A SUMMARY OF THE TIMBER RESOURCE REVIEW 



growing tree is no longer a factor to be considered 

 with respect to timber supplies, and that national 

 needs will be adequately met merely by growing 

 sufficient cellulose irrespective of size, species, 

 condition, or growth rate. Others contend that 

 quality of raw material will be as significant in 

 the future as in the past and appear to overlook 

 technological gains. 



Despite the progress in technology, wood of 

 good quality is needed to produce many of the 

 kinds of wood and wood-fiber products that are in 

 demand. Good laminated arches, ship timbers, 

 and other structural members, for example, are 

 not fabricated from wood of nondescript quality. 

 It is incorrect to assume, as some do, that wood 

 quality is unimportant for pulp, paper, or wood- 

 fiber products. Fiber yield, length, and strength, 

 felting properties, and uniformity of raw material 

 are important wood characteristics for such uses. 



Despite technological progress, it is likely that 

 quality of standing timber will become more 

 instead of less of a problem during the next 

 several decades. In view of this, and although 

 quality is not as essential as formerly, the safe 

 policy appears to be to continue to grow substan- 

 tial amounts of high-quality timber. With proper 

 cultural measures, quality timber of required 

 species, size, and grade can be grown in less time 

 than was needed to produce the old-growth forests. 



Protection Against Destructive 

 Agents 



One of the greatest deterrents to present and 

 future productivity of forest land is the damage 

 caused by fire, insects, disease, weather, animals, 

 and other destructive agents. These affect growth 

 in many ways. They kill trees. They weaken 

 tree vitality and slow up growth. Trees may be 

 deformed or stunted. Seed may be eaten and 

 seedlings eaten, grubbed out, trampled, or broken. 

 Everyone is familiar with the damage that may 

 be wrought by ice, snow, flooding, blowdown, and 

 drought. Understocking may result from these 

 agents, as may site deterioration, poorer timber 

 quality, and encroachment of inferior species. 



The estimated total mortality in 1952 from all 

 destructive agents was 12.7 " billion board-feet, 

 or an amount equivalent to one-fourth of net 

 sawtimber growth (fig. 28). About 3.1 billion 

 board-feet were salvaged. In addition to this 

 annual mortality loss, there are further losses from 

 growth that greatly exceed mortality. These 

 total losses referred to as "growth impact" were 

 estimated in 1952 at 43.8 billion board-feet, a 

 figure approaching the net sawtimber growth. 

 If such losses could be materially reduced, the 

 added timber available for use would go a long 



'2 See footnote 2, table 29, p. 48; and footnote 1, table 

 39, p. 64. 



61 



ANNUAL 



GROWTH 



IMPACT OF 



SAWTIMBER 



IN BILLIONS OF BOARD-FEET 



MORTALITY OF 



SAWTIMBER IN 1952 



(3.1 SALVAGED) 



'2.7 



y.~'«|-?i 



ANNUAL 



GROWTH 



LOSS 



3 J. J 



SAWTIMBER 

 GROWTH 

 IN 1952 



includes Coastal Alaska 



Figure 28 



way toward meeting the country's increasing 

 needs. Growth-cut relationships in both saw- 

 timber and growing stock would become more 

 favorable in many localities, and projected demand 

 estimates would appear much easier to attain. 



Growth Impact — A Concept for Esti- 

 mating Total Losses 



In attributing losses to various destructive 

 agents, an effort has been made to reflect the full 

 impact of these losses on growth. It has long been 

 recognized that mortality loss occasioned by a 

 destructive agent may be insignificant in terms 

 of measured volume, yet the annual loss of sound 

 standing timber, through reduced growth, may be 

 very large over a period of years. Thus, total 

 or partial destruction of a seedling or sapling 

 stand results in no immediate mortality measura- 

 ble in terms of board-feet or cubic feet, but in later 



