Treesearch

Yellow-cedar has been dying across 600 miles of North Pacific coastal rain forest—from Alaska to British Columbia—since about 1880. Thirty years ago, a small group of pathologists began investigating possible biotic causes of the decline. When no biotic cause could be found, the scope broadened into a research program that eventually encompassed the fields of ecology, soils, hydrology, ecophysiology, dendrochronology, climatology, and landscape analysis. Combined studies ultimately revealed that the loss of this culturally, economically, and ecologically valuable tree is caused by a...

We combine a scenario-based, standard-response optimization model with stochastic simulation to improve the efficiency of resource deployment for initial attack on wildland fires in three planning units in California. The optimization model minimizes the expected number of fires that do not receive a standard response--defined as the number of resources by type that must arrive at the fire within a specified time limit--subject to budget and station capacity constraints and uncertainty about the daily number and location of fires. We use the California Fire Economics Simulator to predict...

Forest treatments have the potential to produce significant quantities of forest residue biomass, which includes the tops and limbs from merchantable trees and smaller trees removed to meet management objectives. We spatially analyzed the sensitivity of financially feasible biomass volumes for delivery to a bioenergy facility across 16 combinations of delivered biomass and diesel prices for a 515,900 ha area in western Montana. At the lowest delivered biomass price analyzed, $31.52 per oven dried tonne (ODT), 28% of the potential volume was financially feasible at the lowest diesel price,...

Biomass residue produced by timber harvest operations is estimated for the Olympic and Kitsap Peninsulas, Washington. Scattered residues were sampled in 53 harvest units and piled residues were completely enumerated in 55 harvest units. Production is based on 2008 and 2009 data and is stratified by forest location, ownership type, harvest intensity, and harvest method. An additional sampling was taken to ascertain the mass of wood present in a pile of biomass: 20 piles of biomass were measured for gross volume, processed into hog fuel, and remeasured for volume; five samples were drawn...

This guidebook describes Fox Hollow Research Natural Area (RNA), a 66-ha (163-ac) area that supports dry-site Douglas-fir (Pseudotsuga menziesii)–ponderosa pine (Pinus ponderosa) forest within the Oregon Coast Range ecoregion. Major forest plant associations represented at Fox Hollow RNA include Douglas-fir/salal/western swordfern (Pseudotsuga menziesii/Gaultheria shallon/Polystichum munitum) forest and Douglas-fir/Oregongrape (Pseudotsuga menziesii/Berberis nervosa) forest. Other forested communities are represented within the RNA in minor amounts including: Douglas-fir/poison oak...

Climate change is altering growing conditions in the temperate rain forest region that extends from northern California to the Gulf of Alaska. Longer, warmer growing seasons are generally increasing the overall potential for forest growth in the region. However, species differ in their ability to adapt to changing conditions. For example, researchers with Pacific Northwest Research Station examined forest trends for southeastern and southcentral Alaska and found that, in 13 years, western redcedar showed a 4.2-percent increase in live-tree biomass, while shore pine showed a 4.6-percent...

Analyses of long-term records at 35 headwater basins in the United States and Canada indicate that climate change effects on streamflow are not as clear as might be expected, perhaps because of ecosystem processes and human influences. Evapotranspiration was higher than was predicted by temperature in water-surplus ecosystems and lower than was predicted in water-deficit ecosystems. Streamflow was correlated with climate variability indices (e.g., the El Niño-Southern Oscillation, the Pacific Decadal Oscillation, the North Atlantic Oscillation), especially in seasons when vegetation...

Alaska's boreal forest have experienced unprecedented levels of disturbance. Fire is becoming more frequent and burning larger areas compared to the 1960s and 1970s. In the mid 1990s, insect outbreaks reached epidemic proportions. During the same period, timber harvesting increased to meet demand for logs no longer coming from the Pacific Northwest forest. Alaska white spruce was particularlyaffected by these disturbances, bringing into question the ability of the species to naturally regenerate and reestablish the stands. Andrew Youngblood, a research forester with the Pacifc Northwest...

Establishing markets for ecosystem services—the benefits that nature provides, such as clean air, water, and wildlife habitat—has gained traction in some circles as a way to finance the conservation of these public goods. Market influences on supply and demand work in tandem to encourage ecosystem protection. Jeff Kline and Trista Patterson, scientists with the Pacific Northwest (PNW) Research Station, have identified several criteria needed for ecosystem service markets to achieve their potential. These include regulatory limits on environmental damage, ecosystem services that are...

The logging debris that remains after timber harvest traditionally has been seen as a nuisance. It can make subsequent tree planting more difficult and become fuel for wildfire. It is commonly piled, burned, or taken off site. Logging debris, however, contains significant amounts of carbon and nitrogen—elements critical to soil productivity. Its physical presence in the regenerating forest creates microclimates that influence a broad range of soil and plant processes. Researchers Tim Harrington of the Pacific Northwest Research Station; Robert Slesak, a soil scientist with the Minnesota...