Grasslands in the Pacific Northwest are characterized by seasonally wet, acidic soils that mainly support cool season grasses and a limited number of legume species. A major limitation to efficient animal production in grass-dominant pastures is the decline in the herbage growth rate and nutritional quality of forage from late...
Livestock grazing is the prominent land use in Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis [Beetle & A. Young] S.L. Welsh) steppe and has been present since the late 1800’s. There have been calls to remove livestock grazing from rangelands as historic grazing practices resulted in the degradation of some...
The sustainable use of natural resources, including the goods and services provided by pasturelands and rangelands, is of growing importance due to climatic uncertainty and population growth. Maintaining high productivity in livestock operations is necessary as land availability diminishes and global populations rise. The potential negative impacts to the environment...
The umbrella species concept is a single-species conservation strategy built on the notion that indirect protections are provided for multiple species that occupy the same area as a single, or umbrella, species. The utility of the umbrella species concept relies on similar associations of abundance, distribution, life history requirements, and...
Within the sagebrush steppe ecosystem, invasive annual grasses are of growing management concern as they outcompete native vegetation, change the fundamental nutrient cycling processes, decrease biodiversity, and increase frequency of wildfires. The most widely used and effective management tool to decrease invasive annual grass abundance, is the use of pre-emergent...
Arbuscular mycorrhizal fungi (AMF) are plant symbionts that associate with the vast majority of terrestrial plants species. The AMF colonizes the plant roots by penetrating the root cortical cells, where the fungi exchanges mineral nutrients with the host plant for photosynthates. This association exists as a complex system in which...
Greater sage-grouse (Centrocercus urophasianus: hereafter sage-grouse) abundance and distribution in North America has declined over the last century. Many factors have contributed to this decline, including habitat loss and fragmentation from human development with an associated potential for increased predation. While human development has been connected to lower sage-grouse demographic...
Wetland degradation has negative influences on wetland functions and services. The understanding of wetland functions requires the intersection of two science disciplines, ecohydrology and plant physiology for a correct approach on wetland restoration and management. Although studies assessing ecohydrological relationships to protect wetlands are relatively common, studies evaluating both ecohydrological...
Observed declines in native pollinator species worldwide has generated concern and focused research into the disturbances, past and present, which may have contributed to these losses. In grasslands, for example, habitat degradation and fragmentation from historical and current crop production and livestock grazing has left only a few remnants of...
In the area that is now Saguaro National Park East, grazing began in the 1880's. Because of the impact to the iconic saguaro cactus as well as all palatable plant species in the area, ecological damage in the park were determined to be so great that anti-grazing conservationists challenged the...