Treesearch

Estimating snag densities in pre-European settlement landscapes (i.e., historical conditions) provides land managers with baseline information for comparing current snag densities. We propose a method for determining historical snag densities in the dry forests east of the Cascade Range. Basal area increase was calculated from tree ring measurements of old ponderosa pine (Pinus ponderosa Dougl. Ex Laws.) trees. Historical stand structure was assumed to be open and parklike, with low densities favoring larger diameter trees, and it was considered relatively stable at the landscape level.

This proceedings is a compilation of 30 articles on various aspects of the management and commercialization of western juniper. The topics are split between commercial and industrial topics, and science and management topics. Presenters were asked to provide abstracts, not full papers, and to include who to contact for more information or a copy of the complete paper, or when and where the information or study was expected to be published.

The Augusta Creek project was initiated to establish and integrate landscape and watershed objectives into a landscape plan to guide management activities within a 7600-hectare (19,000-acre) planning area in western Oregon. Primary objectives included the maintenance of native species, ecosystem processes and structures, and long-term ecosystem productivity in a federally managed landscape where substantial acreage was allocated to timber harvest. Landscape and watershed management objectives and prescriptions were based on an interpreted range of natural variability of landscape conditions...

Knowledge of regional-scale patterns of ecological community structure, and of factors that control them, is largely conceptual. Regional- and local-scale factors associated with regional variation in community composition have not been quantified. We analyzed data on woody plant species abundance from 2443 field plots across natural and seminatural forests and woodlands of Oregon to identify and quantify environmental, biotic, and disturbance factors associated with regional gradients of woody species composition; to examine how these factors change with scale (geographic extent) and...

Phytomass tables are presented for the southeast Alaska archipelago. Average phytomass for each sampled species of tree, shrub, grass, forb, lichen, and moss in 10 forest and 4 nonforest vegetation types is shown.

Genetic parameters from a second generation (F2) disconnected diallel progeny test of the New Zealand radiata pine improvement programme are presented. Heritability estimates of growth and yield traits of 0.2 are similar to progeny test results of the previous generation (F1) generation tests. A trend of declining dominance genetic variance and increasing additive genetic variance with test age was noted. This trend probably represents artifacts affecting early growth of the full sib cross - such as seed size effects or other environmental biases rather than changing gene action.

The forest and agriculture sectors are linked by having a portion of their land bases suitable for use in either sector. A substantial part of the southern land base is suitable for either forestry or agriculture use, with most of forestation on U.S. agriculture land in the South. We examine how land exchanges between forestry and agriculture are influenced by specific federal conservation and farm support policies, including changes in the Conservation Reserve Program. Reallocation of land is a significant part of the sectors' responses to the policies, along with intensification of...

Research interest in the forests of Alaska can be traced from the 1990s back to 1741, when Georg Steller, the surgeon on Vitus Bering's Russian expedition, visited Kayak Island, collected plants, and recorded his observations. Given the scope and scale of potential research needs and relatively high expenses for travel and logistics in Alaska, support for forest research in Alaska, from this first European contact through the present era of scientists working with the U.S. Department of Agriculture, Forest Service, seldom was adequate. Forest Service scientists at Juneau, Fairbanks, and...

New silvicultural prescriptions for ecosystem management on both public and private timberlands in western North America will likely result in an influx of relatively small-diameter sawtimber for processing. Since sawmills currently process a majority of sawtimber harvested in western North America (more than 80% in some regions), this study concentrated on determining the value of small-diameter sawtimber delivered to sawmills. Data were collected during the summer of 1997 to describe a representative random-length sawmill and a representative stud mill for the inland region of the United...

It is commonly expected that self-thinning will maintain small-diameter stands at near-normal densities and allow dominant trees to grow reasonably well. Such self-thinning did not occur in the unthinned plots in a thinning study in the Methow Valley of northern Washington, even though there was some suppression-caused mortality. A shift from suppression-caused mortality to insect-caused mortality took place when quadratic mean diameters (QMDs) reached 7 inches. Thinning to spacings wider than 9.3 feet reduced growth of both basal area and cubic volume per acre but greatly in-creased...