12 Characteristics, Structure, Life of Trees 



violent death and diminution in numbers, more or less pro- 

 portionate to food supply and new births, in order to keep 

 an equilibrium, so in the forest a constant diminution of 

 individuals takes place as the stand grows up and the indi- 

 vidual trees expand, competing for the limited air space and 

 root space. 



Fig. 4a. — Theoretical (B) and actual (A) development of buds. (From 

 Department of Agriculture, Forestry for Farmers, after Miiller.) 



So also in the individual tree there exists a competition 

 for light and water between the many buds, twigs, and 

 branches, and sooner or later some must succumb as their 

 number increases and the supplies become relatively less. 



As a result, in the full grown tree rarely more than eight 

 or ten generations of branches can be counted, — the sur- 

 vivals of this competition; the rest having been killed out, 

 and being annually killed out, by the necessity of household 



