Treesearch

Limestone hawksbeard is a western species occurring in southern British Columbia, Alberta, Saskatchewan, and south to northern New Mexico, Arizona, and central California (Bogler 2006; USDA NRCS 2019). It occurs primarily east of the Cascade Mountains in the Pacific Northwest (Hitchcock and Cronquist 2018). Populations are most abundant in northern California and southern Oregon, becoming local and infrequent eastward (Babcock and Stebbins 1938).

Diversity of applications, productivity potential, broad suitability and genetic variations make Populus a valuable fast-growing genus. Our goal was to assess if clonal site-suitability varies with rotation-length. We examined survival, growth (height, diameter at breast height) and estimated stem and total-wood (stem and branches) biomass of 89 clones near Fountain, North Carolina (35°42′7.52″ N, 77°34′35.04″ W) in the coastal southeastern USA at four- and eight-year rotations. The unsuitability of some clones was evident at early age while other clones became less suitable with stand...

Forest Service employees have access to all features of this and other species descriptions through the Birds of the World database. Access Birds of the World through the National Forest Service Library database collection. Recent analysis of mitochondrial genes suggests that the predominantly brown towhees - California, Abert's, Canyon, and White-throated - are more closely related to the Melozone ground-sparrows than they are to the predominantly black or green towhees. As a result, “brown towhees” are now placed in the genus Melozone. See the 51st Supplement to the AOU Checklist of...

With projected increasing intensity of hurricanes and large uncertainty in the path of forest recovery from hurricanes, studies are needed to understand the fundamental response of forests to canopy opening and debris deposition: the response of the abiotic factors underneath the canopy. Through two manipulative experiments and instrumenting prior to Hurricane Maria (2017) in the Luquillo Experimental Forest (LEF) of Puerto Rico, this study found a long recovery time of primary abiotic factors (beneath canopy light, throughfall, and temperature) influenced by the disturbance of canopy...

Smoke emissions from wildland fires contribute to concentrations of atmospheric particulate matter and greenhouse gases, influencing public health and climate. Prediction of emissions is critical for smoke management to mitigate the effects on visibility and air quality. Models that predict emissions require estimates of the amount of combustible biomass. When measurements are unavailable, fuel maps may be used to define the inputs for models. Mapped products are based on averages that poorly represent the inherent variability of wildland fuels, but that variability is an important source...

We describe a polar coordinate transformation of vegetation index profiles which permits a broad-scale comparison of location-specific phenological variability influenced by climate, topography, land use, and other factors. We apply statistical data reduction techniques to identify fundamental dimensions of phenological variability and to classify phenological types with intuitive ecological interpretation. Remote sensing-based land surface phenology can reveal ecologically meaningful vegetational diversity and dynamics across broad landscapes. Land surface phenology is inherently complex...

Species of biscuitroot (Lomatium: Apiaceae) are endemic to western North America, where multiple species can be common members of perennial wildflower communities from basin sagebrush-steppe and juniper woodlands up to alpine meadows. Despite Lomatium being the largest genus of Apiaceae in North America, little is known about its pollination needs or pollinators. Manual pollinations of the tiny flowers of one species, desert parsley (L. dissectum), showed it to be a self-compatible species, akin to other genera of Apiaceae. Seed production, however, largely requires pollinators to move...

The statistical analysis of wildland fire activity is integral to wildland fire planning, operations, and research across the globe. Historical fire records are inputs to fire danger rating applications, fire-potential forecast models, geospatial fire modeling systems, and other tools for risk assessment, planning, budgeting, and decision support at multiple scales (Manzello et al. 2018). Spatiotemporal analyses of wildfire activity are used to characterize patterns and trends in relation to potential drivers such as population, land use, climate, and fire-control policies and to understand...

This paper describes a new dataset mined from the public archive (1999–2014) of the U.S. National Incident Management System/Incident Command System Incident Status Summary Form (a total of 124,411 reports for 25,083 incidents, including 24,608 wildfires). This system captures detailed information on incident management costs, personnel, hazard characteristics, values at risk, fatalities, and structural damage. Most (98.5%) of the reports are fire-related, followed in decreasing order by other, hurricane, hazardous materials, flood, tornado, search and rescue, civil unrest, and winter...

Emerald ash borer (EAB), a wood‐boring insect native to Asia, was discovered near Detroit in 2002 and has spread and killed millions of ash trees throughout the eastern United States and Canada. EAB causes severe damage in urban areas where it kills highvalue ash trees that shade streets, homes, and parks and costs homeowners and local governments millions of dollars for treatment, removal, and replacement of infested trees. We present a multistage, stochastic, mixed‐integer programming model to help decision‐makers maximize the public benefits of preserving healthy ash trees in an urban...