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- This study investigated the feasibility of developing a technique for estimating site index of Douglas-fir in the Pacific Northwest, using aerial photos and topographic maps. Physiographic features were used as indicators of site index. Analysis showed that although most of the features were highly significant as criteria for predicting site index, they explained less than one-third of its variation. Equations, using the physiographic features as independent variables, were shown to be useful for estimating site index by a double-sampling procedure--particularly in relatively inaccessible...AuthorsGrover A. ChoateSourceUSDA Forest Service PNW Old Series Research Paper No. 45: 1-26Year1961
- This report presents the results of a study to determine the degrade (loss in volume and value) of western hemlock lumber cut, kiln-dried, and surfaced in accordance with commercial practice in western Oregon. The study measured (1) loss in volume due to culling and trimming surfaced dry lumber because of sawing, seasoning, and surfacing defects; (2) reduction in grade due to seasoning and surfacing defects; and (3) reduction in grade due to incomplete manufacture or the development of manufacturing defects. Degrade is expressed as a percentage of the rough green lumber volume and also as...AuthorsA.C. Knauss, E.H. ClarkeSourcePNW Old Series Research Note No. 207, p. 1-11Year1961
- Thinning trials on three cooperative experimental forests in western Washington have provided an excellent opportunity to evaluate tree damage resulting from typical thinning operations in young-growth timber. The type and degree of damage can, of course, be expected to strongly affect condition and vigor of the residual stand and ultimate success of a thinning regime.AuthorsNorman P. WorthingtonSourcePNW Old Series Research Note No. 202, p. 1-7Year1961
- This report presents results of a study to determine the degrade (loss in volume and value) of ponderosa pine lumber when cut, kiln-dried, and surfaced in accordance with commercial practice. The study measured (1) loss in volume due to culling and trimming surfaced dry lumber because of sawing, seasoning, and surfacing defects; (2) reduction in grade due to seasoning and surfacing defects; and (3) reduction in grade due to incomplete manufacture or the development of manufacturing defects. Degrade is expressed as a percentage of the rough green lumber volume and also as a loss in value...AuthorsA.C. Knauss, E.H. ClarkeSourcePNW Old Series Research Note No. 205, p. 1-12Year1961
- In the late 193O's, a subalpine grassland in the green fescue type in the Wallowa Mountains of northeastern Oregon was known to be in very poor condition. This grassland, located in the headwaters of the Imnaha River and locally known as Tenderfoot Basin, had been subjected to mismanaged sheep grazing for many years. Both quality and quantity of forage had dwindled until grazing capacity of the basin was only 8 percent of its estimated potential. The area of ground surface covered by vegetation was reduced 75 percent. Accelerated erosion was evident, with soil losses averaging 521 tons per...AuthorsGerald S. StricklerSourcePNW Old Series Research Paper No. 40: 1-46Year1961
- A substantial portion of the commercial forest land in southwestern Oregon is occupied by dense stands of brush species or by understocked stands of conifers with a dense understory of brush. Individual brushfields range in size from small patches a few acres in extent to large, continuous areas covering more than 10,000 acres. Climatically, the area is warmer and drier than the northern portion of the Douglas-fir region; and these conditions are reflected in the character of the shrubby vegetation. Sclerophyllous species with dense, stiff branches and thick, evergreen leaves are far more...AuthorsH.J. GratkowskiSourcePNW Old Series Research Note No. 217, p. 1-18Year1961
- This report summarizes a 1978-79 timber resource inventory of five counties in the Olympic Peninsula of Washington: Clallam, Grays Harbor, Jefferson, Mason, and Thurston. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.AuthorsPatricia M. Bassett, Daniel D. OswaldKeywordsSourceRes. Bull. PNW-RB-093. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 31 pYear1961
- To evaluate effects of different degrees of release on individual Douglas-fir trees, a study was started in 1952 in a 41-year-old, site IV stand at the Wind River Experimental Forest. A remeasurement at the end of four growing seasons showed that dominants respond more quickly and positively to the removal of competing trees than codominants or intermediates. A second remeasurement at the end of seven growing seasons substantiates this initial trend and adds to our understanding of the reaction of Douglas-fir trees to the removal of competitors.AuthorsDonald L. ReukemaSourcePNW Old Series Research Note No. 208, p. 1-4Year1961
- With the advent of increased thinning activity in managed stands of young-growth Douglas-fir (Pseudotsuga menziesii), knowledge of growth and form development of released trees becomes necessary for calculations of total volume and growth. Any appreciable change in the rate of radial increment at various points along the stem of a released tree could cause change in its form and volume. This study was initiated to determine to what extent thinning alters the form of released Douglas-fir trees.AuthorsVern P. YerkesSourcePNW Old Series Research Notes No. 194, p. 1-5Year1960
- Forests of the Pacific Northwest yield a number of secondary or so-called minor forest products. These include those smaller, side-line items of commercial value that can usually be harvested without intensive management or cultivation. They are generally only incidental to a primary use of the land for sawtimber or pulpwood production. In most cases they can be harvested by individuals working alone, without expensive equipment.AuthorsThomas C. AdamsSourcePNW Old Series Research Notes No. 195, p. 1-8Year1960