• Effect of Desert Termites on Herbage and Litter in a Shortgrass Ecosystem in West Texas

      Bodine, M. C.; Ueckert, D. N. (Society for Range Management, 1975-09-01)
      The desert termite, Gnathamitermes tubiformans, is an important insect on rangelands in the southwestern United States. Population densities of this insect averaged 2139/m2 in the upper 30 cm of soil in a shortgrass community in West Texas over a 3-year period and reached a peak of 9127/m2 The live biomass of termites averaged 5.2 g/m2 and reached a peak of 22.21 g/m2. In a laboratory study, desert termite workers consumed 2.4% of their live body weight/day of dry buffalograss leaves. In field studies, control of desert termites with insecticide resulted in a 22% increase in standing crop of grass and a 50% increase in litter accumulation by the end of the second growing season after control was initiated. Termite-free plots had almost three times more litter than termite-infested plots after four growing seasons. Desert termites accounted for 55% of the disappearance of litter from the soil surface. Ranchers can expect higher population densities of desert termites and hence greater consumption of forage and litter during wet years.
    • Economics of Ranch Management Alternatives in Southwestern North Dakota

      Leistritz, F. L.; Qualey, N. J. (Society for Range Management, 1975-09-01)
      The fundamental management problem of northern plains ranchers is to increase ranch income while maintaining or improving the productivity of the range resource. This study used linear programming to evaluate the profitability of alternative range and livestock management practices. Sale of yearlings was found to be more profitable than selling calves. Establishment of crested wheatgrass for spring grazing allowed deferment of native range and was profitable if yearling prices exceeded $40 per cwt. Fertilization of crested wheatgrass pastures and native hayland at a rate of 40 pounds actual nitrogen per acre was profitable, but native range fertilization was not profitable using prices for the 1970-73 period. Recent price trends place added emphasis on efficient use of the range resource.
    • Constituents of In Vitro Solution Contribute Differently to Dry Matter Digestibility of Deer Food Species

      Uresk, D. W.; Dietz, D. R.; Messner, H. E. (Society for Range Management, 1975-09-01)
      This study assessed the contribution of chemical constituents used in the in vitro technique by Tilley and Terry on digestibilities of five species of plants. Apparent digestibility was lowest, 28-29%, for water alone, buffer alone, and buffer plus pepsin. Dry matter loss increased to 32-33% with either buffer + alcohol + HCl or buffer + alcohol + HCl + pepsin. Highest apparent digestibility, 44%, was reached with the addition of white-tailed deer inoculum. HCl contributed significantly to digestion while pepsin did not. Degree of digestion varied among the five species of plants tested.
    • Chemical Control of Mesquite Regrowth of Different Ages

      Beck, D. L.; Sosebee, R. E.; Herndon, E. B. (Society for Range Management, 1975-09-01)
      Herbicide effectiveness on different age resprouts of honey mesquite was studied in the Rolling Plains of Texas. Herbicide treatments consisting of 2,4,5-T amine, 2,4,5-T ester, and Tordon 225 Mixture were applied monthly (May 15, 1972, through August 15, 1972) to trees shredded in 1971, 1965, and 1958. Tordon 225 Mixture was most effective on resprouts of all ages throughout the study. Trees sprayed in May and June had a higher percent root mortality than trees sprayed in either July or August.
    • A Comparison of Three Methods of Estimating Digestibility for Determining Intake of Grazing Cattle

      Handl, W. P.; Rittenhouse, L. R. (Society for Range Management, 1975-09-01)
      In vitro plus pepsin digest (IVP), lignin ratio (LR), and in vitro plus neutral detergent digest (IVND) were of about equal value in estimating digestibility of spring forage grazed by steers, provided the limitations of each were considered. However, when these methods of estimating digestibility were used to estimate intake, only the IVP and LR methods gave realistic results. The IVND results were lower than the expected physical capacity of the animals, and indicated further study of this method is needed.