Treesearch

There is a widely expressed need to improve upon the legacy pyrolysis and combustion properties of forest litter and live foliage developed two to three decades ago (e.g., Burgan and Susott 1991; Rothermel 1972; Sussott 1980, 1982; Shafizadeh et al. 1975, 1977) to adapt to the physical fire models (i.e., Fire Dynamic Simulator [FDS]), as well as accommodate the unusual properties of live and dead vegetation involved in wildfires that suggest improving the fire physics itself. Although the Forest Products Laboratory (FPL) in the Forest Service, Department of Agriculture has been developing...

An unprecedented conservation effort is underway across 11 western states to address risks to sagebrush ecosystems and the species that depend on them. The sagebrush biome - the largest biome in the Lower 48 states - provides a large diversity of habitats and supports more than 350 species of conservation concern. Since Euro-American settlement in the mid-1800s, this “sagebrush sea” has been reduced in area by nearly half and many of the remaining sagebrush ecosystems have been significantly altered.

Adaptive seed dispersal mechanisms are fundamental to plant fitness, but dispersal advantage is scale-dependent. We tested the hypothesis that informed dispersal in response to an environmental cue enables dispersal by wind on a local scale for Astragalus holmgreniorum, a desert species restricted to swales and wash skirts with overland flow, but prevents longer-distance dispersal by water into unfavorable wash habitats.

Ecological resilience is essential for maintaining ecosystem services in an era of rapid global change, but successful attempts to operationalize it for managing ecosystems at risk have been limited. Clear formulation and application of ecological resilience concepts can guide ecosystem management so that it enhances the capacity of ecosystems to resist and recover from disturbances and provides adaptive space for periods of ecological reorganization. As originally defined, ecological resilience measures the amount of perturbation required to change an ecosystem from one set of processes...

Canada lynx (Lynx canadensis) occupy cold wet forests (boreal and subalpine forest) that were structured by natural disturbance processes for millennia. In the Southern Rocky Mountains, at the species’ southern range periphery, Canada lynx habitat has been recently impacted by large-scale disturbance from spruce beetles (Dendroctonus rufipennis). This disturbance poses a challenge for forest managers who must administer this novel landscape in ways that also facilitate timber salvage. To aid managers with this problem, we instrumented Canada lynx with GPS collars to document their selection...

Roads have several negative effects on large mammals including restricting movements, isolating populations, and mortality due to vehicle collisions. Where large mammals regularly cross roads, driver safety is also a concern. Wildlife road crossing structures are often proposed to mitigate the negative effects on wildlife and human safety. However, few studies have compared the efficacy of different methods in identifying wildlife road crossing and mitigation locations.

Connectivity and wildlife corridors are often key components to successful conservation and management plans. Connectivity for wildlife is typically modeled in a static environment that reflects a single snapshot in time. However, it has been shown that, when compared with dynamic connectivity models, static models can underestimate connectivity and mask important population processes. Therefore, including dynamism in connectivity models is important if the goal is to predict functional connectivity. We incorporated four levels of dynamism (individual, daily, seasonal, and interannual)...

The mountain pine beetle (MPB), Dendroctonus ponderosae, is an eruptive endemic forest pest that is undergoing substantial range expansion in response to recent climatic changes, breaching geographic barriers, exploiting novel hosts, and affecting millions of hectares of conifer forests in western North America. Current management approaches have been unable to keep pace with MPB population outbreaks, and novel and aggressive management responses are required as MPB’s range expansion progresses. Gene silencing through RNA interference (RNAi) is an emerging pest management approach that is...

Salvage logging in burned forests can negatively affect habitat for white-headed woodpeckers (Dryobates albolarvatus), a species of conservation concern, but also meets socioeconomic demands for timber and human safety. Habitat suitability index (HSI) models can inform forest management activities to help meet habitat conservation objectives. Informing post-fire forest management, however, involves model application at new locations as wildfires occur, requiring evaluation of predictive performance across locations. We developed HSI models for white-headed woodpeckers using nest sites from...

Regional-scale mountain pine beetle (Dendroctonus ponderosae) outbreaks in the first decade of the 2000s affected millions of hectares of lodgepole pine (Pinus contorta) in western North American forests. In Colorado, 1.4 million ha exhibited high mortality. These events prompted questions about whether historical outbreaks reached the scale of this most recent event. We aimed to reconstruct past mortality events in lodgepole pine forests in the northern Colorado Front Range and to determine whether these were of similar extent to the 2000s outbreak. We identified logs of mountain pine...