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

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Richard L. Williamson; Frank E. Price
    Date: 1971
    Source: Res. Pap. PNW-RP-117. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 21 p
    Publication Series: Research Paper (RP)
    Station: Pacific Northwest Research Station
    PDF: View PDF  (1.2 MB)

    Description

    Vigorous, mature (post-rotation age) Douglas-fir stands will probably exist for another 50 years or more on some properties in western Oregon and Washington. Intermediate harvests in the form of thinnings were analyzed on nine study areas ranging from 70 to 150 years old when thinned.

    Recoverable cubic-volume growth, averaging 81 percent of normal gross growth, was recorded for up to 38 years with single thinnings and for 18 years with two thinnings. This percentage increases with stand age, but rate of response to thinning decreases with increasing stand age.

    A dramatic 61-percent reduction in loss caused by bark beetles and substantial reductions in losses from windthrow (30 percent), breakage (33 percent), and suppression (46 percent) were measured.

    Reserve basal area may be maintained between 60 and 85 percent of normal. Thinning should follow marking guidelines previously recommended but with more emphasis on crown release since spacing is important in vigorous, mature stands as well as in younger stands.

    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

    Williamson, Richard L.; Price, Frank E. 1971. Initial thinning effects in 70- to 150-year-old Douglas-fir--western Oregon and Washington. Res. Pap. PNW-RP-117. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 21 p

    Keywords

    thinning (trees), forest cutting systems, Douglas-fir, Pseudotsuga menziesii, forest improvement cutting

    Related Search


    XML: View XML
Show More
Show Fewer
Jump to Top of Page
https://www.fs.usda.gov/treesearch/pubs/26236