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Large-scale use of the timber resource of southeast Alaska began in 1953 after long efforts to establish a timber industry. Development and present status of the industry and present management of the timber resource are summarized, stressing the biological basis for timber management activities in southeast Alaska today. Ecological and silvicultural considerations related to timber harvest, reforestation, and stand development are discussed. Published and unpublished information are brought together. Current management practices are discussed as a basis for a better understanding of how this information can be helpful in managing the timber resource and to point out where research is needed.
Properties and grade yield are estimated for structural lumber produced from No. 3, No. 4, and low-end No. 2 grade western hemlock logs of the type previously used primarily for the production of pulp chips. Estimates are given for production in the Structural Framing, Machine Stress Rating, and Laminating Stock grading systems. The information shows that significant amounts of higher grade structural lumber can be produced from these lower grade logs.
The disease problems of old growth are largely being taken care of by cutting. This same cutting is rapidly converting large areas of old growth to reproduction and young growth. It is in these areas of young growth that our disease problems will most probably arise. With a few exceptions the reproduction and young-growth stands appear quite healthy at this time with the diseases that are present just doing a bit of natural thinning. These new stands should be closely studied. Damage appearing in young stands may be due toor may be corrected bycertain silvicultural practices such as thinning, or perhaps completely prevented by a modification of the methods used in removing the previous stand.
This publication presents highlights of a recent southeast Alaska inventory and analysis conducted by the Pacific Northwest Research Station Forest Inventory and Analysis Program (USDA Forest Service). Southeast Alaska has about 22.9 million acres, of which two-thirds are vegetated. Almost 11 million acres are forest land and about 4 million acres have nonforest vegetation (herbs and shrubs). Species diversity is greatest in western hemlockAlaska cedar closed-canopy forests, in mixed-conifer open and woodland forests, and in open tall alder-willow shrub type. Of the forest land, 4.1 million acres are classified as timberland (unreserved productive forest land). About 4.4 million acres of forest land are reserved from harvest; the majority of this reserved land (85 percent) is on the Tongass National Forest (USDA Forest Service). The volume of timber on timberland was estimated at 21,040 million cubic feet; the majority of volume88 percentis on the Tongass National Forest. Seventy-four percent of timberland acres and 84 percent of the growing-stock volume is in sawtimber stands older than 150 years, with western hemlock or western hemlockSitka spruce mix predominating. Most timberland in southeast Alaska is of relatively low productivity, producing less than 85 cubic feet per acre per year. For most timberland acres, average annual growth exceeds average annual mortality and harvest.
Southeast Alaska's remaining virgin forests have few insect pests. The black-headed budworm and the hemlock sawfly, both western hemlock defoliators, are the most important species. They kill some trees, kill tops in others, and cause growth loss, but stands survive their attacks. Extensive conversion of virgin stands to second growth may result in an increase in pest problems as it has in similar areas such as coastal British Columbia. ‍?‍?Widespread use of insecticides to control major outbreaks is not practical because of risk of contaminating salmon-spawning and trout-rearing streams; but insecticide use may be justified in local, high value areas. Weather, diseases, and parasites control outbreaks naturally. Damage-prone stands should be identified and harvested before insect attack or salvage-logged following outbreaks. Ideally, second-growth stands should be managed for resistance to insect pests.