THE WOOD CROP 



283 



builders, manufacturers, and other consumers. The policy of 

 the private timberland owners, until within recent years, has 

 been that of robbing the land of the standing timber without 

 regard to a future crop, and the practice of leaving the dead 

 timber and unused part of the trees on the land has resulted in 



m 



FIG. 135. Effect of thinning upon increased growth 



In a dense stand trees grow more rapidly in height than in diameter. The central part 



of this section of a lodgepole pine tree grew while the trees were crowded. The outer 



part grew after thinning took place. (Photograph from United States Forest Service) 



forest fires that have destroyed millions of acres of valuable 

 growing timber. Many of the regions that once supported 

 splendid forests are now barren wastes. 



Lumbering is usually a wasteful operation, and under care- 

 less methods far more material is destroyed than is marketed. 

 Under proper regulation, however, lumbering can be carried on 



