• Yearly Variation in Germination in Three Subspecies of Big Sagebrush

      Harniss, R. O.; McDonough, W. T. (Society for Range Management, 1976-03-01)
      Yearly variation in germination between individual plants of three subspecies of big sagebrush (Artemisia tridentata) was examined. The subspecies vaseyana germinated less than tridentata or wyomingensis. Only tridentata showed a significant difference in year-to-year variation. In all years, germination rates of the three subspecies were high enough to exclude seed germination as a limiting factor in sagebrush reinvasion.
    • Water Quality Implications of Cattle Grazing on a Semiarid Watershed in Southeastern Utah

      Buckhouse, J. C.; Gifford, G. F. (Society for Range Management, 1976-03-01)
      During 1973 and 1974 wildland water quality analyses were performed on a semiarid, chained and seeded, pinyon-juniper site in southeastern Utah. The area was treated in 1967 and protected from grazing until 1974. In 1974 livestock grazing was introduced and investigations continued to determine if any deleterious land use effects were present from fecal contamination by cattle. No significant changes were noted in fecal and total coliform production (fecal pollution bacterial indicators) from grazing use. There is an element of risk involved whenever data generated from a small area are projected to larger land areas. However, it appears that this level of livestock grazing (2 ha/AUM) did not constitute a public health hazard in terms of fecal pollution indicators on the semiarid watershed.
    • Three-Dimensional Chlorophyll Concentrations in a High Biomass Blue Grama Canopy

      Tucker, C. J.; Garratt, M. W. (Society for Range Management, 1976-03-01)
      The three-dimensional chlorophyll variation in 50-cm high blue grama canopy was investigated. Statistical analysis revealed significant differences in the vertical dimension and a quadratic relationship between chlorophyll density and height. Maximum canopy chlorophyll concentrations occurred in the 12.5-25.0 cm vertical region with the lowest concentrations occurring in the 0.0-12.5 cm and 37.5-50.0 vertical region.
    • Site Relations, Regrowth Characteristics, and Control of Lotebush with Herbicides

      Scifres, C. J.; Kothmann, M. M. (Society for Range Management, 1976-03-01)
      Regrowth following top removal of lotebush (Condalia obtusifolia (Hook.) Weberb.) seedlings and field transplants followed a typical apical dominance pattern. When 2.5 cm of the stem segments were left intact, sprouting occurred from stem tissues. When stems were completely removed, sprouts originated from root tissues. Lotebush densities on the Texas Experimental Ranch were greater on shallow redland than on deep upland, rolling hill, rocky hill or valley range sites. Aerial application of 2,4,5-T at 1.12 kg/ha was ineffective for control of lotebush, regardless of range site. Basal sprays containing 4 or 8 g/liter of 2,4,5-T + picloram in a diesel oil:water emulsion (1:4) effectively controlled lotebush. Basal sprays of dicamba were less effective than 2,4,5-T + picloram; and 2,4,5-T was ineffective in the emulsion carrier. However, 2,4,5-T in diesel oil reduced the canopies by an average 50 to 70% at 2 years after treatment. At rates greater than 5 g (active ingredient)/m of canopy diameter, monuron pellets reduced lotebush canopies by 85 to 100%. At the same rate, dicamba granules completely reduced the brush canopy and resulted in 86% root kill at 2 years after application. Two g/m of canopy diameter of picloram pellets completely controlled the lotebush.
    • Seasonal Response of Macartney Rose and Huisache to Herbicides

      Meyer, R. E.; Bovey, R. W.; Riley, T. E.; Flynt, T. O. (Society for Range Management, 1976-03-01)
      Picloram granules and sprays were applied to Macartney rose (Rosa bracteata Wendl.) and huisache (Acacia farnesiana (L.) Willd.) in the claypan area of Texas. Monthly granule applications to Macartney rose were generally least effective in the summer. Rates of 1, 2, and 3 lb/acre of picloram as granules reduced the canopy 53, 68, and 86% and killed 14, 32, and 57% of the plants, respectively. Foliar sprays of picloram were about equally effective as granules. Huisache was not as highly responsive to picloram as to either granules or soil sprays at rates up to 4 lb/acre. However, picloram at 2 lb/acre as a foliage spray in May or September killed 90% or more of the plants. A 1 lb/acre foliage spray of picloram combined with a 1 lb/acre spray of 2,4,5-T, dicamba, or picloram in the soil also killed 53% or more of the huisache plants.
    • Responses of Andropogon Pumilus Roxb. to Various Heights and Intervals of Clipping

