Treesearch

The Sky Islands of southeastern Arizona, which consist of separate mountain ranges within a desert matrix, are a unique biodiversity hotspot hosting many neotropical bird species that cannot be seen anywhere else in the United States. Residents of this region depend on ecotourism for their livelihood and there is an above-average concentration of citizens skilled at identifying birds by sight and sound. After the Horseshoe Two wildfire in 2011 burned a large portion of the Chiricahua range, the local residents approached RMRS with concerns about effects on the bird populations. RMRS...

Cogongrass (Imperata cylindrica (L.) Beauv.) is a Southeast Asian warm-season perennial grass species that has spread to all continents except Antarctica. It is considered among the worst problematic weeds on a global scale. Control of cogongrass is difficult, especially in forests. This 6-page fact sheet written by Patrick J. Minogue, Brent V. Brodbeck, and James H. Miller and published by the UF/IFAS School of Forest Resources and Conservation presents recommendations for control strategies that will work in mixed pine-hardwood forests and pine forests. http://edis.ifas.ufl.edu/fr411

Over the last decade, considerable progress has been made in developing vulnerability assessment tools and in applying these methodologies to identify and implement climate change adaptation approaches for forest ecosystems and forest management organizations in Canada and the United States. However, given that adaptation processes are in early stages, evaluation of approaches across agency, organizational, and geographic boundaries is critical. Thus, we conducted a qualitative comparison of three conceptual frameworks for climate change vulnerability assessment and adaptation efforts in...

Tripyrrole molecules have received renewed attention due to reports of numerous biological activities, including antifungal, antibacterial, antiprotozoal, antimalarial, immunosuppressive, and anticancer activities. In a screen of bacterial strains with known toxicities to termites, a red pigment-producing strain, HDZK-BYSB107, was isolated from Chamaecyparis lawsoniana, which grows in Oregon, USA. Strain HDZK-BYSB107 was identified as Serratia marcescens subsp. lawsoniana. The red pigment was identified as prodigiosin using ultraviolet absorption, LC-MS, and 1H-NMR spectroscopy. The...

Wind is a common canopy disturbance in the upland oak (Quercus)- and hickory (Carya)- dominated stands of the Central Hardwood Region of the eastern US. Canopy openings range from small gaps, resulting from windthrow of single dominant trees, to occasional large gaps of many hectares formed by straight-line winds associated with severe thunderstorms and rare subtropical hurricanes. Vegetation regeneration response in small gaps and larger artificially created (i.e., timber harvested) gaps has been extensively studied, but little has been reported on naturally formed large gaps (> 6 trees)...

Phenological synchrony can promote population growth in species with positive density dependence. Variation among life stages in the thermal thresholds for development can foster phenological synchrony under thermal regimes that include frequent occurrence of temperatures between developmental thresholds. The southern pine beetle is an insect with positive density dependence that has recently undergone important shifts in population abundance at the northern extremes of their distribution. We evaluated the hypothesis that cooler winter temperatures in their northern range cause a convergenc...

Urban greenways are increasingly seen as sustainable infrastructure initiatives designed to catalyze economic development, urban renewal and healthy cities. However, there has been little consideration for how the racial and socioeconomic composition of neighborhoods influence resident support for greenways. This is important due to documented divergent racial preferences for recreation and the potential paradoxical impact greenways can have on gentrification. Hence, this study assessed resident perceptions of the Atlanta BeltLine in two neighborhoods differing in their racial and socioecon...

Forested watersheds provide important ecosystem services through the provision of high quality freshwater, mitigation of floods, and maintenance of base flows. How alteration of these services under ongoing climate change is mediated by vegetation dynamics is not fully understood. Combining independent remote sensing based vegetation information and distributed hydrological modeling, we investigated the impact of climate-induced vegetation dynamics on long-term non-stationary hydrologic behavior in two forested watersheds in the southern Appalachians. We found significant increases in...

Modeling and simulating tree spatial distribution in complex forests is important to ecologists and applied scientists who seek to both understand pattern-creating biological processes and create realistic model forests that can be used for hypothesis testing and sampling experiments. Several patterns of tree spatial distribution can co-occur in a forest. Clustering can occur due to localized patterns of growth and mortality of larger trees and corresponding regeneration of smaller trees, while trees of medium size can exhibit more uniform patterns. Inter-tree interaction may be characteriz...