478 



TIMBER RESOURCES FOR AMERICA'S FUTURE 



There is also a likelihood that new uses for 

 wood wUl appear which were not anticipated in 

 the demand estimates. The rapidit}^ of new 

 developments in wood utilization during recent 

 years lends support to an extra allowance for 

 possible increased timber cutting resulting from 

 such developments. A third source of additional 

 withdrawals from inventory is the pressure of a 

 rapidh' growing population to convert commer- 

 cial forest land to other uses. Additional land 

 will be needed for residential development, high- 

 ways, reservoirs, recreation, and watersheds. 



Because inventory is the source of growth, it 

 must be maintained at a level large enough to 

 produce a net growth equivalent to timber cut. 

 If needed growth is no larger than timber cut, 

 the withdrawals from inventory additional to 

 timber cut are not replaced by growth and reduce 

 inventory. These reductions accumulate with 

 time, and the resulting depleted inventory be- 

 comes inadequate to produce the growth neces- 

 sary to sustain needed timber cut. So if inventory- 

 is to remain large enough to sustain timber cut, 

 the volume added by growth must be large enough 

 to replace not only timber cut but also with- 

 drawals from inventory expected from catas- 

 trophes, unanticipated new uses of wood, and 

 conversion of commercial forest land to other 

 uses. Margins representing given percentages of 

 timber cut under lower projected demands were 

 adopted to account for these three sources of 

 inventory reduction, and the calculated volume 

 was added to both lower and medium projections 

 of timber cut. 



Although net losses from catastrophes may 

 decrease somewhat in the future, new uses for 

 wood and conversion of commercial forest land 

 to other uses are more likely to increase with 

 length of the projection period. Because of this, 

 the margins adopted gradually increase from 1953 

 through 2000 (table 282). Average margins for 

 the entire projection period were 6.5 percent of 

 the cut of sawtimber needed to supply the lower 

 estimate of projected demand and 5.2 percent of 

 the cut needed to supply the medium projected 

 demand. Margins added to the timber cut of 

 growing stock are approximately the same as 

 those shown for sawtimber in table 282. 



Timber Removal Rises Sharply 



The timber removal necessary to supply medium 

 level demands for sawtimber in 1975 and 2000 will 

 be 68.2 and 105.4 bUlion board-feet, respectively 

 (table 283). For lower level demands, sawtimber 

 renioval in 1975 and 2000 will be 58.8 and 79.3 

 billion board-feet, respectively. The estimates 

 of timber removal for each demand level are large 

 increases over the timber cut of 48.8 billion 

 board-feet in 1952 (table 284). 



Western species would produce a substantial 



share of total timber removal under both levels of 

 demand. For the first half of the projection 

 period, this share would be about the same pro- 

 portion of total removal as in 1952, or 46 percent 

 (table 284). However, for the last half of the 

 period, this proportion declines slightly. For 

 example, in 1975 at the medium level of saw- 

 timber demand, removal of western species esti- 

 mated at 31.7 billion board-feet is still 46 percent 

 of a total removal of 68.2 billion board-feet. In 

 2000, removal of western species will be 42.8 

 billion board-feet — 41 percent of the 105.4 billion 

 foot total. 



Table 282. — Margins for contingencies, by levels 

 of demand and periods 



Period or vear 



Margins of sawtimber 

 cut added to cut 

 under — 





Lower 

 projected 

 demand 



Medium 

 projected 

 demand 



1953 



Percent 

 

 1 

 4 

 5 

 7 

 12 

 15 



Percent 







1953-64 



1965-74 



1975 



1 

 3 



4 



1975-84 



1985-99 



2000 



6 



9 



11 







Average 



6. 5 



5. 2 



For eastern hardwoods and eastern softwoods, 

 removal of sawtimber in 1975 at the medium 

 demand level would be nearly equal at about 18 

 billion board-feet for each species group. At the 

 lower demand level, removal of these two species 

 groups would also be the same in 1975 at 15.7 

 billion board-feet for each species group. How- 

 ever, by 2000 removal of eastern softwoods at 33.2 

 billion board-feet for the medium demand level 

 and 24.9 billion board-feet for the lower level 

 would supply higher proportions of total national 

 timber removal than in 1975. Eastern hardwoods 

 would also supply a slightly higher proportion of 

 total removal than in 1975. 



These increases for the two eastern species 

 groups offset the decrease for western species and 

 indicate that during the period 1975 to 2000 the 

 East would bear a slightly larger share of timber 

 removal of sawtimber than during the first half 

 of the projection period. Thus, up to the year 

 2000, western species with heavy volumes of old- 

 growth timber would support more than 40 per- 

 cent of the total national removal of sawtimber. 

 The west would be supplied about equally by 

 eastern hardwoods and eastern softwoods until 

 1975; after that, eastern softwoods primarily would 



