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- Silvicultural knowledge and practice have been evolving in the Pacific Northwest for nearly a century. Most research and management activities to date have focused on two major topics: (1) methods to regenerate older, naturally established forests after fire or timber harvest; and (2) growth and management of young stands. Today forest managers can reliably regenerate the major conifer and hardwood species under most conditions by using combinations of natural and artificial regeneration. They also can control stand density and species composition and growth of individual trees, thereby...AuthorsR.O. Curtis, D.S. DeBell, C.A. Harrington, D.P. Lavender, J.B. St. Clair, J.C. Tappeiner, J.D. WalstadKeywordsSourceGen. Tech. Rep. PNW-GTR-435. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 123 pYear1998
- Experimental prescriptions compare agroforestry systems designed to increase financial returns from high-elevation stands in the southern Oregon Cascade Range. The prescriptions emphasize alternative approaches for joint production of North American matsutake mushrooms (also known as North American pine mushrooms; Tricholoma magnivelare) and high-quality timber. Other agroforestry byproducts from the system are ornamental conifer boughs, pine cones, and Christmas trees. Management practices concentrate on increasing the physiological efficiency and vigor of trees, and on altering leaf area...AuthorsJames F. WeigandKeywordsSourceGen. Tech. Rep. PNW-GTR-424. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 42 pYear1998
- A fire behavior module was developed for the California Fire Economics Simulator version 2 (CFES2), a stochastic simulation model of initial attack on wildland fire used by the California Department of Forestry and Fire Protection. Fire rate of spread (ROS) and fire dispatch level (FDL) for simulated fires "occurring" on the same day are determined by making coordinated draws from compound distributions characterizing 2 PM fire behavior indices such as ROS, then adjusting these draws using diurnal adjustment coefficients derived from hourly fire weather observations. Statistical examination...AuthorsJ. Keith Gilless, Jeremy S. FriedKeywordsSourceForest Science. 45(4): 492-499Year1998
- This bibliography updates the list of publications, abstracts, theses, and unpublished reports included in "Research Publications of the H.J. Andrews Experimental Forest, Cascade Range, Oregon, 1948 to 1986" (General Technical Report PNW-GTR-201) and "Research Publications of the H.J. Andrews Experimental Forest, Cascade Range, Oregon: 1988 Supplement" (General Technical Report PNW-GTR-223). Citations are referenced under appropriate keywords.AuthorsDonald L. Henshaw, Sarah Greene, Tami LowryKeywordsSourceGen. Tech. Rep. PNW-GTR-427. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 94 pYear1998
- 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.AuthorsRichy J. Harrod, William L. Gaines, William E. Hartl, Ann CampKeywordsSourceGen. Tech. Rep. PNW-GTR-428. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 16 pYear1998
- 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.AuthorsScott Leavengood, Larry Swan, eds.KeywordsSourceGen. Tech. Rep. PNW-GTR-432. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 97 pYear1998
- 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...AuthorsJohn H. Cissel, Frederick J. Swanson, Gordon Grant, Deanna H. Olson, Gregory V. Stanley, Steven L. Garman, Linda R. Ashkenas, Matthew G. Hunter, Jane A. Kertis, James H. Mayo, Michelle D. McSwain, Sam G. Swetland, Keith A. Swindle, David O. WallinKeywordsSourceGen. Tech. Rep. PNW-GTR-422. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 82 pYear1998
- 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...AuthorsJ.L. Ohmann, T.A. SpiesKeywordsSourceEcological Monographs. 68(2): 151-182Year1998
- 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.AuthorsBert R. MeadSourceRes. Pap. PNW-RP-505. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 48 pYear1998
- 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.AuthorsJ.N. King, M.J. Carson, G.R. JohnsonKeywordsSourceSilvae Genetica. 47(2-3): 80-87Year1998