• Cow-Calf Response to Stocking Rates and Grazing Systems on Native Range

      Kothmann, M. M.; Mathis, G. W.; Waldrip, W. J. (Society for Range Management, 1971-03-01)
      Studies of grazing management for cow-calf operations on native range have been conducted on the Texas Experimental Ranch since 1960. Three stocking rates and three grazing systems were evaluated. Calf production was greater from the deferred-rotation grazing systems than from continuous grazing at the same stocking rate. Heavier stocking rates reduced calf production per animal unit slightly, but production per acre increased significantly. The net returns per animal unit were greatest from the Merrill system, stocked at a moderate rate, and the net returns per acre were greatest from heavy continuous stocking. The optimum stocking rate for this range appeared to be between 40 and 50 animal units per section and it was profitable to use the Merrill grazing system./Se llevó a cabo un estudio en el rancho experimental de Texas cerca de Throckmorton, Texas, E.U.A., comprendiendo un período de diez años. Los tratamientos fueron: pastoreo todo el año a tres diferentes cargas de animales: pesado (12.8 acres por vaca), moderado (20.8 acres por vaca), ligero (28.4 acres por vaca) y dos diferentes sistemas de pastoreo con rotación a la carga moderada. La producción de becerras por vaca fué mas alta para los sistemas de pastoreo con rotación que para el pastoreo por todo el año a la misma carga moderada. La producción por vaca fué menor en el tratamiento de pastoreo todo el año a la carga pesada pero la producción por acre fué mayor que en todos los otros tratamientos. También el ingreso neto por acre. El ingreso neto por vaca fué mayor en el cuarto potrero rotación llamado Sistema de Merrill. El coeficiente de agostadero óptimo fué entre 12.5 y 15 acres por unidad animal.
    • Influence of Rootplowing and Seeding on Composition and Forage Production of Native Grasses

      Mathis, G. W.; Kothmann, M. M.; Waldrip, W. J. (Society for Range Management, 1971-01-01)
      Effects of rootplowing, with or without seeding, on forage production and composition of native grasses were determined on a deep upland range site. Percent composition of stoloniferous species, particularly buffalograss, was reduced initially and after 6 growing seasons by the rootplowing treatments. Frequency counts indicated a reduction of Texas wintergrass on rootplowed plots (seeded and nonseeded) compared to an undisturbed, native check area. This reduction the first growing season was attributed to the competitive effect of sorghum almum introduced in the seeding mixture. Unsuccessful establishment of other seeded grasses (sideoats grama and switchgrass) appeared to be related to poor seedbed preparation, competition from sorghum almum plants, and below normal rainfall immediately after seeding. Rootplowing decreased grass production. After 6 growing seasons, significantly less forage per acre was produced on rootplowed-seeded plots than on nonrootplowed plots. Differences in forage production were related to plant composition and density. /// El estudio fué empezado en el año de 1964 en el rancho experimental de Texas en el Municipio de Throckmorton; el diseño incluyó testigo; y se pasó arado para desenraizar sin la siembra y se pasó arado para desenraizar con la siembra. Después de 6 años los dos tratamientos disminuyeron la producción de forraje y composición de zacates deseables. El zacate sorghum almum (Sorghum almum) apareció en la siembra. El arado desenraizador controló el mezquite (Prosopis glandulosa var. glandulosa).
    • Sideoats Grama as an Indicator of Grazing Intensity and A Method of Determining Its Utilization

      Waldrip, W. J. (Society for Range Management, 1965-09-01)
      Sideoats grama is a key species for indicating forage use on the Rolling Plains of Texas. A regression equation for field determination of percent utilization of sideoats grama was developed and tested. The method developed, based on measurements of total height and stubble height, is more rapid and accurate than other methods commonly used by technicians.