Treesearch

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...

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...

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.

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...

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...

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,...

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...

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...

Squirrel communities simultaneously composed of abundant populations of Glaucomys, Tamias, and Tamiasciurus are: (1) a result of high production of seeds and fruiting bodies by forest plants and fungi and complexity of ecosystem structure, composition, and function; (2) indicative of high carrying capacity for vertebrate predators and (3) characteristic of old, natural forests in the Pacific northwest, USA. I hypothesized that silvicultural manipulation of canopies of second-growth forests could result in spatial heterogeneity that would reproduce the biocomplexity and plant-fungal...

Small mammals have been proposed as indicators of sustainability in forests in the Pacific Northwest and elsewhere. Mammal community composition and species abundances purportedly result from interactions among species, forest-floor characteristics, large coarse woody debris, understory vegetation, and overstory composition. Coarse woody debris is thought to be particularly important because of its diverse ecological functions; covers from 10 to 15% have been recommended based on retrospective studies of forests and small mammals. Unfortunately, ecological correlations are not necessarily...