Download (PDF 2.87 MB): https://research.fs.usda.gov/download/treesearch/26254.pdf
Abstract
Public and private agencies are cooperating in a study of eight thinning regimes in young Douglas-fir stands. Regimes differ in the amount of basal area allowed to accrue in growing stock at each successive thinning. All regimes start with a common level-of-growing-stock which is established by a conditioning thinning. Thinning interval is controlled by height growth of crop trees, and a single type of thinning is prescribed. Nine study areas, each involving three completely random replications of each thinning regime and an unthinned control, have been established in western Oregon and Washington, U.S.A., and Vancouver Island, Canada. Site quality of these areas varies from I through IV. Climatic and soil characteristics for each area and data for the stand after the conditioning thinning are described briefly.
Citation
Bell, John F.; Berg, Alan B. 1972. Levels-of-growing-stock cooperative study on Douglas-fir: report no. 02The Hoskins Study, 1963-1970. Res. Pap. PNW-RP-130. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 24 p