Download or read book The Density and Distribution of Sitka Spruce and Western Hemlock Seedling Banks in Partially Harvested Stands in Southeast Alaska written by Louise Simmons Yount Levy Levy and published by . This book was released on 2010 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study's objective was to document and describe the current seedling bank of Sitka spruce (Picea sitchensis (Bong.) Carr.) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) stands in southeast Alaska that were partially cut between 1900 and 1984. We investigated the following: (1) What are seedling bank densities? (2) What are seedling size- and age-class distributions? (3) Do seedbed type, treatment, and understory vegetation affect seedling density and species composition? and (4) What are seedling growth rates? Density was high for both Sitka spruce (22,000 seedlings/ha) and western hemlock (223,000 seedlings/ha) and varied widely between sites. There were always fewer spruce than hemlock. Ninety-five percent of spruce and 94 percent of hemlock were less than 0.5 m tall. Spruce had a mean age of 8 years (range 1 to 41 years) and hemlock 19 years (range 1 to 110 years). Both species were four times as common on logs as on undisturbed forest floor. Under closed-canopy conditions at the 15 sites harvested between 1900 and 1958, the average annual height growth rate was 2.3 cm for hemlock and 1.7 cm for spruce. At the two open-canopy sites, harvested in 1983 and 1984, annual height growth rates increased to 8.2 cm for hemlock and 10.2 cm for spruce. Our results suggest that the seedling bank of both species is established and well stocked, thus providing advanced regeneration for the postharvest stand. Because forest managers have increasing concern about effects of clearcut harvesting in Pacific Northwest forest ecosystems and renewed interest in maintaining or restoring biodiversity, other silvicultural methods warrant examination.
Download or read book Research Paper PNW written by and published by . This book was released on 1978 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Estimation of decay in old growth western hemlock and Sitka spruce in southeast Alaska written by Wilbur A. Farr and published by . This book was released on 1976 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Four year Record of Sitka Spruce and Western Hemlock Seed Fall written by Robert H. Ruth and published by . This book was released on 1955 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plant Succession Following Logging in the Sitka Spruce western Hemlock Forests of Southeast Alaska written by Paul B. Alaback and published by . This book was released on 1984 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Partial Cutting on Stand Structure and Growth and Forest Plant Communities of Western Hemlock Sitka Spruce Stands in Southeast Alaska written by Robert L. Deal and published by . This book was released on 1999 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study evaluated the effects of partial cutting on stand structure and growth, patterns of conifer regeneration, stand mortality and disease, and understory plant diversity and abundance. Seventy-three 1/5 ha plots were established in 18 partially cut stands throughout southeast Alaska. These stands were partially cut 12 to 96 years ago removing 16 to 96 percent of the original stand basal area. Partial cutting resulted in stands that had complex structures and these structures appear similar to uncut old-growth stands. Sitka spruce was maintained over a wide range of cutting intensities, and conversion to hemlock-dominated stands generally did not occur. New spruce regeneration was established in 23 of 55 partially cut plots compared with new spruce found in only 2 of the 18 uncut plots. The current stand basal area, tree species composition, and stand growth were strongly related to trees left after harvest. Trees that were 10 to 70 cm d.b.h. at time of cutting had the greatest tree diameter growth. Little of the stand growth since harvest came from new regeneration or trees greater than 70 cm d.b.h. The diameter growth of residual hemlock and spruce trees were similar The species richness of vascular plants and bryophytes was similar among uncut and partially cut plots and did not significantly change with different cutting intensities. Overall, plant community structures were similar between the uncut and partially cut plots. However, moderate and heavy cutting intensities resulted in stands that had significantly different plant community composition. The abundance of most deer forage plants did not significantly change after partial cutting. It appears that silvicultural systems that use single tree selection or small openings can be successful for timber management purposes in southeast Alaska. Concerns about changing tree species composition, lack of spruce regeneration, greatly reduced stand growth and vigor, increased dwarf mistletoe infection in hemlock trees, and higher incidence of tree wounding, decay, and mortality with partial cuts were largely unsubstantiated. Stand structural diversity, species richness and understory plant abundance were all greater in partially cut stands than in young-growth stands developing after clearcutting.
Download or read book Ripening and Dispersal of a Bumper Western Hemlock Sitka Spruce Seed Crop in Southeast Alaska written by A. S. Harris and published by . This book was released on 1969 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Occurrence of Insect and Disease Pests on Young growth Sitka Spruce and Western Hemlock in Southeastern Alaska written by Susan M. Tait and published by . This book was released on 1985 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Management of Western Hemlock Sitka Spruce Forests for Timber Production written by Robert H. Ruth and published by . This book was released on 1979 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Response of Sitka Spruce and Western Hemlock to Commercial Thinning written by Joseph N. Graham and published by . This book was released on 1985 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cubic foot volume tables and equations for young growth western hemlock and Sitka spruce in southeast Alaska written by Wilbur A. Farr and published by . This book was released on 1976 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Yield of Even aged Stands of Western Hemlock written by George H. Barnes and published by . This book was released on 1962 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Partial Cutting of Western Hemlock and Sitka Spruce in Southeast Alaska written by and published by . This book was released on 1971 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Field Performance in Southeast Alaska of Sitka Spruce Seedlings Produced at Two Nurseries written by John C. Zasada and published by . This book was released on 1990 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tables of Possible Interest to Silviculturists in Southeast Alaska written by Wilbur A. Farr and published by . This book was released on 1985 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecology and Management of Sitka Spruce written by N. Merle Peterson and published by UBC Press. This book was released on 2011-11-01 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sitka spruce, the largest of the world's spruces, is an important component of British Columbia's coastal forests. Its ecology gives it a special place in the sustainable management of the province's forests. However, in west coast forestry it is poorly known in comparison with its main coniferous companions -- Douglas-fir, western redcedar, and western hemlock. As an important international forestry resource, it is crucial that Sitka spruce -- its ecology and the ecosystems in which it occurs -- be clearly understood by those who are involved with its management.
Download or read book Sitka Spruce written by Harold Scofield Betts and published by . This book was released on 1945 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
