21 



If the thicket to be turned into a sugar grove contains older and 

 larger trees than have been considered, a regular course of thinning 

 should be instituted. The main points to keep in mind in this case 

 are as follows : 



(1) Choose the thrifty trees which show a tendency to good, sym- 

 metrical crown development, and set their crowns free on all sides to 

 a distance of about 12 feet. See that the selected trees are sound and 

 free from forks which may develop badly. 



(2) Remove all long, spindling trees which are likely to bend over. 



(3) For ground cover, leave all specimens which do not threaten the 

 crowns of the chosen trees and which are capable of casting a small 

 amount of shade. 



FIG. 3. Method of improving a thicket of maple saplings. 



(4) Remove all species but maple, except when they are very much 

 suppressed. Low, broad-crowned trees of any kind will help to shade 

 the ground. 



(5) Do not disturb the borders of a dense thicket. Sun and wind 

 must be excluded from a stand which has been suddenly opened up 

 within, and which is unaccustomed to the new conditions. 



To make this system of treatment clearer, a concrete case will be 

 described. In the autumn of 1903 a stand of young maples in Ver- 

 mont was thinned by a member of the Forest Service. The stand 

 is situated at an altitude of about 1,200 feet, with a southeastern 

 exposure. It came up in an abandoned meadow, which was seeded 

 from a few old trees along a bordering wall. The dominant trees 

 are from 30 to 40 feet in height and from 15 to 25 years old, with an 

 average diameter for the stand, suppressed trees included, of 2 inches, 



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