Treesearch

Chlorogenic acid was identified in the foliage of Douglas-fir during the dormant season. Concentrations varied among genotypes and ranged between 75 and 390 p.p.m. in the fresh tissue.

Total above-ground production was evaluated in 28 natural alder thickets, aged 1 to 14 years. On a per acre basis; mean annual production varied from 3 to more than 20 tons of green wood per acre. Such yields warrant preliminary trials of short-rotation cultural systems with red alder.

The combustion products (smoke) from forest wildfires or prescribed burns are often considered on a par with any other emission that might affect air quality. But enough is known about smoke from woody fuels to indicate that its importance is limited almost entirely to visibility obstruction, an effect that can be minimized by proper timing and preparation for burning. Much of the organic matter in smoke from forest fuels is similar to material normally entering the atmosphere from vegetative life or from the decomposition of vegetative matter. Fire compresses these processes into a...

Forest environments are classified by elevation, temperature, moisture, potential solar radiation, and soil type. Broad elevation classes are derived from topographic maps or altimeter measurements, measured temperature and moisture conditions are related to vegetation by using plant indicator species (illustrated), and tabular values are employed in estimating potential solar radiation. A series key is included for identifying soil types. Future correlations of silvicultural practices with environmental classes will facilitate optimal prescription for each forest environment in the basin.

Increasing demand for timber has put upward pressure on log production levels in Oregon and Washington. Fluctuations in log production result primarily from changes in national demand for wood products. The log production cycle with respect to business conditions has become countercyclical since World War II. During the 1949-69 period, annual changes in housing starts, lagged 1 year, were significantly related to changes in total timber harvest on all ownerships and to changes in National Forest stumpage prices for all species. Annual stumpage price changes were significantly related to...

The distribution of an outbreak population of lodgepole needle miner, Coleotechnites near milleri (Busck), in central Oregon was studied in relation to forest stand and site characteristics. The outbreak occurred primarily in topographic basins where lodgepole pine, Pinus contorta Douglas, grows in pure stands and is the topo-edaphic climax species. Tree defoliation was not continuous but was interrupted by uninfested stands in basin drainage systems and on well-drained slopes. The transition from infested to uninfested stands was usually marked by changes in topography, soils, tree...

In the history of the Pacific Northwest, log production and conversion have been major economic activities. The long-term trends in timber harvesting have been upward, and most of the harvest has come from large old-growth forest inventories. National and international demands for timber have been a major element in putting upward pressure on log production levels. Economic factors and timber characteristics have largely determined the location and magnitude of the timber harvest. In later years, landowner decisions regarding timber inventory levels and the rate of timber inventory...

Washington's 1971 timber harvest of 6.45 billion board feet was nearly the same as the 1970 harvest level. The total timber harvest on public lands increased nearly 4 percent with a 30-percent increase in eastern Washington more than offsetting a 5-percent decline in western Washington. Part of the increase in eastern Washington reflects salvage of a large volume of timber killed by fire in 1970. State lands in the State of Washington increased their production by 120 million board feet (up 20 percent). Other Federal Agencies had a sharp 51-million-board-foot increase in production, and...

Questionnaires as social science tools are used increasingly to study people aspects of outdoor recreation and other natural resource fields. An annotated bibliography including subjective evaluations of each article and a keyword list is presented for 193 references to aid researchers and managers in the design, construction, and use of mail questionnaires.

Direct beam solar radiation is presented in graphical and tabular form for hourly, daily, and yearly values for seven slopes on each of 16 aspects from the Equator to 60 degrees north in 10-degree increments. Theoretical equations necessary for the calculations are given. Solar altitude and azimuth during the day and year are also presented for the same latitude.