Treesearch

The distribution of a forest decline of yellow-cedar (Callitropsis nootkatensis (D. Don) Örsted) has been documented in southeast Alaska, but its occurrence in British Columbia was previously unknown. We conducted an aerial survey in the Prince Rupert area in September 2004 to determine if yellow-cedar forests in the North Coast Forest District of British Columbia were experiencing a similar fate as in nearby Alaska. Numerous large areas of concentrated yellow-cedar mortality were found, extending the known distribution of the decline problem 150 km south of the Alaska-British Columbia...

Field studies in Argentina's Yunga District revealed Alpova austroalnicola sp. nov., a hypogeous fungus associated with Alnus acuminata ssp, acuminata. Morphological and molecular studies based on amplification and sequencing of the nuclear LSU rDNA gene showed its unique identity within Alpova. Related genera included in the analyses were Boletus edulis, Rhizopogon spp., Suillus luteus and Truncocolumella citrina. Additional observations of animal diggings around the sites and microscopic examination of fecal pellets of the nine-banded armadillo (Dasypus novemcinctus novemcinctus)...

We evaluated the effectiveness of natural color aerial photography as a tool to improve detection, monitoring, and mapping of sulfur cinquefoil (Potentilla recta L.) infestations. Sulfur cinquefoil is an exotic perennial plant invading interior Pacific Northwest rangelands. Because sulfur cinquefoil produces distinctive pale yellow flowers, we timed aerial photography for early July, when the plant was at peak bloom. Photography was collected at 3 spatial scales (1:3 000, 1:6 000, and 1:12 000). A grid with 250-m spacing was superimposed over photographs of the entire study area using...

This publication presents highlights of a recent south-central Alaska inventory conducted by the Pacific Northwest Research Station Forest Inventory and Analysis Program (USDA Forest Service). South-central Alaska has about 18.5 million acres, of which one-fifth (4 million acres) is forested. Species diversity is greatest in closed and open Sitka spruce forests, spruce woodlands, closed tall alder shrub type, and low shrub willow type. Of the forest land, 1.9 million acres are classified as timberland (unreserved productive forest land). About 1.3 million acres of forest land are reserved...

Relative abundance, survival, home range, and habitat use of snowshoe hares (Lepus americanus) were evaluated in five precommercial thinning treatments in lodgepole pine (Pinus contorta Dougl. ex Loud.) stands in northeastern Oregon between June 2000 and July 2003. A combination of track surveys, trapping grids, and radiocollared hares was used to evaluate these characteristics. Relative abundance of snowshoe hare tracks was highest in unthinned control stands and lowest in the recently thinned stands. The highest abundance of snowshoe hares in trapping grids occurred in patch cuts...

The Pacific Northwest encompasses a range of hydrologic regimes that can be broadly characterized as either coastal (where rain and rain on snow are dominant) or interior (where snowmelt is dominant). Forest harvesting generally increases the fraction of precipitation that is available to become streamflow, increases rates of snowmelt, and modifies the runoff pathways by which water flows to the stream channel. Harvesting may potentially decrease the magnitude of hyporheic exchange flow through increases in fine sediment and clogging of bed materials and through changes in channel morpholog...

This study examined the fluvial transport of invertebrates (aquatic and terrestrial) and coarse organic detritus from forested - headwaters in alternatives-to-clearcutting (ATC) harvest units to aquatic habitats downstream in the coastal mountains of southeastern Alaska. Fifty small streams (mean discharge 2.7 Ls-1, range 0.1-128.1 Ls-1) representing three geographic areas (ATC installations) throughout southeastern Alaska were sampled with 250 µm nets three times per year (April, July, September). Samples were used to assess the subsidy of energy from fishless headwaters to downstream...

Planning activities over large landscapes poses a complex of challenges when trying to balance the implementation of a conservation strategy while still allowing for a variety of consumptive and nonconsumptive uses. We examine a case in southeast Alaska to illustrate the breadth of these challenges and an approach to developing a science-based resource plan. Not only was the planning area, the Tongass National Forest, USA, exceptionally large (approximately 17 million acres or 6.9 million ha), but it also is primarily an island archipelago environment. The water system surrounding and...

Effective natural resources management requires knowledge of the character of resources and of interactions between resource components. Estimates of forest and other vegetation resources are presented to provide managers with information about the character of the resource. Slightly less than half (48%) of southeast Alaska has some type of forest land cover, about 29% has nonforest vegetation, and the remaining 33% is barren or water. Most forest land (85%) and nonforest vegetation (77%) is managed by the U.S. Forest Service, Alaska Region (Region 10), Tongass National Forest. Estimates...

Since the early 1970s, social science research has addressed issues concerning the nature and distribution of values and uses associated with natural resources. In part, this research has tried to improve our understanding of interconnections between resource management and social and cultural chahge on the Tongass National Forest in southeast Alaska. In 1997, scientists at the Pacific Northwest Research Station (PNW) initiated a number of social science studies in response to information gaps identified while developing the Tongass Land Management Plan. Results presented here summarize...