Treesearch

Provisional seed zones and breeding zones were developed for white pine (Pinus monticola Dougl. ex D. Don) in the Cascade Range of western Washington and Oregon. Recommendations were based on genetic variation patterns obtained by evaluating genotypes of trees from 115 locations. Genotypes controlling growth vigor and growth rhythm were assessed in common gardens. Five zones, delimited mainly by latitude, were recommended: two in Washington, two in Oregon, and one in both States adjoining the Columbia River.

A long-term study to determine the effects of several methods of timber harvest on the distribution of Rocky Mountain elk (Cervus elaphus nelsoni) was begun in the early 1970's in the Blue Mountains of northeastern Oregon. The study area was an upper slope spruce-fir type with harvest designed to compare changes in elk use, as measured by pellet-group densities under small-patch or large-block clearcuts, partial cuts, and uncut controls. Results showed prescribed logging practices in spruce-fir forests improved forage and habitat diversity for elk. Overall use by elk increased three and...

Forty felled dominant and codominant Pacific silver fir trees (Abies amabilis Dougl. ex Forbes) from 39 locations provided the basis for height-age and site index curves. Trees were from upper slope forests of the Cascade Range in Oregon and Washington. Trees ranged in age from 100 to 300 years and were identified by their height-growth trend as free growing throughout their lives. Twenty additional dominant trees with height growth retarded when they were young were excluded from the site index and height-growth analyses. The early rate of diameter growth of these 20 trees was used to...

Responses of stream chemistry parameters, nitrate-N (NO3-N), phosphate (PO4), calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), and hydrogen ion activity (pH) were measured on 13 wildland watersheds managed at four different grazing strategies. Range management strategies tested were (A) no grazing, (B) grazing without control of livestock distribution (8.2 ha/AUM), (C) grazing with control of livestock distribution (7.7 ha/AUM), and (D) grazing with control of livestock distribution and cultural treatments to improve forage production (2.8 ha/AUM). Nitrate-N, PO4, Ca, Mg, K, and...

Radiotelemetry studies of spotted owl (Strix occidentalis) ranges and habitat-use must be designed efficiently to estimate parameters needed for a sample of individuals sufficient to describe the population. Independent data are required by analytical methods and provide the greatest return of information per effort. We examined time series of relocations and the size, shape, and composition of ranges of nine adult spotted owls in the Oregon Coast Range. Based on two methods of analysis, independent relocations were separated by 3 days in the breeding season and 2-5 days outside the...

A total of 562 white firs (Abies concolor (Gord. & Glend.) Lindl. ex Hildebr.) and red firs (A. magnifica A. Murr.) with logging wounds were felled, dissected, and analyzed for infection and decay in 28 commercially thinned stands on the Klamath and Tahoe National Forests in California. On the Klamath National Forest, decay losses associated with wounds were 1.2 and 5.7 percent of the gross merchantable cubic-foot volume and Scribner board-foot volume, respectively; on the Tahoe National Forest, these volumes were 1.7 and 7.6 percent. Wound area and age were most closely related to extent...

Sitka spruce (Picea sitchensis (Bong.) Carr.) grew an estimated 37 cubic feet of stemwood per acre per year (2.6 m3·ha-1·yr-1) in remnant World War II plantations on Amaknak Island and 38 cubic feet of stemwood per acre per year (2.7 m3·ha-1·yr-1) in an early 19th century grove on Expedition Island, 520 miles (837 km) southwest of natural tree limits in Alaska. Trees in fairly dense plots on Amaknak Island averaged 7 inches (18 cm) in diameter at breast height (d.b.h.) and 21 feet (6.5 m) tall on sheltered sites. The largest trees in the Expedition Island grove were 21.5 inches (54.6 cm)...

This paper instructs resource analysts on use of the Tree Value System (TREEVAL). TREEVAL is a microcomputer system of programs for calculating tree or stand values and volumes based on predicted product recovery. Designed for analyzing silvicultural decisions, the system can also be used for appraisals and for evaluating log bucking. The system calculates results based either on optimized tree bucking or on simulated bucking from user input. Currently, TREEVAL contains data for young-growth Douglasfir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii); however, other species can also...

Data on net primary biological productivity of United States forests are summarized by geographic region. Site factors influencing productivity are reviewed. This paper is a review of existing literature in the productivity of various forest regions of the United States, the influence of site factors on forest productivity, and the impact of various forest-management practices on site productivity.

The results of a statewide inventory of western juniper and pinyon-juniper woodlands are presented. Included are statistics on area of woodland by type and ownership; area of rangeland with scattered juniper and pinyon trees; wood volume by ownership, species, and tree size; juniper fenceposts; tree and stand age distribution; stand characteristics, including overstory and understory; and a discussion of resource potential and changes in western juniper and pinyon-juniper woodland since 1945.