• Short Duration Grazing at the Texas Experimental Ranch: Weight Gains of Growing Heifers

      Heitschmidt, R. K.; Frasure, J. R.; Price, D. L.; Rittenhouse, L. R. (Society for Range Management, 1982-05-01)
      Total and average daily gains of Hereford/Angus crossbred growing heifers were contrasted between a continuously grazed (CG) treatment and a 10-pasture, 1-herd rapidly rotated short duration grazing (SDG) treatment. Stocking rate in the CG was 0.48 ha/AUM, a moderate rate, while stocking rate in the SDG treatment was 0.24 ha/AUM. Trials were conducted during the 1978 and 1979 growing seasons. Both total and average daily gains were similar in both treatments both years. Because of the two-fold difference in rate of stocking, production/ha was approximately double in the SDG to that in the CG treatment. It is tentatively concluded from the results of this and previous studies that a properly managed SDG system may satisfactorily support livestock at rates of stocking appreciably greater than that normally expected from conventional grazing schemes.
    • Short Duration Grazing at the Texas Experimental Range: Effects On Forage Quality

      Heitschmidt, R. K.; Gordon, R. A.; Bluntzer, J. S. (Society for Range Management, 1982-05-01)
      Variation in percent crude protein (% CP) of available forage was examined at the Texas Experimental Ranch as a function of grazing treatment, plant species, physiological age of plant tissue, and season. Results indicate that % CP content varied as much as function of physiological age of plant tissue as a function of plant species. Although quantity of crude protein of total standing crop averaged significantly more in an ungrazed treatment than in a short duration grazing treatment, % CP was generally greater in the grazed than the ungrazed treatment. It is suggested that an increase in quality of forage may be a primary mechanism facilitating energy flow through short duration grazing systems whereby dramatic increases in livestock carrying capacity may be realized.
    • Soil Loss, Runoff, and Water Quality of Seeded and Unseeded Steep Watersheds Following Prescribed Burning

      Wright, H. A.; Churchill, F. S.; Stevens, W. C. (Society for Range Management, 1982-05-01)
      Seeding of steep slopes (37 to 61%) after burning on the Edwards Plateau in central Texas reduced soil losses 78 to 93%. Moreover, the major impact of burning on soil losses was significantly reduced in 3 months on burned and seeded watersheds, but not for 15 to 18 months on unseeded watersheds. Stability (soil losses comparable to pretreatment levels) was reached in 6 months on burned and seeded watersheds. Soil loss rates stabilized when cover (live vegetation plus litter) reached 64 to 72% during normal to wet years or 53 to 60% during dry years. Thus, amount of precipitation and cover are closely tied to soil losses. Overland flow stabilized in 4 to 5 years on unseeded watershed and in 1 to 2 years on seeded watersheds. Water quality, lowered slightly by burning, returned to preburn levels within 2 years after seeding. Without seeding it took 4 years to reach preburn levels. Overall, water quality change following burning was not considered to be serious.
    • Punch Planting to Establish Grass Seed

      Hauser, V. L. (Society for Range Management, 1982-05-01)
      Perennial grasses are difficult to establish from seed in the Southern Great Plains. The conventional planting practice is to plant grass seeds 1 to 2 cm deep in the soil; but that soil layer often dries quickly, thus preventing plant establishment. I investigated punch planting, which may avoid the problem of soil drying around grass seeds. Punch planting is defined as the placement of seeds in open, small-diameter holes, punched in the soil to a much greater depth than conventional planting. Under drying conditions, punch planting produced satisfactory stands for 5 grasses, but conventional planting produced failures. Where the soil was kept wet, both methods produced satisfactory grass stands. Optimum depth of punch planting was related to seed size and seedling vigor. Small-diameter holes (0.6 cm) produced best plant emergence, because soil at the bottom of these holes dried slower than at the bottom of large holes. Punch planting may offer a solution to the problem of seeding failures.
    • Understory Herbage Production as a Function of Rocky Mountain Aspen Stand Density

