet to six feet apart had 

 made annual layers of wood from one-sixth to one- 

 fourth of an inch thick till about twenty years old, 

 about which time the branches met each other, and 

 thus excluding light and air, speedily destroyed their 

 vitality. After this occurred the growths annually 

 decreased, and by the thirtieth growth, in many cases, 

 instead of making annual layers of one-sixth to one- 

 fourth of an inch in one year, one-fourth of an inch 

 was only made in four or five years. With these 

 facts before us, the urgency of thinning at the proper 

 time, in order to keep vital the lower branches, must 

 appear natural and reasonable to any one acquainted 

 with the laws of vegetation. The important function 

 of the lower branches to trees of any age (but espe- 

 cially young ones) is too little regarded. By the 



