204 



ON THINKIXG PLAKTATIONS 



example, a tree 12 feet high, should girth a little above the 

 swell of the root, 12 inches ; a tree 24 feet high, 24 inches, and 

 so on up to 30 or 35 feet in height, to a corresponding number 

 of inches in girth. When trees attain the above height, 

 thinning should be entirely discontinued, and frequently it 

 should not be prolonged after the trees are from 20 to 25 feet 

 in height, but allow the plantation to grow undisturbed (except 

 by cutting down dead or decaying trees) till it is ripe for cutting 

 down and clearinsj the Q-round. 



That there is a danger of old trees having too many, as well 

 as too few branches, I fully admit ; but there is no danger of 

 young trees having too many, and if the rule given should be 

 observed, there Avill be no superfluity of branches at any time, 

 for if the proportional girth is too great, it can soon (if their are 

 sufficient trees upon the ground) be reduced. 



Having found out by careful inspection, that a well pro- 

 portioned, and properly balanced tree measures as many feet in 

 height as it girths in inches, I was further anxious to know 

 what proportional weight the branches of such trees bore to the 

 stem on which they grew, and in order to ascertain this, I cut 

 down, in the process of thinning, some specimen trees of the 

 following species, and after carefully weighing them, I found the 

 following results : — 



The height and girth in the above table are not exactly 

 proportional, as it is very difficult in making a selection to find 

 them so, but the approximation is sufliciently near for the 

 purpose of showing the requirements of practical forestry 

 according to my definition. The form or outline of the tree up 

 to that period when thinning should be discontinued should be 

 conical or tapering, both in the stem and general form of the 

 tree. After thinning is discontinued the shape of the tree 

 alters, both in the stem and branches ; the latter wither and fall 

 off, till only the top is covered, and the former gradually 



