146 The Farm Woodlot 



Later thinnings, following possibly ten or fifteen years 

 later, usually pay for themselves and in some cases are 

 profitable even when the woodlot owner can use the wood on 

 his own farm. Thinnings made in a stand thirty or forty 

 years old of the average species of our forest trees are 

 made with a different object in view from that of the 

 early thinnings. At this time most of the trees will have 

 attained their principal height growth, and if allowed to 

 remain unthinned will become tall and lanky. The 

 chopper again must look to the crowns of the trees rather 

 than to the number standing on the ground so as to give 

 each tree an equal and sufficient amount of crown space. 

 This admitting of more light enables each tree to develop 

 more leaf surface, consequently to grow very rapidly in 

 diameter, thus laying on large quantities of wood. It is 

 rare that a farmer with a small woodlot will care to grow 

 trees for a particular use, but he can always use to best 

 advantage tall, well-developed trees of various sizes. It 

 seems best then to encourage height growth first by a 

 close stand and then by thinning at the proper time, to 

 provide for the rapid increase in diameter. This has in 

 every case a tendency to produce well-developed trees. 



KIND OF THINNINGS 



In a general way thinnings may be considered as of two 

 kinds, first, improvement thinnings, and second, reproduc- 

 tion thinnings. Each of these may be given a paragraph. 



Improvement thinnings 



Improvement thinnings have as their purpose merely 

 the improvement of the present stand. This may consist 



