THINNING 85 



period while height-growth is vigorous. A stuffy 

 feeling of the air in a plantation, lanky stems, 

 a bark which instead of a dark brown, with 

 streaks of rich brown, is pale and close, and 

 roots appearing out of the ground are signs that 

 the time for a thinning has come. In their 

 absence there is no necessity to thin merely 

 because the boughs of the trees interlace. Even 

 when a thinning is desirable, it may, if financial 

 reasons make that convenient, be postponed for 

 one or two years without serious risk, by knock- 

 ing off the dead lower branches of the larch so 

 that there may be an additional access of air 

 to the interior of the plantation. 



No definite rules can be laid down about the 

 distances at which the trees should stand apart 

 after a thinning. The circumstances of each 

 plantation are different. In the same planta- 

 tion there may be groups of poor trees close to 

 each other, and also groups of good trees. No 

 prudent owner would remove both good and 

 bad trees in the same proportions; he would 

 preserve as many as possible of the good trees 

 and remove as many as possible of the bad. 



The general principle in thinning a plantation 

 is to remove from it exactly so many trees and 

 in such situations that those which are left 



