Red alder (Alnus rubra Bong.) is a common associate and a potentially severe competitor of Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) in the Oregon Coast Range. However, because it fixes nitrogen and increases rates of soil nutrient cycling, red alder has the potential to benefit Douglas-fir. The objective of...
Tanoak (Lithocarpus densflorus (Hook and Am.) Rehd.), an evergreen hardwood tree that grows abundantly in southwest Oregon and
north California, sprouts vigorously after a disturbance, such as logging or fire These sprouts form clumps that can hamper conifer
regeneration on clearcuts and in shelterwoods. In order to obtain a quantitative...
Effects of tanoak (Lithocarpus densiflorus) on early
growth, morphology, and physiology of Douglas-fir
(Pseudotsuga menziesii) were studied to determine
developmental characteristics of young stands and
mechanisms of competition. Growth, leaf area, and biomass
of Douglas-fir, tanoak, and shrubs / herbs were monitored
for six years after establishing a gradient of...
Published April 1981. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The umbrella species concept is a single-species conservation strategy built on the notion that indirect protections are provided for multiple species that occupy the same area as a single, or umbrella, species. The utility of the umbrella species concept relies on similar associations of abundance, distribution, life history requirements, and...
Growing societal demand for forest products is pressuring managers to increase productivity from a finite land area, and it is expected that increased supply will come mostly from expansion of intensively managed stands. The USDA Forest Service and numerous collaborators created the Long-Term Soil Productivity (LTSP) network of research sites...
We evaluated the two-year effects of variable-retention harvest on chipmunk (Tamias spp.) abundance (Nˆ ) and habitat in mature coniferous forests in western Oregon and Washington because wildlife responses to density/pattern of retained trees remain largely unknown. In a randomized complete-block design, six treatments were applied to 13-ha units at...