Softwoods, mostly in old growth stands on the Pacific Coast, 

 account for over three-fifths of timber inventories. 



a major part in areas lacking access roads. National 

 Forests contained only 8 percent of all hardwood 

 growing stock. 



Farmer and other private ownerships contained the 

 major part of the Nation's inventory of hardwoods — 

 about 70 percent — and a substantial part of all soft- 

 wood inventories — about 27 percent. Nearly all of 

 this timber is readily accessible from existing road 

 systems and is favorably located in respect to the 

 major timber-consuming centers. 



Forest industries held 16 percent of all softwood 

 inventories in 1977, and a somewhat smaller portion 

 of hardwoods. Nearly all of this timber is accessible, 

 to primary timber processing plants. 



Public agencies other than the Forest Service held 

 roughly 11 percent of all timber inventories in 1977. 

 Nearly all of these inventories are accessible and are 

 important sources of timber for processing industries 

 in the Pacific Northwest and the Lake States. 



Timber Mortality 



Annual mortality losses from natural causes — fire, 

 insects, disease, storms, and other destructive agents 

 — were estimated at about 4 billion cubic feet of 

 growing stock in 1976 (table 6.17). Mortality of saw- 



timber amounted to an estimated 12 billion board 

 feet (2.2 billion cubic feet). About 2.3 billion cubic 

 feet of growing stock mortality and nearly three- 

 quarters of sawtimber mortality was in softwood 

 species. 



There has been some decline in mortality in the last 

 couple of decades. This has been entirely in softwood 

 mortality and reflects the reduction in the area of 

 old-growth stands, which have high natural mortal- 

 ity, in the Rocky Mountains and Pacific Coast. Hard- 

 wood mortality has shown some increases, a result of 

 the build-up in inventories and the associated in- 

 crease in stand crowding. 



Most softwood mortality in 1976 was in the west- 

 ern United States, chiefly in the Pacific Coast section. 

 This distribution is related to the concentration of 

 timber volumes in this area and the high proportion 

 of overmature timber characteristic of old-growth 

 stands. Much of the sawtimber loss was in trees con- 

 taining large proportions of high-quality material. 



Timber mortality on the National Forests amounted 

 to 1 billion cubic feet of growing stock, including 4.4 

 billion board feet of sawtimber. The bulk of this 

 material was softwood, in fact, nearly half of the 

 softwood sawtimber mortality occurred on the Na- 

 tional Forests. The primary cause of death has been 

 insect infestation and drought, mostly on the over- 

 mature trees in the old-growth stands. 



While representing a significant volume — equiva- 

 lent to slightly more than a third of the 1976 softwood 

 removals from Forest Service lands — nearly all of 

 the mortality on the National Forests occurs in areas 

 which are unroaded and inaccessible for trucks and 

 tractors. Moreover, much of the mortality is scattered 

 over large acreages which precludes prompt detection 

 and treatment. With the existing technology, the 

 present location of processing plants, and current 

 product prices, salvage of such mortality is not eco- 

 nomically feasible in most forest stands including 

 those in roaded areas. 



Net Annual Timber Growth 



Net annual growth (i.e., total annual gross growth 

 less mortality) on growing stock was 22 billion cubic 

 feet in 1976 (table 6.18). There were substantial 

 volumes of growth in all regions and sections of the 

 country. More than half of the growth was in the 

 forest stands in the South. This is to be expected since 

 most stands in that section are relatively young and 

 vigorous. In the West, mortality in the old-growth 

 stands offsets much of the total annual growth. As a 

 result, net annual growth in the western sections was 

 5.2 billion cubic feet or less than 25 percent of the 

 national total. 



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