Treesearch

Physically dormant seeds of Munro's globemallow (Sphaeralcea munroana (Douglas) Spach [Malvaceae]) were scarified by boiling, tumbling, burning, dry-heating, and burning + heating treatments in an attempt to find an effective, operational, largescale treatment for nurseries and restoration activities. Results indicate that out of the tested treatments, seed germination was highest following boiling water scarification (49%). All other treatments did not achieve significant improvements in germination compared to the control. Findings should improve the use of this cool-season perennial for...

Five commercially produced seed lots of Wyoming big sagebrush (Artemisia tridentata Nutt. var. wyomingensis (Beetle & Young) S.L. Welsh [Asteraceae]) were stored under various conditions for 5 y. Purity, moisture content as measured by equilibrium relative humidity, and storage temperature were all important factors to successful seed storage. Our results indicate that no losses in germination will occur for at least 5 y if seeds are cleaned to 66 to 80% purity, dried to 30% equilibrium relative humidity, sealed in moisture-proof containers, and kept frozen at temperatures < 8 °C. Because...

Post-fire seeding of native species is intended to reduce weed entry, yet few studies have addressed the impacts of seeding methods on the establishment and persistence of exotic annuals. In summers of 2010 and 2011, we investigated productivity of exotic annuals across rehabilitation seedings that were established on the Scooby Wildfire site in northern Utah. The site, which was formerly dominated by Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young (Wyoming big sagebrush), burned in September 2008. Experimental treatments were applied in November 2008 and February 2009 to...

The Interagency Native Plant Materials Development Program outlined in the 2002 USDA and USDI Report to Congress, USDI Bureau of Land Management programs and policies, and the Great Basin Restoration Initiative encourage the use of native species for rangeland rehabilitation and restoration where feasible. The Great Basin Native Plant Selection and Increase Project was initiated to provide information that will be useful to managers when making decisions about selecting appropriate plant materials and technologies for restoration. The Program is supported by the USDI Bureau of Land...

The foothills north of Boise, Garden City, and Eagle make a beautiful backdrop for the urban areas below. This ecosystem provides city residents unparalleled recreational opportunities, serves as important wildlife habitat, provides clean water to residents, and supports the local economy. The foothills are also home to a wide variety of plants that have important ecological and economic roles. Native plants have naturally evolved with and adapted to the local foothills climate and soils. Nonnative plants are species that were introduced (accidentally or purposefully) to the foothills...

Land managers are routinely applying fuel reduction treatments to mitigate the risk of severe, stand-replacing fire in ponderosa pine communities of the southwestern US. When these treatments are burned by wildfire they generally reduce fire severity, but less is known about how they influence post-wildfire vegetation recovery, as compared to pre-fire untreated areas. We re-measured existing plots on the 2002 Rodeo-Chediski Fire 8 years after the wildfire to track plant community and exotic species response, as well as patterns of pine regeneration. We compared areas that experienced high-...

We used a multi-year data set from the 2002 Rodeo-Chediski Fire to detect post-fire trends in plant community response in burned ponderosa pine forests. Within the burn perimeter, we examined the effects of pre-fire fuels treatments on post-fire vegetation by comparing paired treated and untreated sites on the Apache-Sitgreaves National Forest.We sampled these paired sites in 2004, 2005 and 2011.

We used a physics-based model, HIGRAD/FIRETEC, to explore changes in within-stand wind behavior and fire propagation associated with three time periods in pinyon-juniper woodlands following a drought-induced bark beetle outbreak and subsequent tree mortality. Pinyon-juniper woodland fuel complexes are highly heterogeneous. Trees often are clumped, with sparse patches of herbaceous vegetation scattered between clumps. Extensive stands of dead pinyon trees intermixed with live junipers raised concerns about increased fire hazard, especially immediately after the trees died and dead needles...

Animals select habitat resources at multiple spatial scales. Thus, explicit attention to scale dependency in species-habitat relationships is critical to understand the habitat suitability patterns as perceived by organisms in complex landscapes. Identification of the scales at which particular environmental variables influence habitat selection may be as important as the selection of variables themselves. In this study, we combined bivariate scaling and Maximum entropy (Maxent) modeling to investigate multiscale habitat selection of endangered brown bear (Ursus arctos) populations in...

Spatial heterogeneity can constrain the movement of individuals and consequently genes across a landscape, influencing demographic and genetic processes. In this study, we linked information on landscape composition, movement behavior, and genetic differentiation to gain a mechanistic understanding of how spatial heterogeneity may influence movement and gene flow of bobcats in the agricultural landscape of Iowa (USA). We analyzed movement paths of 23 animals to parameterize landscape resistance surfaces, applied least cost path analysis to generate measures of effective geographic distance...