      Woods, R. F.; Betters, D. R.; Mogren, E. W. (Society for Range Management, 1982-05-01)
      The effects of aspen overstory basal area on herbaceous understory production on the Bears Ears District of the Routt National Forest in northwest Colorado were investigated. Using regression, a coefficient of determination of .61 was found between herbage production and overstory basal area. For overstory basal areas less than 10.0 meter2}/hectare, herbaceous understory production varied considerably and was often double that found at higher densities of overstory basal area. Herbage production at higher densities (10.0 to 18.9 $m2/ha) showed less variation with an average production of 1100 kilograms/hectare. The best opportunities for herbaceous understory production in unmanaged, pure aspen stands occur at overstory basal areas less than 10.0 m2/ha.
    • Vegetation Response to Prescribed Fire in a North Florida Flatwoods Forest

      Moore, W. H.; Swindel, B. F.; Terry, W. S. (Society for Range Management, 1982-05-01)
      Selected naturally regenerated flatwoods forests were burned in preparing a large, long-term study of the effects of several multiple use management practices on forest vegetation and wildlife. Early effects of burning on understory vegetation are reported here. Fire reduced woody understory coverage (from 72 to 66% of surface area), and increased herbaceous species frequency (from 60 to 81%) and herbaceous standing biomass (from 124 to 245 kg/ha). Graphical analyses show an increase in herbaceous species diversity as a result of burning.
    • Efficiency of Forage Harvest by Grazing Cattle

      Allison, C. D.; Kothmann, M. M.; Rittenhouse, L. R. (Society for Range Management, 1982-05-01)
      Three grazing trials of 14 days each were conducted in April, July, and September, 1977, to examine the effects of grazing pressure on forage disappearance, organic matter intake, and the relationship between intake and forage disappearance. Levels of grazing pressure studied were 10, 20, 40, and 50 kg of forage allowed per animal-unit per day (kg/au/da). Standing crop was measured before, during the middle, and immediately after each trial. Organic matter intake was estimated at the beginning and end of each trial by the fecal excretion:indigestibility ratio technique. Total standing crop declined steadily during the grazing trials, with forage availability being significantly less at the end than at the beginning or middle of the trials. Averaged over the three trials, total forage disappearance during a 14-da grazing period was 236, 334, 355, and 457 kg per pasture and forage losses per au per day were 8.5, 12.0, 12.7, and 16.3 kg for the 10, 20, 40, and 50 kg/au/da grazing pressures, respectively. However, daily intake averaged across all treatments, periods, and trials was approximately 9 kg/au/da. At the grazing pressure level of 10 kg/au/da, forage disappearance approximated the average daily intake, whereas, grazing pressures of 20, 40, and 50 kg/au/da had forage disappearances that exceeded intake by 28, 48, and 90%, respectively. These data indicate a possibility for a two-fold increase in the efficiency of forage harvest by grazing cattle as grazing pressure is increased.
    • Forage Production and Removal from Western and Crested Wheatgrasses Under Grazing

      Hart, R. H.; Balla, E. F. (Society for Range Management, 1982-05-01)
      Forage production and removal from tillers of western wheatgrass (Agropyron smithii Rydb.) and crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult.] were studied at two stocking rates with long-interval time-lapse photography. As stocking rate increased, frequency of grazing increased markedly, but the proportion of available herbage removed at each grazing event increased only in 1977 on western wheatgrass. Forage production per tiller of western wheatgrass was usually higher under light than under heavy stocking, and in one year production of grazed tillers under light stocking was often higher than production of ungrazed tillers. Production per tiller of crested wheatgrass under grazing was marginally less than that per ungrazed tiller, with no difference between stocking rates. Patterns of forage removal with grazing were markedly different from those with clipping, and removal with grazing was much less severe than that imposed in most clipping studies reviewed.
    • Effect of Continuous Grazing on the Diet of Steers

      Yates, D. A.; Clanton, D. C.; Nichols, J. T. (Society for Range Management, 1982-05-01)
      Continuous grazing of Sandhill native forage at a normal stocking rate in late August had no effect on organic matter intake (OMI), but the protein content and in vitro organic matter digestibility (IVOMD) declined over a 3-week period. The average OMI was 75 g/kg W^.75. As the availability of forage declined, the ability of the steers to selectively graze was apparently reduced. Similarly, continuous grazing of mixed prairie-type range from October 30 to March 13 had no effect on OMI but the protein content of the diet was reduced. The IVOMD did not change during the winter grazing trial. The average OMI was 66 g/kg W^.75 Steer calves gained .24 kg daily during the grazing period.