62 



A PRIMER OF FORESTRY. 



ratusin the leaves should be able to furnish, a large sup- 

 ply of digested food. Consequently the struggle for 

 space is fiercely renewed, only now the trees no longer 

 attempt to overtop one another, having lost the power, 

 but to crowd one another away at the sides. (See fig. GO.) 

 The whole forest might suffer severely at this point from 

 a deadlock such as sometimes happens in early youth 



were it not for the fact that the trees, as they grow 

 older, become more and more sensitive to any shade. 

 Many species which stand crowding fairly well in youth 

 can not thrive in age unless their crowns are completely 

 free on every side. Each of the victors in this last 

 phase of the struggle is the survivor of hundreds (or 

 sometimes even of thousands) of seedlings. Among 



