Growth and Drain 



Gross annual growth of merchantable sawtimber trees (based on the 1934- 

 44 period) before allowances for cutting and mortality averaged 45 MM 

 board feet (Scribner). Mortality (fire, insects, disease, etc.) aver- 

 aged 15 MM feet, leaving a net annual growth before deducting for com- 

 modity uses of 30 MM feet annually from 1940-44. The net effect of all 

 drain and growth during the past 5 years has resulted in a reduction of 

 the forest resource at the rate of 42 MM feet annually in contrast with 

 an average annual reduction of 37 MM feet from 1929-33. Gross board- 

 foot growth has been decreasing since 1933 because of reduction in the 

 sawtimber growing stock. Mortality, however, has been decreasing at 

 about the same rate because of lowered fire losses and the reduction of 

 the area occupied by decadent stands. Net annual growth before allow- 

 ance for commodity drain has remained relatively constant at from 30 to 

 35 MM feet. 



GROSS ANNUAL GROWTH 



£4,000,000 

 Board Feet 



1929-33 



4-5,000, 000 

 Board Feet 



1940-45 



ANNUAL DRAIN 



Commodity 

 70,000,000 Board Feet 



Mortality 

 21 MM 

 Bd. Ft 



1929-33 



Commodity 

 72, 000, 000 Board Feet 



1940-45 



Mor 



tality 

 J5MM 

 3d. Ft. 



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