NATURAL REGENERATION. 135 



The several systems comply with these conditions in a 

 varying degree. In order to bring out the general 

 characteristics of the methods, it is desirable to com- 

 mence with a description of the compartment system. 



1. The Compartment System of Natural Regeneration 

 under Shelter- Woods. 



The regeneration occurs approximately at the same 

 time and uniformly over a whole wood, which, for con- 

 venience sake, is here called |a compartment. The area 

 treated at one time and in a uniform way is called the 

 regeneration area. The new crop should, if possible, be 

 created by one seed year over the whole regeneration 

 area ; this, however, succeeds only in exceptional cases, 

 so that, as a rule, two or even more seed years are 

 required to complete the regeneration. As a consequence 

 the regeneration process may extend over a term of 

 5, 10, 15, and sometimes even more years, resulting in 

 a new crop which is only approximately even-aged. 



The cuttings are made from time to time as required, 

 and so that the old or shelter-wood gradually makes 

 way for, and is replaced by, the new crop, the process 

 being as uniform as practicable over the whole regenera- 

 tion area. These successive cuttings are, for convenience 

 sake, generally arranged into three groups, each of which 

 represents a distinct stage, namely, 



(.) The preparatory stage. 

 (b.) The seeding stage. 

 (c.) The final stage. 



Theoretically speaking, the preparatory and final 



