THE OUTLOOK FOR TIMBER SUPPLIES 131 



SAWTIMBER GROWTH, CUT, AND INVENTORY IN THE NORTH 



SOFTWOODS HARDWOODS TOTAL 



20 



Net Growth^ 



■Cut 



o " 



_Q 600 



c 

 o 



450 



.— 



Net Growth\ 



^' v-^: 



,*'"'"^( 



lut 



^,*<-Cut 



Inventory- 



300 



150 



Inventory 



.":>-. 





 1950 1960 1970 1980 



1990 2000 1950 1960 1970 

 Figure 58 



^.''' 



nventory---fc^ 





1980 



1990 2000 1950 I960 1970 1980 1990 2000 



tion for recreational use, and while such acquisi- 

 tion does not always preclude logging, some 

 restrictions on timber harvesting on these lands 

 are likely. Much of the land acquired or developed 

 for recreation, moreover, includes areas such as 

 river and lake borders which have relatively high 

 productivity for timber growing. Thus available 

 growth and inventories in the North could be 

 significantly less than the volumes projected. 



Stand Improvement of Particular 

 Importance in the North 



As indicated in the section on Forest Land and 

 Timber Resources, most forest lands in the North 

 are now fairly well covered with tree growth, 

 although much of it consists of relatively poor 

 growing stock trees or culls. Also, stand density 

 is steadily building up in the northern stands and 

 sizable further increases are projected, as shown 

 by the following tabulation of basal area per acre 

 (in square feet) : 



All Growing 



Year: live trees stock trees 



1962 77 68 



1970 85 75 



1980 95 84 



1990 102 90 



2000 106 93 



Average stand densities of the magnitude pro- 

 jected would involve serious overstocking in 

 many stands and a general decline in growth 

 rates. Thinning of stands and cull tree removal 

 would therefore have to be materially Stepped up 

 to maintain conditions favorable to improvement 

 in growth and quality. In many well-stocked 

 stands on productive sites such timber stand im- 

 provement work promises to yield early returns, 

 particularly where pulpwood markets can be 

 further expanded. In other cases where markets 

 for small and defective hardwoods are lacking, 

 such timber stand improvement work will require 

 investments for long periods before returns can 

 be expected. 



