This publication describes the use of post harvest soil nitrate testing as a tool for assessment of nitrogen (N) management in manured cropping systems west of the Cascade Mountains in Oregon, Washington, and south coastal British Columbia. The first section of this publication gives general information on the test and...
Many nutrients and lime are not mobile in the soil. When applied to the soil surface without tillage, these materials remain in the top 2 inches, especially in production systems that lack tillage. If a soil sample is taken at a standard 8-inch depth, the top 1 to 2 inches,...
Live western larch, Larix occidentalis Nutt., a tree species resistant to the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, produces the monoterpene 3-carene in higher concentrations compared to Douglas-fir, the preferred host of D. pseudotsugae (Reed et al. 1986). The inhibitory effects on attraction to aggregation pheromones and toxicity of 3-carene to...
Upper-stem diameter measurements from a levels-of-growing-stock study on Larix occidentalis in the Blue Mountains of eastern Oregon were collected over a 25 year period with an optical dendrometer. The following hypotheses were tested with these data: 1) stand density regime has a significant effect on stem form; and 2) crown...
Concerns over the possibility of exotic pest
introductions from eastern Russia to the West Coast of the United States due to proposed log imports raises the question of the effectiveness of possible mitigation measures. Toxicity of methyl bromide to representative pathogenic fungi was tested by exposing Armillaria ostoyae, Heterobasidion annosum,...
Second of a planned series of mill studies to test the adequacy of a log grading system for species associated with ponderosa pine, the study reported was made with the cooperation of Stilwell-Pengilley Lumber Company, under the direction of a committee representing participating agencies, namely:
Bureau of Indian Affairs
Bureau...