64 THE PRINCIPLES OF HANDLING WOODLANDS 



times desirable to enlarge an opening beyond what is 

 necessar}' to remove a single mature tree. In such a 

 case one would aim to cut several trees in a group; 

 and in so doing it would often be necessary to cut trees 

 under the diameter limit. Usually, however, this can 

 be done without cutting medium trees of large promise. 



Protection from Windfall 



Very commonly a selection cutting would result in 

 windfall among the trees left standing unless this point 

 is regarded in the location of the trees to be cut. Some- 

 times it is necessary to cut whole groups clear, often as 

 large as an acre, because they cannot be thinned without 

 windfall. In niany cases a tree, or group of trees, above 

 the diameter limit inust be left standing to protect the 

 surrounding stand. 



Cutting Small Trees for Improvement 



The struggle for space in a selection forest is very 

 great. The old trees overtop and crowd those coming 

 up between and lielow them; the middle-aged trees 

 crowd and suppress the younger ones, while all the 

 competing trees are crowding one another. A poorly 

 developed tree of small promise may often injure 

 several trees of better form and species. The removal 

 of such poor trees greatly increases the total growth 

 of the stand. 



