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- This document outlines an iterative process for assessing the information needs for all Northwest Forest Plan (NWFP) survey and manage species, designing and implementing strategic surveys (including field surveys and other information-gathering processes), and analyzing that information for use in the NWFP annual species review and adaptive-management processes. The framework outlines a series of steps that provide guidance for development of (1) priority information needs, (2) evaluation and selection of information-gathering approaches, (3) implementation of annual work plans, and (4)...AuthorsRandy Molina, Dan McKenzie, Robin Lesher, Jan Ford, Jim Alegria, Richard CutlerSourceGen. Tech. Rep. PNW-GTR-573. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 34 pYear2003
- National and regional interest in the distribution and trends of forest habitat structure and diversity have placed demands on forest inventories for accurate stand-level data. a primary need in the coastal Pacific Northwest of the United States is information on the extent and rate of development of mature forest structure. The objective of this study was to evaluate alternative sampling schemes within a standard national cluster plot design able to efficiently determine density of large live trees and snags, tree mortality, and tree species richness. a simulation approach used stem maps...AuthorsAndrew GrayKeywordsSourceForest Ecology and Management. 175: 1-16Year2003
- National forest inventories were projected in a study that was part of the 2000 USDA Forest Service Resource Planning Act (RPA) timber assessment. This paper includes an overview of the status and structure of timber inventory of the National Forest System and presents 50-year projections under several scenarios. To examine a range of possible outcomes, results are shown for five removals scenarios that incorporate assumptions from both current and past studies of wood flows and harvesting on national forests. In addition, two projections were developed to examine the effects of volume...AuthorsJohn Mills, Xiaoping ZhouKeywordsSourceGen. Tech. Rep. PNW-GTR-568. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 58 pYear2003
- Site index equations and mean annual increment equations used by the Forest Inventory and Analysis Program at the Portland Forestry Sciences Laboratory, Pacific Northwest Research Station, Forest Service, U.S. Department of Agriculture. The equations are for 24 tree species in California, Oregon, and Washington.AuthorsErica Hanson, David L. Azuma, Bruce HiseroteSourceRes. Note PNW-RN-533. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 24 pYear2003
Kudzu (Pueraria montana) community responses to herbicides, burning, and high-density loblolly pine.
Kudzu is an aggressive, nonnative vine that currently dominates an estimated 810,000 ha of mesic forest communities in the eastern United States. To test an integrated method of weed control, abundances of kudzu and other plant species were compared during 4 yr after six herbicide treatments (clopyralid, triclopyr, metsulfuron, picloram 1 2,4-D, tebuthiuron, and a nonsprayed check), in which loblolly pines were planted at three densities (0, 1, and 4 seedlings m22) to induce competition and potentially delay kudzu recovery. This split-plot design was replicated on each of the four kudzu-dom...AuthorsTimothy B. Harrington, Laura T. Rader-Dixon, John W. Jr. TaylorKeywordsSourceWeed Science. 51: 965–974Year2003- Not all forests with old trees are scientifically defined as old growth. Among those that are, the variations are so striking that multiple definitions of old-growth forests are needed, even when the discussion is restricted to Pacific coast old-growth forests from southwestern Oregon to southwestern British Columbia. Scientists understand the basic structural features of old-growth forests and have learned much about habitat use of forests by spotted owls and other species. Less known, however, are the character and development of the live and dead trees and other plants. We are learning...AuthorsValerie RappKeywordsSourceScience Update 4. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 12 pYear2003
- Today, as in the past, complex forces of nature intersect with communities and society. Fire, climate change, invasive species, and large-scale shifts in forest cover and use are some of the key issues society currently faces. This accomplishment report encapsulates a year’s work from our scientists. This work is often interdisciplinary, long term, geographically broad, and policy oriented. And most of all, we strive to make it relevant to the issues of today as we build a foundation for addressing issues of the future.AuthorsValerie RappKeywordsSourceScience Accomplishments Report. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 74 pYear2003
- A 20-year program of research suggests that old-growth forests are ecologically unique and highly valued by people, that naturally young forests with legacies from old forests sustain many, if not all, the higher organisms associated with old growth, but that many managed forests are impoverished in species. Thus, restoring landscape function entails restoring function to managed stands. Managing processes of forest development, not just providing selected structures, is necessary to restore function and biodiversity. Systems of reserves and riparian corridors that do not take into account...AuthorsA.B. CareySourceForestry. 76(2): 221-230Year2003
- A baseline assessment of forest resources in southeast Alaska was made by using a single-phase, unstratified, systematic-grid sample, with ground plots established at each grid intersection. Ratio-of-means estimators were used to develop population estimates. Forests cover an estimated 48 percent of the 22.9-million-acre southeast Alaska inventory unit. Dominant forest types are the western hemlock-Sitka spruce, mixed conifer, and western hemlock types. The timberland portion of productive forest land for all owners is estimated to be 4.1 million acres. Net volume on timberland was...AuthorsWillem W.S. van HeesSourceRes. Pap. PNW-RP-557. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 96 pYear2003
- Dusky Canada geese compose one of the smallest populations of geese in North America and have exhibited a marked decline in the past 30 years. A comprehensive synthesis of past and current biological information on the subspecies has been compiled to provide insights into the ecology and demography of the population, as well as explore management efforts to promote long-term conservation. Duskys occupy a discrete range, which has allowed the development of focused, long-standing management programs. The 1964 Alaska earthquake set in motion significant ecological changes in wetlands, plant...AuthorsRobert G. Bromley, Thomas C. RotheKeywordsSourceGen. Tech. Rep. PNW-GTR-591. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 79 pYear2003