Treesearch

This report summarizes the climatic and hydrologic measurements taken in the High Ridge evaluation area, a four-watershed complex within the Umatilla barometer watershed of eastern Oregon. The information—measurements of water yield; air, soil, and water temperatures; snow depth and density; and wind—is presented to identify the pretreatment condition and is representative of environmental conditions in similar stands within the Blue Mountain area.

Available information on wetwood is presented. Wetwood is a type of heartwood which has been internally infused with water. Wetwood is responsible for substantial losses of wood, energy and production expenditures in the forest products industry. The need to evaluate these losses and to find ways to eliminate or minimize them is emphasized. Because of increased interest in wetwood, excellent opportunities exist in initiating a comprehensive program of research. Both short and long term studies are included in the program with the short-term studies answering the immediate utilization...

Damage occurring from the disease laminated root rot {Phellinus weirii (Murr.) Gilbertson) on two 10-acre plots in a young (40-year-old) stand of Douglas-fir was studied for 25 years. After 25 years, nearly 5 percent of the basal area was killed by the disease. Stand damage caused by vegetative spread of the fungus was significantly related to previous mortality from the disease and to slower net growth during that period. Nonproductive stand openings caused by the disease occupied over 11 percent of one plot and over 7 percent of the other. Although additional losses can be anticipated...

Management of logging residue is becoming an important part of timber sale planning. This involves controlling the amount of residue remaining on the ground and its distribution by diameter size class. Some residue is beneficial. An interdisciplinary team specified a desired residue level for one clearcutting unit of this trial. For comparison another cutting unit was given a specified residue level approximately 30 percent greater, and another unit 30 percent lower.

A recent Forest Survey inventory of western Oregon has been analyzed to determine the extent of physical opportunities to increase wood production through silvicultural treatment. Results are presented by owner group and by geographic unit.

When a western white pine (Pinus monticola Dougl. ex D. Don) tree dies, it undergoes a series of physical changes. The effects of these changes on product recovery are evaluated. Tabular information and prediction equations provide the tools necessary for using this resource.

Housing demand in Japan is analyzed in terms of new household formations, vacancies, and replacements of housing stock. Total number of starts is projected to stay near current levels or decline, depending on assumptions about replacement demands. This contrasts with rapid growth in number of starts during the 1960's and early 1970's.

We compared growth and cone production of Douglas-fir treated 4 years earlier with ISO pounds N per acre applied as urea prill by hand and as a 32-percent N solution applied by helicopter. Nitrogen fertilization increased growth by 3 88 ft per acre during the 4 years after treatment; this 3S-percent gain was similar for both soil (prill) and foliar (solution) applications. Although cone production on the prill-treated plots averaged twofold to fourfold greater than on the control plots, these differences were not statistically significant.

Using nitrogen-fixing plants in forestry becomes financially more attractive as the costs of fertilizers and their application continue to increase. Eight legume cultivars were screened for suitability in Douglas-fir forests of southwest Oregon. The legumes were sown on concurrently fertilized and unfertilized plots within deer exclosures in three logged and burned clearcuts. Percent cover after the first and during the ninth growing season was clearly greater on 2-by 2-meter plots sown with alfalfa, crownvetch, and birds foot deervetch (trefoil) than with wetland deervetch, perennial...

Basal area response to 150 pounds of nitrogen per acre applied as urea or ammonium nitrate was monitored on 1/5-acre plots for 4 years in a recently thinned, 110-year-old, site II, Douglas-fir stand. Nitrogen fertilization significantly increased growth. Basal area increment was increased 59 percent over the controls by ammonium nitrate and 37 percent by urea. The difference in response between urea and ammonium nitrate was statistically significant. Crown class had a highly significant influence on basal area growth of individual trees; however, the increases in growth due to fertilization...