A5084979383- Rangeland and Wildlife Management
- Ecology and Vegetation Dynamics Studies
- Fire effects on ecosystems
- Ruminant Nutrition and Digestive Physiology
- Soil Carbon and Nitrogen Dynamics
- Turfgrass Adaptation and Management
- Plant Water Relations and Carbon Dynamics
- Rangeland Management and Livestock Ecology
- Pasture and Agricultural Systems
- Species Distribution and Climate Change
- Plant and animal studies
- Botany, Ecology, and Taxonomy Studies
- Forest Management and Policy
- Wildlife Ecology and Conservation
- Seedling growth and survival studies
- Plant Parasitism and Resistance
- Forest ecology and management
- Mycorrhizal Fungi and Plant Interactions
- Plant and fungal interactions
- Soil and Unsaturated Flow
- Aeolian processes and effects
- Genetic and phenotypic traits in livestock
- Peatlands and Wetlands Ecology
- Soil and Water Nutrient Dynamics
- Agroforestry and silvopastoral systems
Fort Keogh Livestock and Range Research Laboratory
2016-2025
Agricultural Research Service
2016-2025
United States Department of Agriculture
2007-2024
John Wiley & Sons (United States)
2020
Ecological Society of America
2020
Miles College
2004-2010
Texas Tech University
2000-2005
Northern Plains Agricultural Research Laboratory
2004
University of Nebraska–Lincoln
2004
Woodward (United States)
2002-2004
ABSTRACT Selective grazing of burned patches can be intense if animal distribution is not controlled and may compound the independent effects fire on soil characteristics. Our objectives were to quantify patch burning wind erosion, water content, temperature in sand sagebrush ( Artemisia filifolia Torr.) mixed prairie. We selected 24, 4‐ha plots near Woodward, OK. Four during autumn (mid‐November) four spring (mid‐April), served as nonburned controls for each two years. Cattle given...
Current management paradigms suggest deferring grazing rangeland for two years post-fire to avoid additional stress on native grass species, but there is little research supporting these recommendations. This study was conducted within and adjacent the burn area of a wildfire evaluate differences in diet quality, botanical composition, foraging behavior beef cattle burned unburned spring fall year following fire. Diet composition masticate samples were collected during 20 min bite-count...
Theory predicts that strong indirect effects of environmental change will impact communities when niche differences between competitors are small and variation in the direct experienced by is large, but empirical tests lacking. Here we estimate negative frequency dependence, a proxy for differences, quantify climate on each species. Consistent with theory, four five strongest species showing weak dependence. Indirect also stronger where there greater effects. Overall responses to...
Abstract Models of plant–plant interactions underpin our understanding species coexistence, invasive plant impacts, and community responses to climate change. In recent studies, models competitive failed predictive tests, thereby casting doubt on results many past studies. We believe these model failures owe at least partly heterogeneity in unmodeled factors (e.g., nutrients, soil pathogens) that affect both target plants neighboring competitors. Such is ubiquitous, do not account for it...
For nearly a century, invasive annual grasses have increasingly impacted terrestrial ecosystems across the western United States. Weather variability associated with climate change and increased atmospheric carbon dioxide (CO<sub>2</sub>) are making even more difficult challenges of managing grasses. As part special issue on impacts soil water conservation, topic is being addressed by scientists at USDA Agricultural Research Service to emphasize need for additional research future studies...
Nondestructive standing crop estimators are important for efficient monitoring of native and agronomic systems. This study evaluated plot pasture estimates using LAI‐2000, visual obstruction, canopy height, weighted plate measurements. Research was conducted in Lubbock County, Texas, 1999 on areas dominated by Amarillo fine sandy loam (fine‐loamy, mixed, thermic Aridic Paleustalfs). Five hundred estimation samples were collected each method along 25 transects, transect mean used the trials....
Restoration of historic fire regimes is complicated by concerns about exotic plant invasions, yet little known how the two may interact. Seeds Japanese brome, spotted knapweed, Russian and leafy spurge were subjected to at six fuel loads (100 700 g m −2 ) a nonburned control. Fires simulated with field-cured grass time–temperature profiles developed from thermocouples soil surface. Emergence was determined species load in growth chambers. Fuel explained 98% variation mean heat dosage...
Abstract Questions What factors explain the variation in plant survival parameters across species and ecosystems? Location W estern N orth A merica. Methods We compiled six long‐term data sets from western merica to test for ecosystem‐dependent demographic responses forbs grasses. Based on these data, we characterized 123 survivorship curves 109 species. Three were extracted curves: rate at age 1, life expectancy a parameter describing shape of curve. used mixed effects model compare...
In perennial grassland dominated systems, belowground bud banks regulate plant community dynamics. Plant responses to disturbance are largely driven by the ability generate future aboveground growth originating from axillary buds. This study examined bank dynamics for Bouteloua gracilis, Hesperostipa comata, and Pascopyrum smithii following fire in northwestern mixed-grass prairie eastern Montana, USA. Belowground buds were counted classified three growing seasons determine immediate...
As public and scientific interest in black-tailed prairie dogs has grown, views about their ecological role have become polarized. We evaluated three claims frequently made concerning the status of interactions with other species: (1) that historically occupied 40 million to 100 hectares (ha) now occupy only 1 2 percent former range, (2) large ungulates preferentially forage on dog colonies, (3) do not reduce carrying capacity for herbivores. The conclusion up ha is supported by literature,...
We evaluated the visual obstruction method as a non-destructive means of estimating herbage standing crop in tallgrass prairie.Prediction models were developed for both plot-level and pasture-level estimates by regressing from clipped plots on measurements (VOM) 48, 20sample trials.Trials conducted year-round burned non-burned sites different seral stages with various levels productivity grazing pressure.Separate required pastures, but applied across all other variables unaffected community...
Abstract Auxinic herbicides, such as 2,4-D and dicamba, that act plant growth regulators are commonly used for broadleaf weed control in cereal crops (e.g., wheat, barley), grasslands, noncroplands. If applied at late stages, while cereals developing reproductive parts, the herbicides can reduce seed production. We tested whether have this same effect on invasive annual grass Japanese brome. The 2,4-D, picloram were typical field use rates to brome various stages a greenhouse. Picloram...