      Singh, V. P.; Mall, L. P. (Society for Range Management, 1976-03-01)
      Andropogon pumilus Roxb. produced most dry matter (above ground and underground) when it was clipped at an interval of 45 days and at height of 15 cm. The average seed output at this clipping was maximum.
    • Response of Switchgrass (Panicum virgatum L.) to Clipping Frequency

      Beaty, E. R.; Powell, J. D. (Society for Range Management, 1976-03-01)
      The native grasses are not widely grown for cultivated pastures in the South but are important forage producers in the United States. Their responses to frequency of clipping are not widely known and appear to be significantly different from that of the introduced cultivars, Bermudagrass (Cynodon dactylon) and Bahiagrass (Paspalum notatum). The introduced species, however, are slow to initiate growth in the spring, and it appears that the forage program in the South could be improved significantly by grazing switchgrass before the summer perennials initiate growth. Haying at flowering and grazing following frost could utilize the switchgrass later in the summer. Pangburn switchgrass (Panicum virgatum L.), a native species, tolerated one clipping during the season with little or no reduction in forage production, clonal survival, tiller number per clone, or tiller height. However, two or more clippings per season reduced all of the above. Over-utilization of switchgrass at the start of the season decreased the number of tillers and clones per plot and resulted in a serious weed problem.
    • Red Meat Production on U.S. Rangelands

      Mitchell, John E. (Society for Range Management, 1976-03-01)
    • Rainfall Interception by Cool-desert Shrubs

      West, N. E.; Gifford, G. F. (Society for Range Management, 1976-03-01)
      Interception patterns of big sagebrush (Artemisia tridentata Nutt.) and shadscale (Atriplex confertifolia (Torr.) Wats.) were measured under two simulated rainfall intensities during three different seasons. Mean rainfall interception rate of individual plants of both species was 0.15 cm when averaged over all sampling dates and rainfall intensities. Interception during individual storms of at least 0.15 cm size by entire plant communities, based on measured vegetal cover, was calculated at 0.028 cm or less. On the average, about 4% of the total annual rainfall (not snowfall) would be intercepted by these plant communities.
    • Predation on domestic sheep in northeastern Nevada

      Klebenow, D. A.; McAdoo, K. (Society for Range Management, 1976-03-01)
      A northern Nevada range band of sheep was studied in order to verify the extent of losses to predation and to other causes. Daily searches were made for losses and carcasses were autopsied. During lambing, predator losses varied on the two operations studied, 1 loss per 14 days in one case and 1 loss per day in the other. Losses from other causes were high at that time. Predation increased in late summer and continued to be high into the fall. Predation was the major cause of loss at that time. Winter losses were variable. In one short period, 38 head of sheep were lost to halogeton (Halogeton glomeratus). In one annual production cycle 9% of the band was the total verified loss. The verified predator loss was 4% of the band. The coyote (Canis latrans) accounted for 91% of the total predation.
    • Poisoning in Sheep from Emory Milkvetch and Nitro Compounds

      Williams, M. C.; James, L. F. (Society for Range Management, 1976-03-01)
      Sheep were fed nitro-containing Emory milkvetch (Astragalus emoryanus) and infused intravenouslv with 3-nitro--1-propanol and 3-nitropropanoic acid. Emory milkvetch and the nitro compounds produced similar clinical syndromes. Nitro compounds, therefore, appear to be the principal toxic constituent in Emory milkvetch.
    • Morpa weeping lovegrass produces more beef

      Shoop, M.; McIlvain, E. H.; Voigt, P. W. (Society for Range Management, 1976-03-01)
      Morpa, a new variety of weeping lovegrass (Eragrostis curvula (Schrad.) Nees), increased yearly gain per steer 33 lb, or 12%, in a 3-year grazing comparison with Common weeping lovegrass at Woodward, Oklahoma. Because steer gains were greater, Morpa produced $12.00, or 170%, more profit per acre. Also, Morpa had the same high carrying capacity as Common; was equally adapted to withstand drouth; and required the same high level of cultural and grazing management. Morpa was slightly less winterhardy than Common.
    • Influence of Temperatures, Water Stress, and Nitrogen Treatments on Chlorophyll and Dry Matter of Western Wheatgrass

      Bokhari, U. G. (Society for Range Management, 1976-03-01)
      Western wheatgrass (Agropyron smithii Rydb.) raised from seeds was given four treatments under three temperature regimes in environment controlled growth chambers. Dry matter and chlorophyll (a + b) were determined in the shoots of these plants at 20-day intervals for 100 days. Dry matter and chlorophyll production was greater from irrigated and irrigated-plus-fertilized plants under each temperature regime than it was from control or fertilized plants. This response was more pronounced at the intermediate temperature regime (24/13 degrees C) than that at the lower (13/7 degrees C) or the higher temperature regimes (30/18 degrees C). The maximum chlorophyll increase of irrigated and irrigated-plus-fertilized plants was 350% and 395% at 24/13 degrees C while in the control and fertilized plants the increase was 251% and 176%, respectively. A positive linear relationship was found between dry matter and chlorophyll of all the plants under the three temperature regimes.
    • Improved Technique for Estimating Milk Production from Range Cows

