550 



RELATION TO ENVIRONMENT. 



not shade-endurers or do not develop coppice. Broad-leaved 

 trees are limited, however, in their competition with conifers on 



Fig. 502. 



Coppice from redwood showing sprouts 6 to 8 years old. 

 Bureau of Forestry.) 



(From Bull. 38, 



thin sandy soil, and in cold regions, because many species of the 

 latter can grow with a lower sum total of heat. 



1035. Artificial regeneration of forests. This is accomplished 

 by the aid of man, and is one of the lines of forestry work which 

 we call silviculture. This work may vary in intensity all the 

 way from leaving a few seed-trees in the forest here and there, 

 when cutting out the merchantable timber for self-seeding, to 

 the complete reforestation of completely deforested areas. The 

 extent to which artificial regeneration of forests can be success- 

 fully undertaken from a business standpoint will depend upon 

 the condition of the forest, the price of lumber, expense of oper- 



