classes accounts for another 318 million board feet. 

 Most of these smaller trees should be left to produce 

 more and better material. This would mean that 

 the existing industries would have to depend more 

 on the large, high-quality timber, now growing 

 about 180 million board feet per year, in order to 

 maintain their cut. Even now this large high-quality 

 timber is being overcut by about 80 million board 

 feet per year (fig. 27) . 



On the other hand the growing stock of thrifty 

 young sawtimber trees is being built up. \Vithin 

 one or two decades the growth of these trees should 

 result in a sharp rise in the volume of high-quality 

 timber. Of course, good forest management would 

 speed up this process greatly. Nevertheless, barring 

 catastrophic losses or too rapid expansion of local 

 forest industries, some increase in the volume of 

 high-quality giowth is in prospect. 



ITEM 



NET GROWTH 



CCMMODITY DRAIN 



GROWTH-DRAIN COMPARISON 



200 400 600 



MILLION BOARD 



HARDWOODS 

 (Log Grades 182) 



HARDWOODS 

 (Log Grode 3) 



Figure 27— Net annual tim- 

 ber growth and commodity 

 drain, by log-qualitv class, 

 ]9-fS. 



22 



Forest Resource Report No. 7. U. S. Departinejit of Agriculture 



