Treesearch

In the subalpine zone of the Rocky Mountains, climate change is predicted to result in an increase in the frequency and severity of spruce beetle outbreaks. Climate change itself may affect vegetation, potentially leading to changes in species composition. The direct and indirect effects of climate and disturbances on forest composition, biomass, and dynamics open the possibility for non-linear ecosystem responses. Modeling studies allow for the study of the interaction of these effects and their impact on the forest system. University of Virginia Forest Model Enhanced (UVAFME), an...

The mountain pine beetle (MPB) (Dendroctonus ponderosae) is one of the most prevalent disturbance agents in western conifer forests. It utilizes various species of pines (Pinus spp.) as host trees. Eruptive populations can cause extensive tree mortality. Since the late 1990s, extensive outbreaks have occurred from the southern Rockies to British Columbia. In Colorado, lodgepole pine (P. contorta) forests have been the most affected. Since 1996, about 3.4 million acres of lodgepole and ponderosa pine (P. ponderosa) forests have exhibited MPB-caused tree mortality. A large portion of the...

Understanding roundwood production in the United States at fine spatial and temporal scales is needed to support a range of analyses for decision making. Currently, estimates of county-level roundwood production are available at various time intervals for different regions of the country and for different products. Here we present our reasoning for moving to an annual timber products monitoring program and further present a comparison of sample designs to facilitate an annual program without increased effort. We found that both probability proportional to size and stratified simple random...

The forested watersheds of the Pacific Northwest can sequester a significant amount of atmospheric carbon dioxide (CO2), making them valuable carbon sinks for offsetting the carbon emissions that are contributing to global changes in the climate. However, as trees are storing carbon, water is leaching it from the soil. Some of the carbon is captured by microbial communities living in the stream’s hyporheic zone, a region within the streambed, where it is turned back into CO2. Gas exchanges between water and air release this CO2 back into the atmosphere. These carbon fluxes previously have...

Emerald ash borer (Agrilus planipennis) has killed millions of trees in the United States. Community managers face treatment or removal decisions for all publicly owned ash (Fraxinus spp.) trees. These decisions are based on the overall condition of each tree. In this study, the U.S. Forest Service-trained a Boy Scout troop in Oconomowoc, Wisconsin, U.S., in a tree health assessment protocol that used rubrics designed to measure physiological stress symptoms. The city provided tree inventory data, which included the location of 316 city-owned ash trees. After a two-hour training session,...

The demand for large-scale and long-term information on tree growth is increasing rapidly as environmental change research strives to quantify and forecast the impacts of continued warming on forest ecosystems. This demand, combined with the now quasi-global availability of tree-ring observations, has inspired researchers to compile large tree-ring networks to address continental or even global-scale research questions. However, these emergent spatial objectives contrast with paleo-oriented research ideas that have guided the development of many existing records. A series of challenges...

It is widely recognized that biotic interactions may act as important mediators of species responses to climate change. However, collecting the abiotic and biotic covariates at the resolution and extent needed to reveal these interactions from species distribution models is often prohibitively expensive and labor-intensive. Here we used crowd-sourced environmental DNA sampling - the inference of species presence from genetic material in the environment - and high-resolution habitat covariates across 630 sites over an area of nearly 10,000 km2 to build an accurate species distribution model...

The new eDNAtlas website and dynamic database allows land managers, scientists and the public to access results from environmental DNA (eDNA) collected from aquatic systems throughout the United States.

Social science offers rich descriptions of relationships between wildland-urban interface residents and wildfire, but syntheses across different contexts might gloss over important differences. We investigate the potential extent of such differences using data collected consistently in sixty-eight Colorado communities and hierarchical modeling. We find substantial variation across responses for all considered measures, much of which occurs at the community-level. Our results show that many aspects of relationships with wildfire meaningfully differ both within and across communities. Our...

Riparian vegetation along streams provides a suite of ecosystem services in rangelands and thus is the target of restoration when degraded by over-grazing, erosion, incision, or other disturbances. Assessments of restoration effectiveness depend on defensible monitoring data, which can be both expensive and difficult to collect. We present a method and case study to evaluate the effectiveness of restoration of riparian vegetation using a web-based cloud-computing and visualization tool (ClimateEngine.org) to access and process remote sensing and climate data. Restoration efforts on an...