• Change in Bacterial Populations Downstream in a Wyoming Mountain Drainage Basin

      Skinner, Q. D.; Adams, J. C.; Beetle, A. A.; Roehrkasse, G. P. (Society for Range Management, 1984-05-01)
      Ten bacteriological tests were utilized to monitor different bacterial populations found in water samples taken from streams draining high mountain rangeland. Livestock grazing and recreation constituted the major uses of the study area. Vegetation types were typical of those found in other sub-alpine and alpine zones in the central Rocky Mountains. Results show differences in counts of bacteria between sampling sites along individual streams sampled with the exception of those organisms capable of reducing nitrate were not significant. A seasonal variation in the numbers of bacteria were found between streams. This variation is not fully explained by drainage basin areas or related to runoff. In contrast, within each stream counts varied with season and could be related to runoff. Bacterial populations which indicate fecal pollution were low and probably derived from animals not man. Wet meadows and bog areas under snow may be possible sources for sulfate reducing bacteria and those organisms capable of reducing nitrate.
    • Horses and Cattle Grazing in the Wyoming Red Desert. II. Dietary Quality

      Krysi, L. J.; Sowell, B. F.; Hubbert, M. E.; Plumb, G. E.; Jewett, T. K.; Smith, M. A.; Waggoner, J. W. (Society for Range Management, 1984-05-01)
      Botanical composition of horse and cattle diets from fecal analysis and nutrient quality of hand-harvested forages used by these herbivores were evaluated to assess dietary quality during the summer and winter seasons of 1981 in the Wyoming Red Desert. Dietary crude protein estimates averaged 7.5 +/- 0.1% and 9.0 +/- 0.5% during the summer for horses and cattle, respectively. Dietary crude protein estimates in the winter were lower, averaging 6.1 +/- 0% and 6.0 +/- 0% for horses and cattle, respectively. Estimated dietary calcium levels for both herbivores were high through the summer and winter, while dietary phosphorus levels appear to be deficient during both seasons. Average in vitro dry matter disappearance coefficients for horses and cattle during the summer were 52 +/- 2% and 52 +/- 2%, respectively. During the winter these values dropped to 39 +/- 1% and 40 +/- 1% for horses and cattle, respectively.