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- Land management professionals (foresters, wildlife biologists, range managers, and land managers such as ranchers and forest land owners) often have need to evaluate their management activities. Photographic monitoring is a fast, simple, and effective way to determine if changes made to an area have been successful. Ground-based photo monitoring means using photographs taken at a specific site to monitor conditions or change. It may be divided into two systems: (1) comparison photos, whereby a photograph is used to compare a known condition with field conditions to estimate some parameter...AuthorsFrederick C. HallKeywordsSourceGen. Tech. Rep. PNW-GTR-503. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 340 pYear2001
- Predicting sediment production from forest roads is necessary to determine their impact on watersheds and associated terrestrial and stream biota. A method is presented for measuring sediment originating from a road segment for individual storm events and quantifying the delivery to streams. Site selection criteria are listed to describe the characteristics for efficient data collection and analysis. The method describes equip-ment used to quantify sediment transport—data loggers, a rain gage, a traffic counter, Parshall flumes with stilling wells, hydrostatic pressure transducers, and...AuthorsKeith KahklenKeywordsSourceRes. Note PNW-RN-529. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 17 pYear2001
- The effects of partial cutting on plant species richness, community structure, and several understory species that are important for deer forage were evaluated on 73 plots in 18 stands throughout southeast Alaska. These partially cut stands were harvested 12–96 years ago when 16- 96% of the former stand basal area was removed. The species richness and community structure of understory plants were similar in uncut and partially cut plots. However, plots where more than 50% of the basal area was cut had a significantly different plant community structure. Species composition and abundance...AuthorsRobert DealSourceCanadian Journal of Forest Research. 31: 2067-2079Year2001
- The vast forests of the Pacific Northwest region of the United States, an area outlined by the states of Oregon, Washington, and Idaho, are well known or their rich diversity of macrofungi. The forests are dominated by trees in the Pinaceae with about 20 species in the genera Abies, Larix, Picea, Pinus, Pseudotsuga, and Tsuga. All form ectomycorrhizas with fungi in the Basidiomycota, Ascomycota, and a few Zygomycota. Other ectomycorrhizal genera include Alnus, Arbutus, Arctostaphylos, Castinopsis, Corylus, Lithocarpus, Populus, Quercus, and Salix, often occurring as understorey or early-suc...AuthorsR. Molina, D. Pilz, Jane E. Smith, S. Dunham, T. Dreisbach, T. O’Dell, M. CastellanoSourceIn: Moore, D.; Nauta, N.N.; Evans, S.E.; Rotheroe, M. Fungal conservation issues and solutions. Cambridge, UK: Cambridge University Press: 19-63Year2001
- This paper reviews how population size and structure impacts the maintenance of genetic variation in breeding and gene resource populations. We discuss appropriate population sizes for low frequency alleles and point out some examples of low frequency alleles in the literature. Development of appropriate breeding populations and gene resource populations are discussed.AuthorsR. Johnson, B. St. Clair, S. LipowSourceIn: Proceedings ITTO conference on in situ and ex situ conservation of commercial tropical trees: 215-230Year2001
- The adoption of ecosystem-based management strategies focuses attention on the need for broad scale estimates of ecological conditions; this poses two challenges for the science community: estimating broad scale ecosystem conditions from highly disparate data, often observed at different spatial scales, and interpreting these conditions relative to goals such as sustainability. The Interior Columbia Basin Ecosystem Management Project (ICBEMP), estimated relative composite ecological integrity by clustering conditions among proxy variables representing three component integrity ratings...AuthorsThomas M. Quigley, Richard Haynes, Wendel J. HannKeywordsSourceForest Ecology and Management. 153: 161-178Year2001
- A spruce beetle outbreak of unprecedented size and intensity killed most of the spruce trees on millions of acres of forest land in south-central Alaska in the 1990s. The tree mortality is affecting every component of the ecosystem, including the socioeconomic culture dependent on the resources of these vast forests. Based on information obtained through workshops and outreach to resource managers and diverse stakeholders, we have developed priority issues for restoring the land. Wildfire is a major issue, particularly for the wildland-urban interface areas around Anchorage and on the...AuthorsDarrell W. Ross, Gary E. Daterman, Jerry L. Boughton, Thomas M. QuigleyKeywordsSourceGen. Tech. Rep. PNW-GTR-523. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 38 pYear2001
- Myrtle Island Research Natural Area, an 11.3-ha island in the Umpqua River Valley of the Oregon Coast Range, was established in 1951 to preserve an old-growth stand of Umbellularia californica and scattered old-growth Pseudotsuga menziesii. This floristic study documented 363 specific and infraspecific taxa in 237 genera and 78 families. Of these species, 155 (42.7 percent) are naturalized exotics. Seventeen exotic or native species are listed as noxious weeds in Oregon. Vascular plants include 4 Equisetophyta, 8 Polypodiophyta, 2 Pinophyta, and 349 Magnoliophyta; 328 are annual, biennial,...AuthorsRalph L. ThompsonKeywordsSourceGen. Tech. Rep. PNW-GTR-507. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 27 pYear2001
- The Puget Trough population of Washington’s state-threatened western gray squirrel is centered in Oregon white oak ecotones adjacent to conifer forests and prairies on the Fort Lewis Military Reservation. Our goal was to determine the current status of western gray squirrels in this region. In 1998, we found five western gray squirrels in 538 hours of foot surveys in 133 oak sites. In 1999, we expanded our survey effort and included surveys on foot, surveys with simulated squirrel calls, live trapping, and bait stations with motion-sensitive cameras. No western gray squirrels were detected...AuthorsR. Bayrakci, A.B. Carey, Todd M. WilsonSourceNorthwest Science. 75(4): 333-341.Year2001
- Among the legacies of the Vashon Glaciation are Oregon white oak (Quercus garryana), prairie, wetland, and Douglas-fir (Pseudotsuga menziesii) communities arrayed in a mosaic in the Puget Sound Area (PSA). Much of this mosaic has been destroyed. The largest remaining portion is on Fort Lewis Military Reservation. We examined oak communities on Fort Lewis to assess encroachment by exotic plants and by Douglas-fir, to determine amounts of regeneration of oak and other tree species, and to compare oak community diversity with that of nearby Douglas-fir forests and glacial till prairies. For...AuthorsD.R. Thysell, A.B. CareySourceNorthwest Science. 75(3): 219-235Year2001