• Low-energy Grubbing for Control of Junipers

      Wiedemann, H. T.; Cross, B. T. (Society for Range Management, 1981-05-01)
      Low-energy grubbing was effective and economical in controlling sparse to moderate stands of junipers infesting rangeland. A small, 48.5-kW (65-hp), shift-on-the-go crawler tractor, as compared to tractors larger than 74.5kW (100-hp) normally used, was adapted for grubbing by attaching a U-shape blade to the front mounted C-frame for root cutting at depths of 15 to 30 cm. A 98% plant kill was achieved because uprooting of trees below the bud-zone prevented sprouting. The newly designed hydraulic attachment significantly improved tree uprooting. Grubbing rate was a curvilinear function of juniper density and varied approximately from 4.0 to 0.5 ha/hr (10 to 1.25 ac/hr) to remove 80 to 500 trees/ha (30 to 200 trees/acre). Cost varied from $6.00 to $50.00/ha ($2.40 to $20.00/acre).
    • Response of Bobwhites to Cover Changes within Three Grazing Systems

      Hammerquist-Wilson, M. M.; Crawford, J. A. (Society for Range Management, 1981-05-01)
      In south Texas bobwhites responded to short-term changes in the amount of vegetative cover within three grazing systems, two rotational and one continuous. Use by quail apparently was related to increases in amounts of bare ground and forb cover and decreases in grass cover.
    • Sediment Production as Influenced by Livestock Grazing in the Texas Rolling Plains

      Wood, M. K.; Blackburn, W. H. (Society for Range Management, 1981-05-01)
      The influence of livestock on sediment production was evaluated on a Clay Flat range site with shrub canopy areas, and midgrass and shortgrass interspace areas in the Rolling Plains near Throckmorton, Texas. Sediment production in the shrub canopy areas was similar across grazing treatments of heavy and moderate stocking, continuous grazing; rested and grazed deferred-rotation; rested and grazed high intensity, low frequency (HILF); and two livestock exclosures which had not been grazed for 20 years. Sediment production from the shortgrass interspace area was similar for all grazing treatments except from the heavily stocked, continuously grazed pasture, where sediment production exceeded that of the rested HILF treatment. The midgrass interspace sediment production for the heavily stocked, continuously grazed treatment exceeded that of the deferred-rotation treatments and the exclosures. Likewise, sediment production for the grazed HILF treatment was greater than that for the rested deferred-rotation treatment and exclosure. Soil and vegetation variables which significantly influenced sediment production included aggregate stability, organic matter content, mulch, standing crop, bulk density, and ground cover.
    • White-tailed Deer Diets from Pastures in Excellent and Poor Range Condition

      Bryant, F. C.; Taylor, C. A.; Merrill, L. B. (Society for Range Management, 1981-05-01)
      A study was initiated in August, 1975, to examine the forage available to and diet composition of white-tailed deer on pastures of excellent and poor range condition at the Sonora Research Station near Sonora, Texas. Grass and forb standing crop and deer feeding time on these two forage classes were considerably higher on the pasture in excellent range condition than that in poor range condition. Browse standing crop and feeding time was greater from the pasture in poor range condition. The Merrill 4-pasture grazing system appeared to increase the availability and use by deer of grass regrowth. Yearly averages of crude protein and phosphorus were higher in diet samples collected from the pasture in excellent range condition. Digestible energy levels were similar between pastures when averaged over the 1-year period. Digestible energy levels in diets were, however, higher from the excellent condition pasture in every season except winter. In winter, deer fed primarily on the foliage of oak on excellent condition range; but on the pasture in poor range condition, deer used large amounts of foliage and mast from juniper and dead leaves of persimmon in addition to oak foliage. Juniper and persimmon apparently contributed to the higher digestible energy levels observed on the pasture in poor range condition during the winter season. Energy may be a major nutrient limiting deer production on the Edwards Plateau.