• The Chemical Constituents of Sagebrush Foliage and Their Isolation

      Kelsey, Rick G.; Stephens, Jeffrey R.; Shafizadeh, Fred (Society for Range Management, 1982-09-01)
      Five foliar constituents were measured seasonally from the three subspecies of big sagebrush in Montana. Monoterpene, crude terpenoid, and crude fat levels were lowest in the spring, increased through the summer with maximum quantities at flowering or in the fall and winter months thereafter. Crude protein and total nonstructural carbohydrates were at highest concentrations in the spring, decreased in the summer, and rose again in the fall. Sagebrush foliage consists of an external and internal component. The external material is glandular secondary metabolic products, primarily terpenoids, and cuticular waxes. The internal constituents are cell-wall polymers, protein, nonstructural carbohydrates, and lipids. A 5-minute chloroform extraction of fresh whole leaves removed the external material (crude terpenoids) with minimal affect on the internal components. Steam distillation extracted the epidermal terpenoids and the internal nonstructural carbohydrates leaving the cuticular waxes and protein in the dry matter residue.
    • The Suitability of Legumes for Rangeland Interseeding and as Grasshopper Food Plants

      Hewitt, George B.; Wilton, A. C.; Lorenz, R. J. (Society for Range Management, 1982-09-01)
      Fifteen legume varieties (selections representing 7 species) which have some potential for reseeding into rangeland were evaluated in the laboratory and in the field as to their suitability as food plants for several species of rangeland grasshoppers. Varieties of alfalfa, trefoil, and cicer milkvetch were less preferred than varieties of sanfoin, sweetclover, hairy vetch, and crown vetch. Three plant varieties, alfalfa (Mandan composite-1), birdsfoot trefoil (Cree), and cicer milkvetch (Mandan Composite-2) were the least preferred of the varieties tested based on the rate of grasshopper development and weight of adults reared on the test plants, the time spent feeding during a 30-min period, and plant mortality and % leaf reduction in a field test. Alfalfa appeared to have the greatest potential for reseeding on arid rangeland sites. Nonpreference is the main resistance factor that should be used when screening rangeland plants for grasshopper feeding preferences.
    • Training Needs for Quantifying Simulated Diets from Fragmented Range Plants

      Holechek, Jerry L.; Gross, Bryan (Society for Range Management, 1982-09-01)
      A procedure is described that results in rapid training of observers for microhistological analysis. Observers trained using this procedure were able to evaluate accurately 6 hand-compounded diets comprised of semidesert plant species. The accuracy of microhistological analysis was examined by using the 4 trained observers to evaluate 26 additional hand-compounded diets containing various combinations of 30 different grasses, forbs, and shrubs from semidesert range. The relationship between relative density (estimated percent by weight composition) and actual percent by weight composition was close to unity for species in each forage class individually or in combination. However this relationship would probably have been different if the observers had not used known diets to evaluate their accuracy and make corrections. It is recommended that all technicians using microhistological analysis regularly check their accuracy with hand-compounded diets.
    • Two-step Sampling Technique for Estimating Standing Crop of herbaceous Vegetation

      Anderson, D. M.; Kothmann, M. M. (Society for Range Management, 1982-09-01)
      Standing crop of vegetation may be estimated by sampling foliar cover per unit area and then determining mass per unit of cover. Multiplying foliar cover per unit area by mass per unit of cover gives mass per unit area (standing crop). By this method standing crop is estimated rapidly with low variance while minimizing the amount of actual harvesting required. Standing crop of both major and minor species can be estimated adequately without over sampling major species and under-sampling minor species. The technique is most easily applied to herbaceous plant communities of low stature.
    • Use of Historical Yield Data to Forecast Range Herbage Production

      Hanson, C. L.; Wight, J. R.; Smith, J. P.; Smoliak, S. (Society for Range Management, 1982-09-01)
      An analysis of the 51-year herbage yield series from the Many-berries Range Experimental Farm in southeastern Alberta showed that there was a slight dependency between current year's herbage yield and previous year's yield. The analysis showed that the conditional probability of a below-average yield following a below-average yield year was about the same as the unconditional probability of having a below-average yield in any given year. The conditional probability of an above-average yield following a year with a below-average yield was significantly below the unconditional probability of having an above-average yield in any year. The probability of an above-average yield following a year with an above-average yield was significantly greater than the unconditional probability.
    • Waterponding for Increasing Soil Water on Arid Rangelands

      Tromble, John M. (Society for Range Management, 1982-09-01)
      Ponding dikes constructed to slow and control the overland flow of runoff water were evaluated. Infiltration and runoff measurements from a sprinkling infiltrometer indicated no differences between the control and the water ponding area. Examination of 20 years of precipitation records for June through September showed that enough ponding events occurred to supply an adequate amount of water for wetting the soil profile to below the plant rooting zone. The control areas were low in available soil water even immediately following precipitation events.
    • Wind Erosion Curtailed by Controlling Mesquite

      Gould, Walter L. (Society for Range Management, 1982-09-01)
      A sand-dune mesquite area with very little interdunal vegetation was treated aerially one to three times with 2,4,5-T at 0.56 kg/ha in an oil:water emulsion. Four and five years after the initial treatment, the amount of blowing soil was evaluated using sandtraps located at various distances from the boundary between sprayed and unsprayed mesquite. The amount of wind-blown particles was greatly reduced on the area chemically treated to control mesquite. During the windy season the amount of blowing soil in the unsprayed area was more than 15-fold greater than at 180 m into the sprayed area. Intermediate amounts were measured between the boundary and 180 m into the treated area.