• Wood Boring Insect Infestations in Relation to Mesquite Control Practices

      Ueckert, D. N.; Wright, H. A. (Society for Range Management, 1974-09-01)
      Wood boring insect activity in mesquite wood is of interest to fire ecologists because infested trees are much easier to burn down than uninfested trees. Wood borer tunnelling in mesquite killed by six different methods was compared over a 2-year period. Basal spraying with diesel oil + 2,4,5-T and girdling resulted in significantly more tunnelling by wood borers. Borer activity was intermediate in trees killed by basal spraying with diesel, and by burning; slight in felled trees (simulated chaining or root-plowing); and insignificant in trees top-killed by 2,4,5-T spray and in the control. Ranchers planning to use prescribed burning as a method of removing dead mesquite stems from rangeland previously treated with conventional mesquite control practices could expect a high degree of wood borer activity, and hence a greater burndown in pastures where trees have been killed in previous years by basal spraying with diesel oil + 2,4,5-T. Wood borer activity will be substantial for good burndown in trees top-killed by basal treatment with diesel oil and by burning.
    • Use of Rio Grande Plain Brush Types by White-tailed Deer

      McMahan, C. A.; Inglis, J. M. (Society for Range Management, 1974-09-01)
      The relative use of 11 major brush types and a rootplowed area by white-tailed deer was studied on the San Pedro Ranch in Dimmit County, Texas. The mesquite drainage, hackberry drainage, and guajillo scrub types were preferred by deer in fall, winter, and spring. In summer, the mesquite drainage was preferred and all other types were used about equally. The granjeno drainage, rootplowed, and mesquite savannah types were used least. The preferred brush types occurred on sandy loam soils. The composition, density (within a range of tolerance), structure, and phenology of brush were not important factors influencing selection of types by deer. The quality of typical brushlands as deer habitat appeared to be largely a function of range site. Range sites capable of high gross production of herbaceous plants deserve consideration for their value to deer in brush clearing schemes. Some brush should be left intact as screening cover on such sites to insure continuing deer populations on ranches practicing brush control in the Rio Grande Plain.
    • Spy Mesa Yields Better Understanding of Pinyon-Juniper in Range Ecosystem

      Thatcher, A. P.; Hart, V. L. (Society for Range Management, 1974-09-01)
      A 2-year study on the Spy Mesa relict of the Arizona Strip provides information concerning the natural occurrence of pinyon-juniper in range ecosystems of this area. The 40-acre relict is unique because there is a wide variety of soils and natural fires have occurred over the past 50 years. The plants have been grazed by rodents and mule deer and yet they have been inaccessible to livestock. This study reveals that, following natural fires, grass became significant in the plant community only on soils that had sandy surface textures. Pinyon-juniper was the dominant species in the absence of fire, regardless of the kind of soil. Those soils having a vesicular, massive, or platy surface layer did not produce significant quantities of grass at any stage of plant succession.