PROJECTS
California Rancher Decision Making Survey
We collaborated with California Cattlemen's Association, California Farm Bureau Federation and UC Cooperative Extension to conduct a survey of over 500 California beef cattle ranchers who manage rangelands. California's rangelands provide for forage and livestock production, drinking and irrigation water, open space, and are one of the most biologically diverse ecosystems in the state and nation. >>More
Meadow Conditions on National Forest Grazing Allotments
The US Forest Service Region 5 Range Program initiated a region-wide, long-term meadow monitoring program to assess baseline meadow condition and trends in condition following the implementation of livestock use standards and guidelines for riparian areas. Our lab has teamed up with USFS Region 5 to begin analysis of this monitoring dataset. >>More
Water Quality on U.S. Forest Service Public Grazing Allotments
We developed a program that will evaluate water quality conditions, sources of water pollution, and guide management to improve water quality where needed in order to address concerns regarding nutrient and fecal indicator bacteria concentrations in U.S. Forest Service grazing allotments in the Sierra Nevada. >>More
Cattle Grazing, Mountain Meadows, and Yosemite Toad
We investigated factors determining temporal and spatial patterns of cattle grazing across Sierra Nevada mountain meadows to asses potential management risks/compatabilites for sensitive species such as the Yosemite toad. >>More
Forest and Grazing Management to Restore Aspen
Aspen are a keystone species, supporting significant diversity across the Sierra Nevada and southern Cascade landscape. Many stands are in decline due to altered fire regimes and grazing pressures. We are examining the unique niche aspen fill in this landscape, trends in stand condition, and the restoration of stand condition. >>More
Ecosystem Service-based State and Transition Models
California's oak-grassland ecosystems perform critical services, but current state and transition models (STMs) designed to guide ecosystem management are based solely on plant community structure. Within the context of woody species management, we are integrating ecosystem services into STM formulation to support management for multiple outcomes. >>More
Grazing and Prescribed Fire affects Water Quality at the Watershed Scale
Oak woodlands and chaparral provide many ecosystem services, including clean water. Grazing and fire are key management activities on these watersheds. We are conducting a long-term evaluation of water quality response to livestock grazing intensity and prescribed fire on 11 oak woodland and chaparral catchments. >>More
Restoration and Grazing Management on Mountain Meadows and Streams
Ecological concerns about livestock grazing include impacts on riparian vegetation, stream channel stability, and aquatic species. We surveyed over 100 rangeland streams and riparian areas, so we could identify grazing management tools to enhance aquatic habitat, hydrologic function, and biological integrity. >>More
What is the Quality of Water in Rangeland Streams?
Rangeland streams provide water for drinking, irrigation, and recreation. We conducted a water quality survey of streams across California’s major rangeland vegetation, geologic, and climatic zones. >>More
Vegetation and Wetlands Filter Pollutants in Runoff
The management of vegetation to trap waterborne pollutants is referred to as a vegetative “buffer” or “filter” strip. Small wetlands can also serve this function. We have conducted numerous studies to evaluate how well buffers and wetlands filter pathogens, nutrients, and sediments from pasture runoff. >>More
Are Microbial Water Quality Indicators Really Sentinels of Safe Water?
Surface water contamination with pathogens is a major human health concern. Pathogens of concern include Cryptosporidium parvum, Giardia, Salmonella, and E. coli O157:H7. Water quality standards focus on indicators such as fecal coliform. Our results from surveys of major grazing watersheds in the Sierra Nevada cast doubt on the utility of indicator bacteria. >>More
Many Factors Work Together to Determine Stream Water Temperature Dynamics
Maintaining cool water is important in many rangeland streams to support cold water fishes. To advise range managers on how to reduce stream temperatures, we examined stream and air temperatures, shade from riparian vegetation, streamflow, and topography on several rangeland watersheds. >>More
Irrigated Pasture and Meadow Management to Improve Water Quality
Recent regulatory developments have brought increasing focus on the quality of water discharged from irrigated pastures and meadows in California. We conducted a survey of irrigated pasture systems to identify management to reduce pollutants in runoff, and evaluate associated impacts on livestock production. >>More