Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

 Due to a lapse in federal funding, this USDA website will not be actively updated. Once funding has been reestablished, online operations will continue.


  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Louise S.Y. Levy; Robert L. Deal; John C. Tappeiner
    Date: 2010
    Source: PNW-RP-585. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 20 p.
    Publication Series: Research Paper (RP)
    Station: Pacific Northwest Research Station
    PDF: View PDF  (1.68 MB)

    Description

    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.

    Publication Notes

    • You may send email to pnw_pnwpubs@fs.fed.us to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

    Citation

    Levy, Louise S.Y.; Deal, Robert L.; Tappeiner, John C. 2010. The density and distribution of Sitka spruce and western hemlock seedling banks in partially harvested stands in southeast Alaska. Res. Pap. PNW-RP-585. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 20 p.

    Cited

    Google Scholar

    Keywords

    Natural regeneration, seedling banks, Sitka spruce, western hemlock, southeast Alaska, partial cutting

    Related Search


    XML: View XML
Show More
Show Fewer
Jump to Top of Page
https://www.fs.usda.gov/treesearch/pubs/35918