Treesearch

The US Department of Agriculture Forest Service’s focus on hazardous fuels reduction has increased since the adoption of the National Fire Plan in 2001. However, appropriations for hazardous fuels reduction still lag behind wildfire suppression spending. Offsetting fuels treatment costs through biomass utilization or by using innovative administrative mechanisms such as stewardship contracting are two approaches to stretching appropriated dollars further across the landscape. We use fuels treatment data (n=8,451 locations) to ask how wood-processing infrastructure influences where and how...

Disturbance can both initiate and shape patterns of secondary succession by affecting processes of community assembly. Thus, understanding assembly rules is a key element of predicting ecological responses to changing disturbance regimes. We measured the composition and trait characteristics of plant communities early after widespread wildfires in Alaska to assess how variations in disturbance characteristics influenced the relative success of different plant regeneration strategies. We compared patterns of post-fire community composition and abundance of regeneration traits across a range...

We evaluated the abundance of riparian gastropod communities along headwater streams and their response to logging in southwestern Washington State. Terrestrial mollusks near logged streams with ~15 m fixed-width buffers were compared to logged streams with no buffers and to unlogged controls. Mollusk communities varied among sites relative to vegetative composition, the amount of understory cover and presence of seeps or small wetland features in the riparian areas. After logging, slug and snail abundance were significantly different between streams with no buffers compared to fixed-width...

As part of a recent synthesis addressing fuel management in dry, mixed-conifer forests we analyzed more than 5,000 Forest Inventory and Analysis (FIA) plots, a probability sample that represents 33 million acres of these forests throughout Washington, Oregon, Idaho, Montana, Utah, and extreme northern California. We relied on the BioSum analysis framework that integrates several models to evaluate the economics of treating fuels by using 13 different mechanical fuel treatments per plot. We are extending this analysis to explore the carbon dynamics associated with these fuel treatments and...

Urban forests are a critical element in sustainable urban areas because of the many environmental, economic, and social benefits that city trees provide. In order to increase canopy cover in urban areas, residential homeowners, who collectively own the majority of the land in most cities, need to engage in planting and retaining trees on their properties. This collaborative research project surveyed homeowners in Seattle, Washington, U.S., to examine their behaviors and attitudes toward the trees on their property. Attitudes toward trees were mapped to examine geographic distribution, as...

Processes that influence habitat selection in landscapes involve the interaction of habitat composition and configuration and are particularly important for species with complex life cycles. We assessed the relative influence of landscape spatial processes and local habitat characteristics on patterns in the distribution and abundance of spawning steelhead (Oncorhynchus mykiss), a threatened salmonid fish, across approximately 15,000 stream km in the John Day River basin, Oregon, USA. We used hurdle regression and a multi-model information theoretic approach to identify the relative...

Climate change in the 21st century will affect tree growth in the Pacific Northwest region of North America, although complex climate–growth relationships make it difficult to identify how radial growth will respond across different species distributions. We used a novel method to examine potential growth responses to climate change at a broad geographical scale with a focus on visual inspection of patterns and applications beyond sampled areas. We examined projected changes in climate within species distributions of mountain hemlock (Tsuga mertensiana), subalpine fir (Abies lasiocarpa),...

Many plant species have been introduced to the United States by humans since European settlement, sometimes deliberately and sometimes inadvertently, such as in contaminated crop seed or soil. Some species have successfully escaped cultivation and become invasive, spreading and establishing new populations distant from original population centers. Indeed, introduced plant species have forever changed the vegetative landscape of North America.

Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items. Current data and downloadable Excel files are available online.

Ethanol in sapwood was analyzed along vertical transects, through small spot cankers and larger basal cankers, of Phytophthora ramorum-infected stems of Quercus agrifolia at three sites in California. Trees with large basal cankers, known to attract scolytid beetles, had a 4.3 times higher ethanol level than trees with spot cankers that attract fewer beetles. We conclude that ethanol in P. ramorum cankers functions as a primary host attractant for scolytid beetles and is an important link in colonization of these cankers and accelerated mortality of Q. agrifolia. The results of this...