Treesearch

This guidebook describes major biological and physical attributes of the 119-ha (293-ac) Mohawk Research Natural Area. The area supports old-growth Douglas-fir (Pseudotsuga menziesii) forest characterized by plant associations representative of the western Cascade foothills. These include the western hemlock/Oregon grape-salal (Tsuga heterophylla/Berberis nervosa-Gaultheria shallon); western hemlock/Oregon grape/swordfern (Tsuga heterophylla/Berberis nervosa/Polystichum munitum); and western hemlock/Oregon oxalis (Tsuga heterophylla/Oxalis oregana) forest plant associations.

This paper deals with 3D numerical simulations of two fires fronts (head and backfire) propagating simultaneously through a grassland fuel. The simulations were carried out using a “fully” physical and three-dimensional fire model (namely WFDS). One of the objectives of this work, was to evaluate the potential for fully physical fire model to simulate the interactions between two fire fronts (a head fire and a backfire), in conditions similar to those encountered during suppression fire operations. A set of numerical simulations was first carried out for standalone head fires propagating...

Research Benefits Society. Forest Service research helps society make choices about water, wildlife, and natural resources. Scientific understanding gained from research transforms the way land managers rise to challenges. For example, the tools and information used daily by managers and policymakers to make cost-effective and environmentally sound fire management decisions are based on research about fire behavior, fire ecology, fuels, and smoke in ecosystems. As a result, citizens are provided ways to secure their homes from fire, are warned when smoke requires them to take precautions,...

Provision of forage for wild and domestic ungulates, and the associated impacts of their herbivory, are contentious issues for wildland management in western North America. We quantified the composition, above-ground net production (ANP), and utilization of herbaceous and shrub vegetation in five non-forest and seven forest cover types across the core springsummer- fall range of the Yakima elk herd in the eastern Washington Cascade Range. We randomly sampled each cover type along three elevational transects during a two-year period. Riparian/meadow was the most productive cover type (2,752...

Wildfire links social and ecological systems in dry-forest landscapes of the United States. The management of these landscapes, however, is bifurcated by two institutional cultures that have different sets of beliefs about wildfire, motivations for managing wildfire risk, and approaches to administering policy. Fire protection, preparedness, and response agencies often view wildfire as a threat to be mitigated or extinguished to protect things that humans value (e.g., houses, and timber), whereas land management agencies and conservation organizations often view wildfire as an essential...

Land managers in the western US are beginning to understand that early 20th century forests displayed complex patterns of composition and structure at several different spatial scales, that there was interplay between patterns and processes within and across scales, and that these conditions have been radically altered by management. Further, they know that restoring integrity (see Definition of Terms) of these conditions has broad implications for the future sustainability (see Definition of Terms) of native species, ecosystem services, and ecological processes. Many are looking for...

We present results of a spatially explicit, individual-based stochastic dispersal model (HexSim) to evaluate effects of size and spacing of patches of habitat of Northern Spotted Owls (NSO; Strix occidentalis caurina) in Pacific Northwest, USA, to help advise recovery planning efforts. We modeled 31 artificial landscape scenarios representing combinations of NSO habitat cluster size (range 4–49 NSO pairs per cluster) and edge-to-edge cluster spacing (range 7–101 km), and an all-habitat landscape. We ran scenarios using empirical estimates of NSO dispersal dynamics and distances and stage...

Resource selection functions (RSFs) are typically estimated by comparing covariates at a discrete set of “used” locations to those from an “available” set of locations. This RSF approach treats the response as binary and does not account for intensity of use among habitat units where locations were recorded. Advances in global positioning system (GPS) technology allow animal location data to be collected at fine spatiotemporal scales and have increased the size and correlation of data used in RSF analyses. We suggest that a more contemporary approach to analyzing such data is to model...

The principle of energy allocation states that individuals should attempt to maximize fitness by allocating resources optimally among growth, maintenance, and reproduction. Such allocation may result in trade-offs between survival and reproduction, or between current and future reproduction. We used a marked population of North American elk (Cervus elaphus) to determine how energetic costs of reproduction in the current year affect survival and reproduction in the subsequent year. Using a multistate mark-recapture model we examined the influence of individual and environmental variation on...

Public land management agencies have incorporated the concept of vulnerability into protocols for assessing and planning for climate change impacts on public forests and grasslands. However, resource managers and planners have little guidance for how to address the social aspects of vulnerability in these assessments and plans. Failure to assess social vulnerability to climate change during management planning could compromise land management agencies’ adaptation strategies as well as public support for these strategies. We provide a framework for understanding and assessing social...