8 FORESTRY IN NEW ENGLAND 



forestry, based on this knowledge, tries to develop in every 

 locality the type which is best fitted to exist there. 



The term "stand" is the unit of description applied to any 

 definite portion of a forest having a definite distinguishing char- 

 acteristic. Thus in a certain type we may have a stand of 

 young growth; a stand of diseased and damaged trees; a stand 

 of exceptionally tall specimens, etc. These stands may be ex- 

 tensive, covering many acres or they may be confined each to a 

 small part of an acre. 



Fig. I. — Two stands uf white pine of dififerent age classes. The one at the right is 40 years, 

 that on the left 70 years of age. 



Forest Types. 



In every forest the ceaseless struggle going on gradually 

 brings about many changes unseen by the casual observer. 

 In the small openings of the forest, caused by windfall, snow 

 breakage, or other causes, seeds of trees germinate and begin 

 to grow. The kind of trees that come up here depends, as 

 has already been shown, on many factors — the kinds of seed 

 trees near, the covering of the soil and moisture content, the 

 light available, etc. On the burned-over and freely-exposed 



