Treesearch

A sampling method was derived whereby budworm density can be estimated by the frequency of occurrence of larvae over a given threshold number instead of by direct counts on branch samples. The model used for converting frequencies to mean densities is appropriate for nonrandom as well as random distributions and, therefore, is applicable to all population densities of budworm. The method is suggested as a possible alternative to the direct counting of larvae in lower crown sampling.

A northeast Washington collection of western larch seeds was stratified for 0,10, 20, 40, and 80 days and incubated at 55, 64, and 73 °F. The germination percentage of filled seeds and speed and uniformity of germination were improved by long stratification, particularly at the lowest incubation temperature. Stratified seeds were also nursery sown in early April and May. Emergence occurred when mean air temperatures were low (48-54 °F), which indicated that long stratification should be beneficial in the nursery. First-year seedling height was closely related to date of emergence.

Projections of Alaska timber products output and timber harvest by owner were developed by using a detailed, trend-based analysis. Historical data for 1965-88 were the basis for projections for 1989-2010. Projections of timber products output for each major product (export logs, sawn wood, and market pulp) were used to compute the derived demand for timber. The assumptions these projections depend on include the level of harvest by Alaska Native corporations, sawn-wood consumption in Japan, and exports of market pulp. Potential harvest from Alaska National Forests (primarily the Tongass...

Natural regeneration was abundant, regardless of grazing and grass seeding treatments,after shelterwood cutting to three overstory densities (27, 73, and 119 square feet of basal area per acre) in mixed conifer stands in the Starkey Experimental Forest and Range in eastern Oregon. After 6 years, the number of tree seedlings ranged from about 3,800 per acre on the low-density plots to 39,000 per acre on the highdensity plots and consisted of about 84 percent grand fir (Abies grandis (Dougl. ex D. Don) Lindl.); 10 percent Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco); and...

Seasonal trends of soil water content in plots of snowbrush (Ceanothus velutinus Dougl.), orchard grass (Dactylis glomerata L), and pinegrass (Calamagrostis rubes- cens Buckl.) and in bare plots were measured on a burned-over forest watershed in north-central Washington. A comparison of soil water contents at depths of 12, 24, 36, and 48 inches indicated that the grasses and snowbrush generally used similar amounts of soil water; although during midsummer, water content at 12 inches in - pinegrass plots was significantly lower than that in snowbrush plots, which indicated greater water use...

The state-of-the-art of forest inventory methodology, being closely integrated with the fast-moving, high technology computer world, has been changing at a rapid pace over the past decade. Several successful conferences were held during the 1980s with the goal and purpose of staying abreast of such change. This symposium was conceived, not just with the idea of helping make professional and technical forest mensurationists and managers aware of these changes, but also to give participants hands-on workshop experience with mensurational and inventory problems by using these latest techniques...

Methods of locating pileated woodpeckers (Dryocopus pileatus) are described, including imitating pileated woodpecker vocalizations, identifying nest and roost trees, and finding foraging signs. Populations of pileated woodpeckers can be monitored by using (1) density of breeding pairs, (2) reproduction, and (3) presence or absence of birds. The size of area being monitored, the amount of resources available for the work, and the amount of information desired determine which monitoring method is appropriate.

Hypothesis testing for differences in growth responses among physiographic strata, thinning levels, and fertilizer dosage levels resulted in a set of empirical models for predicting volume increment response of even aged coastal Douglas-fir to nitrogen fertilizer. Absolute and percent responses are estimated for stands both thinned and unthinned, as a function of dosage levels and physiographic provinces. Although not "highly" significant, the physiographic factor was retained in the models for purposes of refinement.

A study of nursery stock performance was conducted on four sites in the Tongass National Forest in southeastern Alaska: two sites at Fire Cove (Ketchikan Ranger District [R.D.]) and one each at Anita Bay (Wrangell R.D.) and Eight Fathom (Hoonah R.D.). Containerized Sitka spruce seedlings used in the study were grown at USDA Forest Service nurseries in Petersburg, Alaska, and Coeur d'Alene, Idaho, from seed sources appropriate for each of the three locations. Seedlings from the Petersburg nursery were taller (33 centimeters versus 18 centimeters) and had greater shoot dry weights (1.51...

Information is needed on the great gray owl to understand its ecology and to consider this species in land management decisions. From 1982 to 1988, we studied 24 pairs and 107 juvenile great gray owls in northeastern Oregon. Forty-nine nests were located; 16 were used more than once, so we observed 71 nesting attempts. Seventy-eight percent of these nesting attempts were successful in raising 1 to 5 young (mean = 2.2). The nests were on stick platforms, on top of broken-off dead trees, and on artificial wooden platforms. Nest trees occurred in a variety of habitats, although most were in...