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Washoe pine, related to ponderosa pine but occurring at higher elevations along the western edge of the Great Basin, crosses freely with the Rocky Mountain race of ponderosa despite evidence of long-term separation. Washoe is morphologically distinct from the parapatric Pacific race of ponderosa pine, and the two taxa are kept separate partly by genetic barriers that reduce seed yield by about two-thirds. Washoe pine most closely resembles North Plateau ponderosa pine, and may be a late-Pleistocene offshoot of this race, which occupies the Pacific Northwest interior.

Two slash prediction handbooks commonly used in California do not use data from California. To test predictions of the handbooks in northeastern California, logging residues from commercially thinned young-growth stands were surveyed. Measured residues were compared to handbook predictions. Species represented were ponderosa pine, California white fir, California red fir, and Douglas-fir. Only for the 3- to 6-inch (7.62- to 15.2-cm) residue size class in ponderosa pine was the mean difference between predicted and measured loadings significantly different from zero. For the forest types...

The linear relationship of inside to outside bark diameter at breast height provides a basis for estimating diameter inside bark from diameter outside bark. Estimates of diameter inside bark and past diameter outside bark are useful in predicting growth and yield. During field seasons 1979-1982, data were obtained from stem analysis of 931 trees in young-growth stands of the mixed-conifer type on the westside Sierra Nevada of California. Species included were coast Douglas-fir, California white fir, incense-cedar, sugar pine, ponderosa pine, and Jeffrey pine. This note provides equations...

Range managers need easily measured indices of dietary quality to ensure high quality forage for deer. Levels of fecal nitrogen and fecal 2,6 diaminopimelic acid, which have been suggested as such indices, were monitored for two herds of black-tailed deer (Odocoileus hemionus columbianus) in northern California. Both values were highest in summer collections, suggesting high quality summer diets, and were lowest in winter collections. Nitrogen levels appeared to differ between herds, but the cause could not be determined. DAPA levels did not appear to differ between herds.

The effects of 20 months of intensive disturbance by humans, as well as the presence of feral hogs Sus scrofa, was measured on vegetation. Both forms of disturbance have been thought severely to affect Hawaiian rain forests by reduction of plant cover and allowing the proliferation of exotic plants. Despite much human use throughout the stud), area, the only significant (P ¡Ü 0.05) effects were within 2 m of a trail. This disturbance was limited to vegetation < 10 cm in height. No change in canopy cover or in incidence of exotic plants was noted. Feral hog usage was approximately three...

We studied dominance behaviors of captive winter flocks of White-throated Sparrows (Zonotrichia albicollis) in central Pennsylvania. Preliminary tests with a small group of birds indicated that there might be differences in behaviors between color morphs if age and sexual differences were controlled. Studies of two larger groups produced considerable variation in results between the groups. One group displayed striking correlations between dominance ability and color. In this group white adult males dominated others more than tan adult males did, whereas tan immature males, adult females,...

Data that represent average worst fire weather for a particular area are used to index daily fire danger; however, they do not account for different locations or diurnal weather changes that significantly affect fire behavior potential. To study the effects that selected changes in weather databases have on computed fire behavior parameters, weather data for the northern Rocky Mountains were treated as probability distributions, then used in computer simulation to estimate distributions of rate-of-spread (ROS) and fireline intensity (FLI). Sensitivity of ROS and FLl to weather input...

The effects of tree spacing and brush competition were evaluated on a ponderosa pine (Pinus ponderosa Dougl. ex Laws. var. ponderosa) site of low productivity in California's North Coast Range. Eleven-year-old saplings were thinned to square spacings of 2.1, 2.4, 3.0, and 4.3 m (7, 8, 10, and 14 ft), and all, half, and none of the understory brush (principally manzanita [Arctostaphylos sp. J) manually removed in a split-plot design. Analysis of variance showed that brush crown cover was significantly related to periodic annual increment in diameter-at-breast-height, height, and volume of...

This report analyzes the procedures used in three regions of the Forest Service, U.S. Department of Agriculture, for selecting the projects that constitute their annual program budget. Personnel at the Southwest (R-3), Pacific Southwest (R-5), and Southern (R-8) Regions were interviewed during September and October 1982. Of special concern was the extent to which analytical methods are used that include an explicit and formal consideration of the relative costs and benefits of alternative program allocations. Current program development and budget processes were found to allow only limited...

Information on the regeneration of Douglas-fir, one of the most valuable timber species in the United States, is summarized, from seed production to care of young stands. General recommendations are given to guide the practitioner. Seed production can be increased by applying fertilizer and by stem girdling. To prepare sites for planting, mechanical, burning, chemical or a combination of treatments should be used. All details during each stage of the planting process should be followed. Steps should be taken to control vegetative competition and animal damage to seedlings and young trees....