Treesearch

Releases of Diadegma laricinellum (Hymenoptera: Ichneumonidae), Dicladocerus westwoodii, Dicladocerus japonicus, Chrysocharis laricinellae, Elachertus argissaj, Necremnus metalarus (Hymenoptera: Eulophidae), and Agathis pumila (Hymenoptera: Braconidae) for biological control of the larch casebearer in Oregon, Idaho, and Pennsylvania included some newly imported stocks and additional release locations. More than 14,000 parasites were released at eight sites.

The concept of regional demand is described and applied to the demand for National Forest stumpage. Specifically, demand functions for stumpage (price-quantity relationships) are developed by decade for the major National Forest Regions. The' demand functions are consistent with the 1980 timber program prepared under requirements of the Renewable Resources Planning Act of 1974 (RPA) and provide forest planners with a mechanism to relate National Forest Regional harvest levels to prices.

Seedlings of Pseudotsuga menziesii (Mirb.) Franco, Abies procera Rehd., and Picea sitchensis (Bong.) Carr. were grown for 5 months in growth rooms which simulated hot, warm, or cool growing regimes in greenhouses in western Oregon. Temperature, humidity, light intensity, and photoperiod were changed diurnally and seasonally. In all three species, maximum heights of seedlings were attained in the hot regime, whereas stem diameters were similar under the hot and warm regimes. Dry weight increment was greatest in the warm regime. The cool regime was suboptimal for all aspects of growth....

Diameter, height and volume growth, and yield of thinned and unthinned plots are given for a suppressed, 47-year-old stand of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) in the Methow Valley of northern Washington that averaged about 3 inches in diameter and 23 feet tall before thinning. Considerations are discussed for choosing tree spacing in a precommercial thinning.

Five timber sales were made in old-growth Douglas-fir with matched cutting units. On one unit of each sale uphill falling by either hydraulic jacks or tree-pulling machine was required; on the other unit free falling was required. Logging equipment and methods were the same in each unit. Uphill falling produced a larger volume of timber at less cost than free falling because breakage was less.

Competition for National Forest timber was examined in the Northern, Pacific Southwest, and Pacific Northwest Regions of the Forest Service, U.S. Department of Agriculture. The impacts of sealed bidding and the Small Business Set-Aside Program were found to vary widely among the different appraisal zones. Noncompetitive sales were screened for collusive activity; and in general, little indication was found of such activity.

The most recent information on forest area in California, volume of timber, ownership of forest resources, and rate of use and replenishment is summarized. An analysis of physical opportunities to increase timber production is presented, along with a discussion of problems relating to timber production. Also included are detailed statistical tables; a brief historical sketch of California forestry; a profile of the State's forest industry; a discussion of past, present, and future timber harvest; and a brief summary of nontimber forest resources.

The 40-year succession of a depleted green fescue (Festuca viridula) sub-alpine grassland in the Wallowa Mountains, Oregon, was influenced by historic soil erosion. Range conditions of the grassland annually grazed by domestic sheep improved greatly between 1938 and 1978; most of the improvement occurred between the 30th and 40th years. Photographs illustrate the changes.

One of the first range research programs on National Forest lands was conducted by Dr. Arthur W. Sampson in the Wallowa Mountains, Oregon, between 1907 and 1911. This paper reviews the historical perspective of and the basic range management principles and practices developed from Sampson's studies as well as the land and grazing management of the study area to 1980. Plant succession and range improvement from the depleted conditions prevalent in 1907 are discussed and documented by photographs between 1955 and 1976.

A hierarchical system, with five levels of resolution, is proposed for classifying Alaska vegetation. The system, which is agglomerative, starts with 415 known Alaska plant communities which are listed and referenced. At the broadest level of resolution the system contains five formations - forest, tundra, shrubland, herbaceous vegetation, and aquatic vegetation.