      Bluntzer, J. S.; Sims, P. L. (Society for Range Management, 1976-03-01)
      Calf weaners, commonly called "blabs," were found to be useful devices to aid in collection of milk consumption data in range animal nutrition research. Inserting a blab in the calf's nostril prevents the calf from nursing when cow and calf are turned out to graze. Calves are then weighed, allowed to nurse, and then reweighed. The difference in the two weighings was considered to be the amount of milk consumed by the calf or produced by the cow for that time interval. This procedure is an improvement over that suggested by other investigators, as both the cow and calf remain together and graze more normally, as opposed to the calves' being penned for 12 hours.
    • Herbicide Nomenclature and Related Terminology

      Scifres, C. J. (Society for Range Management, 1976-03-01)
    • Growth and Tillering of Sand Bluestem as Affected by Exogenous Growth Regulators

      Stubbendieck, J.; McCully, W. G. (Society for Range Management, 1976-03-01)
      Two plant growth regulators that were reported to inhibit auxin transport were exogenously applied to sand bluestem seedlings. DPX-1840 and Ethrel were shown to change tillering patterns, dry matter production, and plant form. When applied at relatively low concentrations, tillering was accelerated. Larger numbers of tillers developed on plants treated at the three-leaf stage as compared with those treated at the six-leaf stage. Exogenously applied plant growth regulators often reduced tiller length, plant height, and dry matter production. DPX-1840 caused plants to have an open or spreading appearance. In addition, laminas often remained rolled and were chlorotic.
    • Effects of Water Stress and Temperature on Germination of True Mountainmahogany

      Piatt, J. R. (Society for Range Management, 1976-03-01)
      The effects of five levels of available water and four constant temperature regimes upon the germination of two ecotypic collections of true mountainmahogany (Cercocarpus montanus Raf.) were investigated. Results indicate that moisture stress significantly decreases both the rate and final amount of germination in this species. The amount of moisture stress required to cause these decreases was found to be dependent upon both the seed source and the temperature. Temperature was found to be more important in determining the rate than the amount of germination.
    • Effect of Weed Control on Forage Production in the Nebraska sandhills

      Morrow, L. A.; McCarty, M. K. (Society for Range Management, 1976-03-01)
      Plots for the control of broadleaf weeds and for the determination of forage loss due to broadleaf weeds were established in the Nebraska sandhills. Herbicides were applied in the first year, the first and second years, the first, second and third years, and the first and third years in a four-year study. Forty lb/acre of N (40-N) were applied the fourth year. Herbicide treatments included 2,4-D amine, 2,4-D ester, 2,4,5-T, and silvex at 1 and 3 lb/acre; dicamba at 1/8 or 1/4 lb/acre in combination with 2 or 1 lb/acre 2,4-D amine, respectively; and picloram at 1/16 or 1/8 lb/acre in combination with 2 or 1 lb/acre 2,4-D amine, respectively. Control of broadleaf weeds with herbicide increased forage production up to 330 lb/acre when used without N. N applied following applications of dicamba at 1/4 lb/acre combined with 1 lb/acre 2,4-D amine increased forage production up to 660 lb/acre. Total herbage production increased when N was applied, but broadleaf weed production increased when weeds were not controlled. Herbicides and fertilizer can be effectively utilized to increase forage production, but they will not correct the mismanagement that results in weedy grazing lands.
    • Deer Forage and Overstory Dynamics in a Loblolly Pine Plantation

      Blair, R. M.; Enghardt, H. G. (Society for Range Management, 1976-03-01)
      In a loblolly pine plantation in central Louisiana, forage growth was basically governed by the development of pine crowns and the corresponding reduction of light in the understory. In young stands ready for initial thinning at age 20 years, growth of herbaceous and woody vegetation was virtually precluded by the dense pine canopy. Hardwood trees, shrubs, and woody vines increased as stands were thinned every 5 years. By plantation age 30 years, a multilayered midstory was developing as hardwoods and some shrubs grew beyond the deer feeding zone. Midstory density increased directly with the intensity of pine removal, and by stand age 35 it was the principal deterrent to growth of deer forage. Herbage was not abundant.