Treesearch

Forests are an incredibly important resource across the globe, yet they are threatened by climate change through stressors such as drought, insect outbreaks, and wildfire. Trailing edge forests - those areas expected to experience range contractions under a changing climate - are of particular concern because of the potential for abrupt conversion to non-forest. However, due to plant-climate disequilibrium, broad-scale forest die-off and range contraction in trailing edge forests are unlikely to occur over short timeframes (<~25-50 yr) without a disturbance catalyst (e.g., wildfire). This...

This proactive conservation strategy addresses the unique situation of limber pine in the Greater Rocky Mountain National Park Area (GRMNPA). The target area includes Rocky Mountain National Park and surrounding areas of northern Colorado and southern Wyoming. The GRMNPA is at the infection front for white pine blister rust (WPBR) where populations were also impacted by the recent mountain pine beetle epidemic and are threatened by climate change. This is the first proactive conservation strategy for a five-needle pine species in North America. It focuses on timing specific monitoring...

Recent, widespread spruce beetle (Dendroctonus rufipennis) outbreaks have driven extensive tree mortality across western North America. Post-disturbance forest management often includes salvage logging to capture economic value of dead timber, reduce fire hazard, and meet other social or ecological objectives. Little is known about effects of salvage logging on surface fuel loads or plant understory communities in Engelmann spruce (Picea engelmannii)-dominated forests. We sampled fine and coarse woody debris, ground cover, and plant species composition along transects in spruce-beetle...

Molecular tools are commonly directed at refining taxonomies and the species that constitute their fundamental units. This has been especially insightful for groups for which species hypotheses are ambiguous and have largely been based on morphological differences between certain life stages or sexes, and has added importance when taxa are a focus of conservation efforts. Here, we examine the taxonomic status of Arsapnia arapahoe, a winter stonefly in the family Capniidae that is a species of conservation concern because of its limited abundance and restricted range in northern Colorado,...

The extent of the Earth's surface burned annually by fires is affected by a number of drivers, including but not limited to climate. Other important drivers include the amount and type of vegetation (fuel) available and human impacts, including fire suppression, ignition, and conversion of burnable land to crops. Prior to the evolution of hominids, area burned was dictated by climate via direct influences on vegetation, aridity, and lightning. In the future, warming will be accompanied by changes in distribution, frequency, intensity, and timing of precipitation that may promote or...

How did the forest and community get to the point where they were willing to take on managing a fire of this size and duration for resource benefit and hazard reduction? Science has recognized for decades that many forested ecosystems of the American West are shifting away from historically fire-adapted conditions. Beginning in the 1970’s a small handful of managers recognized this issue and developed wildland fire use concepts. However, in the current era of increasing encroachment of human development, climate change, and accumulated fuels, uncertain outcomes have emphasized the default...

Mesocarnivores, fisher, marten, lynx, wolverine and others, are an important part of forest ecosystems, but they are often difficult to detect, occur in low densities, and have large home ranges. This makes it difficult for biologists to estimate the number of individuals in a specific species in a particular ecosystem.Publication: RMRS-GTR-388

Species at risk of extinction are not uniformly distributed in space. Concentrations of threatened species may occur where threatening processes are intense, in refuges from those processes, or in areas of high species diversity. However, there have been few attempts to identify the processes that explain the distribution of at-risk species. Here, we identified the relative importance of biological traits, environmental factors, and anthropogenic stressors in driving the spatial patterns of both total and at-risk species richness of North American mammals and birds. Environmental factors...

Dry mixed-conifer forests are widespread in the interior Pacific Northwest, but their historical fire regimes are poorly characterized, in particular the relative mix of low- and high-severity fire. We reconstructed a multi-century history of fire from tree rings in dry mixed-conifer forests in central Oregon. These forests are dominated by ponderosa pine (Pinus ponderosa Lawson & C. Lawson), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and grand fir (Abies grandis (Douglas ex D. Don) Lindl.). Across four, 30-plot grids of ~800 ha covering a mosaic of dry mixed-conifer forest types,...

Biological soil crusts (BSCs) exist commonly on soil surfaces in many arid and semiarid areas, and disturbed soil surfaces in more mesic environments. BSCs perform many essential ecological functions. Substantial resources have been invested trying to restore or replace BSCs that have been damaged by anthropogenic disturbances, with various levels of success. The nexus of sciences related to BSC establishment and restoration, and to aerobiology suggests that crusts are established and reestablished naturally via commonly occurring ecological processes. Formation of BSCs can be accelerated...