• Diets of Domestic Sheep and Other Large Herbivores in Southcentral Colorado

      MacCracken, J. G.; Hansen, R. M. (Society for Range Management, 1981-05-01)
      The botanical composition of herbage consumed by domestic sheep, mule deer, domestic cattle and elk from critical big game winter ranges in southcentral Colorado was studied using the fecal analysis technique. The food habits of domestic sheep grazed during the late spring overlapped those of mule deer by 15%, elk 46%, and domestic cattle by 53%. Mule deer diets were 10% similar to cattle and 30% to elk. Elk and cattle diets averaged 39% identical on the study area. The low similarity in diet between domestic stock and mule elk suggests that livestock grazing in the study area could be made compatible with the winter range needs of mule deer, but the potential competition between elk and domestic stock needs additional study.
    • Diet Selection of Hereford, Angus X Hereford and Charolais X Hereford Cows and Calves

      Walker, J. W.; Hansen, R. M.; Rittenhouse, L. R. (Society for Range Management, 1981-05-01)
      Botanical composition of cattle diets of Hereford, Angus x Hereford and Charolais x Hereford cows and calves were compared to determine the effect of cattle age and/or breed on species selection. Multivariate analysis of variance showed small but significant differences between cow and calf diets and no differences among breeds. Similarity indices and Spearman's rank correlation coefficient showed a high degree of overlap and significant correlation between ages and among breeds. Differences between cow and calves among breeds were minor and of little value in range management.
    • Diameter-Length,—Weight Relations for Blackbrush [Coleogyne ramosissima] Branches

      Provenza, F. D.; Urness, P. J. (Society for Range Management, 1981-05-01)
      Regression was used to relate branch diameter to branch length (r = 0.85) and weight (r2=0.94) for blackbrush plants in southwestern Utah. These regression equations were subsequently used to estimate blackbrush utilization by domestic goats in a browsing study. The diameter-length equation compared favorably with before-and-after measurements for accuracy and greatly reduced man-hour costs in determining utilization. Estimates of utilization based on the diameter-weight equation were less than estimates based on the before-and-after approach or the diameter-length equation; the diameter-weight equation accounted for leaves and thus provided a more accurate estimate of utilization.
    • Deer and Elk Use on Foothill Rangelands in Northeastern Oregon

      Miller, R. F.; Krueger, W. C.; Vavra, M. (Society for Range Management, 1981-05-01)
      Forested foothills of the Wallowa Mountains in northeastern Oregon provide spring and early summer range for deer and elk. Deer and elk use varied both between plant communities and seasonally within plant communities. Plant species composition of big game diets also varied with season. Bunchgrass and logged communities collectively occupying 57% of the land area studied, provided 90% of the big game diet during spring and early summer. Grasses made up 52% of the diet, forbs 38%, and browse 10%. Timothy and western goatsbeard were the two most important species consumed by big game. Pellet groups did not reliably estimate the value of various communities to deer and elk for forage use.
    • Comparison of Herbage Production on Moderately Grazed and Ungrazed Western Ranges

      Lacey, J. R.; Van Poollen, H. W. (Society for Range Management, 1981-05-01)
      The hypothesis that there is no difference in the total amount of herbage produced on moderately grazed and ungrazed Western ranges was proposed and rejected. It was rejected because published literature shows that annual herbage production averaged 68 +/- 46% higher when plots were protected from a moderate level of livestock grazing. Likewise, herbage production of individual plants averaged 59 +/- 50% higher when they were protected, rather than clipped at a moderate level of use.
    • Application of Remote Sensing to Prairie Dog Management

      Dalsted, K. J.; Sather-Blair, S.; Worcester, B. K.; Klukas, R. (Society for Range Management, 1981-05-01)
      The areal extent of prairie dog towns in Wind Cave National Park (WCNP) has increased at an alarming rate in the past 20 years. An inventory method was needed to replace the time and labor intensive ground survey method, i.e. rod and transit. Color infrared (CIR) aerial photography (1,370 m above ground) provided a useful product for rapidly and accurately delineating prairie dog towns. Extent was determined by measurements on the CIR film to be 608 ha or 5.3% of the total WCNP area. Ground measurements, taken near the time of the aircraft overflight, included general vegetation description of each prairie dog town and a vegetation sampling from 0.25 m2 plot on a stratified, random basis. The ground data helped explain and identify the variations recorded on the CIR film. Soil and topographic information were used with the CIR film to determine likely expansion potential and probable direction of growth of the 11 major prairie dog towns in WCNP. The prairie dog town inventory and expansion potential of each town has probable usefulness in the development of management plans.