Skip to Main Content
True fir spacing trials: 10-year results.Author(s): Robert O. Curtis
Source: Gen. Tech. Rep. PNW-GTR-749. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 36 p
Publication Series: General Technical Report (GTR)
Station: Pacific Northwest Research Station
View PDF (1.34 MB)
DescriptionEighteen precommercial thinning trials were established in true fir-hemlock stands in the Olympic Mountains and the west side of the Cascade Range during the period 1987 through 1994. This paper updates a previous report, with results for the first 10 years after establishment. Results are given for (1) all trees, (2) the largest 80 per acre of any species, and (3) those noble fir (Abies procera Rehd.) and Pacific silver fir (Abies amabilis Dougl. ex Forbes) included in the largest 80 per acre. Diameter growth of all species increased with increase in spacing. Height growth of Pacific silver fir decreased with increase in spacing. The largest 80 trees per acre of all species showed some increase in diameter and basal area growth with increased spacing, while height growth declined slightly and volume growth was nearly constant. Over time, these installations will provide a unique source of information on early development of managed stands of these species, for which little information is now available.
- You may send email to email@example.com 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.
CitationCurtis, Robert O. 2008. True fir spacing trials: 10-year results. Gen. Tech. Rep. PNW-GTR-749. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 36 p
KeywordsTrue firs, Abies procera, Abies amabilis, precommercial thinning, spacing, noble fir, Pacific silver fir
- True fir spacing and yield trials—20-year update
- Dwarf mistletoe in red and white firs in California–23 to 28 years after inoculation
- Shelterwood regeneration of true fir: conclusion after 8 years
XML: View XML