• Fluoride in Thermal Spring Water and in Plants of Nevada and Its Relationship to Fluorosis in Animals

      Kubota, J.; Naphan, E. A.; Oberly, G. H. (Society for Range Management, 1982-03-01)
      Fluoride concentrations in water from selected thermal springs and in plants were determined to evaluate their role as sources of F- for grazing animals in Nevada. The F- concentration in water varied with thermal spring sources and ranged from about 2 to 17 ppm. F- concentration in plants ranged from about 0.1 to over 220 ppm, depending upon species of plants and the soil on which the plants were grown. The F- concentration in plants from any given thermal spring location was not uniformly high, but together with F- concentration of the water, appears to contribute to possible cases of fluorosis in cattle. Although small area-wise the spring waters and the area they flow over are important to grazing animals, because they provide drinking water and have lush forage.
    • Food Resource Partitioning by Sympatric Ungulates on Great Basin Rangeland

      Hanley, T. A.; Hanley, K. A. (Society for Range Management, 1982-03-01)
      The usefulness of a conceptual framework for understanding food selection by ungulates, based on four morphological parameters (body size, type of digestive system, rumino-reticular volume to body weight ratio, and mouth size), was tested by applying discriminant analysis to 194 monthly diet determinations based on microhistological fecal analysis for five sympatric species of ungulates in northeastern California and northwestern Nevada. In each season, the group means were located in the hypothesized order along the axis described by the first discriminant function: feral horse, domestic cow, domestic sheep, pronghorn, mule deer. Horse and cow diets consisted primarily of grasses. Pronghorn and mule deer diets consisted primarily of browse. Sheep diets were intermediate. Four browses (Artemisia spp., Cercocarpus ledifolius, Purshia tridentata, and Juniperus occidentalis) were selected as the most useful species for discriminating between animal species. The data and analyses support the hypothesized food selection framework.