Treesearch

Municipal water managers need to know if water will be reliably available from watersheds. Civil engineers need to calculate stream discharge to construct bridges to withstand 100-year floods. A hypothesis proposed in 1997 by Gordon Grant, a research hydrologist with the USDA Forest Service Pacific Northwest Research Station, underlies a method for getting this information from rivers without gauge networks or long-term flow data. Since then, laboratory experiments and field measurements have validated the hypothesis to the degree that it may now be considered a theory.Critical flow is a...

Scotch broom [Cytisus scoparius (L.) Link] is a large nonnative, leguminous shrub that threatens native plant communities by rapidly invading recently disturbed sites, competing vigorously for soil water and nutrients, and imparting soil legacy effects that inhibit native plants. In the Pacific Northwest, logging debris retention after forest harvesting prevents or slows C. scoparius invasions. A series of studies were conducted to determine potential mechanisms by which logging debris modifies the light environment to limit germination and growth of C. scoparius. In laboratory studies,...

Softwood logs comprise a large portion of forest product exports from the United States. Most of these exports have occurred between the Pacific Northwest region of the United States and several Asian countries. In this study, the extent and degree of market integration of softwood log exports from 1996 to 2018 are examined by co-integration analyses and permanent–transitory decomposition. Softwood log exports to Japan and South Korea appear to be in the same economic market and show a high degree of integration, while trade between the United States and China has evolved more independently...

We demonstrate a generalizable approach for assessing climate change effects on tribally important ecosystem goods and services. Indigenous peoples may be highly vulnerable to the impacts of climate change because they rely on ecosystem goods and services, such as traditional foods, hunting, timber production, nontimber forest resources, and cultural resources. However, there are few assessments that have examined the potential impact of climate change on these goods and services and even less that examine ecological, socio-economic, and cultural resources in the Pacific Northwest, USA....

U.S. federal government agencies play an important role in mitigating some risks posed to communities by natural hazard events, especially communities with high proportions of low-income or minority residents. Ongoing efforts of the U.S. Forest Service (USFS) to reduce the buildup of forest fuels on national forests, particularly in dry mixed-conifer forests of the U.S. West, are an example. Federal land management agencies must comply with the Executive Order on Environmental Justice (EJ Order, 59 Fed. Reg 7629, 1994), but there is scant documentation of whether these agencies have...

In Southern California, the Santa Ana winds are famous for their role in spreading large wildfires during the fall/winter season. Combined with Southern California's complex topography, Santa Anas create challenges for modeling wind-fire relationships in this region. Here, we assess heterogeneity of winds during Santa Ana and non-Santa Ana days, on days with and without large-fire ignitions, across a modern high-density observational network of 30 meteorological stations. Wind speeds on Santa Ana days with a large fire ignition (mean windspeed = 5.19 m/s) are significantly higher than on...

Following a wildfire, regeneration to forest can take decades to centuries and is no longer assured in many western U.S. environments given escalating wildfire severity and warming trends. After large fire years, managers prioritize where to allocate scarce planting resources, often with limited information on the factors that drive successful forest establishment. Where occurring, long-term effects of postfire salvage operations can increase uncertainty of establishment. Here, we collected field data on postfire regeneration patterns within 13- to 28-yr-old burned patches in eastern...

Modeling landscape use (i.e., estimating the probability or relative probability of use, occurrence, or selection in a given area and time) by ungulates is an increasingly common and important practice in research and management. Models of occupancy, distribution, movement, habitat use, and resource selection are formal approaches by which landscape use has been characterized and results published for a myriad of ungulate species. Understanding landscape use has benefited from a growing volume of data on animal locations and model covariates, and the ease of modeling with automated...

The National Visitor Use Monitoring (NVUM) program data underlies estimates of the volume of recreation use of the National Forest System. The data also enable estimation of both the local economic contributions and nonmarket benefits of that visitation. Applications include evaluating the effects of natural disasters, site characteristics, and climate change, as well as expenditure and benefit transfers. This article describes the history and science background of the NVUM program, outlines the methods used in estimating market and nonmarket economic outcomes, and lists some examples of...

There is limited research on recreationists’ responses to changes in resource conditions after wildfire. Existing studies often rely on presenting visitors with hypothetical wildfire scenarios or simulated changes in conditions. We completed a quick assessment of recreation visitation and visitor experience in the months immediately following an actual high-severity wildfire within a popular river canyon in Oregon, USA. We also explored the influence of wildfire on the recreation plans of campers. We found that recreation use dropped sharply in the immediate aftermath of the wildfire, but...