Treesearch

To better understand forest carbon (C) storage patterns, C budgets were constructed and contrasted among four stands of different vegetation, elevation, and disturbance histories from the northern Sierra Nevada of California, USA. The True-fir stand, considered to be undisturbed and at a higher elevation (1820 m), stored substantially more C than the three stands at lower elevation (1360–1430 m) and that had sustained various levels of disturbance. The Mixed Conifer stand was minimally disturbed by thinning 27 yr ago. The Oak stand was moderately disturbed by two fires in the past 17 yr....

Bark beetles are primary disturbance agents in western US forests. Outbreaks affect goods and services associated with forest ecosystems including timber, water, fish and wildlife habitats and populations, recreation opportunities, and many others. They can also affect wildfire behavior and its intensity. Assessments and evaluations of such impacts are important information to land managers, policy makers, and forest stakeholders, as well as to the broader public. Arriving at a complete and accurate assessment and evaluation is a complex process that necessarily considers effects and...

Coexistence of ecologically similar species can be maintained by partitioning along one or more niche axes. Three-dimensional structural complexity is central to facilitating resource partitioning between many forest species, but is underrepresented in field-based studies. We examined resource selection by sympatric northern spotted owls (Strix occidentalis caurina), a threatened species under the US Endangered Species Act, and nonnative barred owls (S. varia) in western Oregon, USA to explore the relative importance of canopy heterogeneity, vertical complexity of forest, and abiotic...

Effective conservation and management of small mammals require knowledge of the population dynamics of co-occurring species. We estimated the abundances, autocorrelations, and spatiotemporal associations of 4 small-mammal species from 2011–2016 using live-trapping mark-recapture methods on 9 sites across elevation and canopy openness gradients of a late-successional forest in the H. J. Andrews Experimental Forest, on the west slope of the Oregon Cascades. We also quantified species-specific spatial variation in adult sex ratios and body mass. We used Huggins closed capture models to...

I examined the implementation of a midstory herbicide treatment as the first phase in a two-phase shelterwood prescription in upland hardwood stands in Alabama, Tennessee, and Kentucky. The initial prescription for all three sites was similar: use herbicide to reduce the density of the midstory, allowing increased light to the established oak (Quercus spp.) reproduction. The goal was to increase understory light to at least 20 percent of full sun to promote oak seedling growth and recruitment over other species. Light was increased, but ephemeral and not to the 20-percent full sun goal....

This resource update is a brief look at some of the basic metrics that describe the status of and changes to forest resources in Tennessee. This information is based on field data collected using the USDA Forest Service Forest Inventory and Analysis (FIA) annualized sample design, and it is updated yearly.