Treesearch

In spring 2006 and 2007, sawmill capacity and wood utilization information was collected for selected mills in southeast Alaska. The collected information is required to prepare information for compliance with Section 705(a) of the Tongass Timber Reform Act. The total estimated design capacity in the region (active and inactive mills) was 289,850 thousand board feet (mbf) Scribner log scale in calendar year (CY) 2005 and 284,350 mbf in CY 2006. The estimated design capacity of active mills was 259,850 mbf for CY 2005 and 247,850 mbf for CY 2006. This is a 2.9-percent decrease in active...

This is a state-of-the-science synthesis of the effects of forest harvest activities on peak flows and channel morphology in the Pacific Northwest, with a specific focus on western Oregon and Washington. We develop a database of relevant studies reporting peak flow data across rain-, transient-, and snow-dominated hydrologic zones, and provide a quantitative comparison of changes in peak flow across both a range of flows and forest practices. Increases in peak flows generally diminish with decreasing intensity of percentage of watershed harvested and lengthening recurrence intervals of...

Population genetics plays an increasingly important role in the conservation and management of declining species, particularly for defining taxonomic units. Subspecies are recognized by several conservation organizations and countries and receive legal protection under the US Endangered Species Act (ESA). Two subspecies of spotted owls, northern (Strix occidentalis caurina) and Mexican (S. o. lucida) spotted owls, are ESA-listed as threatened, but the California (S. o. occidentalis) spotted owl is not listed. Thus, determining the boundaries of these subspecies is critical for effective...

Frequent, low-intensity fires were historically a common feature in many dry forests of the United States. Today, largely owing to fire exclusion and past management practices, many of these fire-dependent forests contain significantly more small trees and fewer large trees than occurred under the natural fire regime. These altered conditions increase the probability of unnaturally severe wildfires, susceptibility to uncharacteristic insect outbreaks, and drought-related mortality. Restoration of these forests is a priority for forest managers throughout the country. Unfortunately, little...

In 1999, the Fall River Long-Term Site Productivity study began in coastal Washington to investigate how intensive management practices affect soil processes and forest productivity. By comparing conventional harvests to more intensive wood removal treatments, researchers are answering long-standing questions about how residual organic matter influences future growth. Also, by using herbicides to control competing vegetation, they are quantifying the influence other vegetation has on tree growth. Finally, they are measuring soil properties and tree growth on plots where the soil was not...

Most ecosystems contain a few common species and many rare ones. By virtue of being rare, these species are often poorly understood and difficult to manage. Scientists at the PNW Research Station have recently published a landmark book that chronicles what is known and what they've recently learned about conserving cryptic biodiversity. For the past decade, federal land managers in the Pacific Northwest have been faced with the unprecedented challenge of ensuring the protection of more than 400 rare or little-knowns species, mostly fungi, lichen, mollusks, and amphibians thought to be...

Although prescribed fire is increasingly being used in ponderosa pine forests as a management tool to reduce the risk of future high-severity wildfire, its effects on wildlife habitat have rarely been examined. The Birds and Burns Network was created to assist managers in planning prescribed fire projects that will reduce fuels and enhance bird habitat. Researchers have established a network of study sites across eight Western States to analyze changes in fuels, downed wood, forest structure, bird habitat, and populations of birds within 1 to 2 years of prescribed fires. Additionally,...

The threat from wildland fire continues to grow across many regions of the Western United States. Drought, urbanization, and a buildup of fuels over the last century have contributed to increasing wildfire risk to property and highly valued natural resources. Fuel treatments, including thinning overly dense forests to reduce fuel and lower fire risk, have become a priority for land managers. Planning fuel treatments on public lands is a complicated problem. Treatments must address multiple management objectives that are often conflicting and burdened with regulatory constraints.

Not all landslides are created equal. Some have the potential to run out to streams and others do not. Some are likely to simplify and damage stream habitat, and others can be important sources of gravel and large wood, fundamental components of habitat complexity for salmon and other stream inhabitants. Forest managers want to avoid negative consequences and promote positive characteristics of debris flows. Until recently, however, approaches to assess whether landslides will enter streams over large areas have been unavailable.

Commercial farming of Atlantic salmon in marine net-pens has become a booming industry. At present, approximately 130 salmon farms exist along the Pacific coast of North America. Most of these farms are in cold marine bays within British Columbia, where farmed salmon have become the province’s most valuable agricultural export. Each year, thousands of farmed Atlantic salmon escape their pens, and could potentially impact native fishes. The PNW Research Station has recently examined the risk of population establishment by escaped Atlantic salmon in the Pacific Northwest, and assessed the...