164 



STUDIES OF TREES 



branches. This process is known as " heading back." It 

 is a method, however, which should not be resorted to 

 except in trees that are very old and failing, and even 

 there only with certain species, like the silver maple, syca- 



FIQ. 114. A Limb Improperly Cut. Note how the stub is decaying 

 and the resulting cavity is becoming diseased. 



more, linden and elm. Trees like the sugar maple will not 

 stand this treatment at all. The willow is a tree that 

 will stand the process very readily and the Carolina poplar 

 must be cut back every few years, in order to keep its crown 

 from becoming too tall, scraggy and unsafe. 



Covering wounds: The importance of immediately 



