• Weight-Length Relations in Flowering Dogwood Twigs

      Halls, L. K.; Harlow, R. F. (Society for Range Management, 1971-05-01)
      Ratios of twig weight or twig plus leaf weight to twig length in flowering dogwood plants vary meaningfully by season, geographic location, and year. Where the weight of new growth is predicted from twig lengths, the ratio of weight to length should be determined for the population being studied.
    • The Status of Successional and Systems Analysis Ecology

      Collins, O. B; Smeins, P. E. (Society for Range Management, 1971-05-01)
    • Shade for Improving Cattle Grains and Rangeland Use

      McIlvain, E. H.; Shoop, M. C. (Society for Range Management, 1971-05-01)
      Shade increased summerlong gain of yearling Hereford steers on rangeland by a profitable 19 lb./head in a 4-year study. High summer humidity depressed steer gains much more than did high summer temperature. The combined effects of humidity above 45% and temperature above 85 F were especially harmful. Each "hot muggy day" reduced summerlong steer gains by 1 lb. Cattle eagerly sought shade during hot summer days. By manipulating shade, cattle were drawn to under-utilized areas of a pasture to reduce damaging spot grazing. Shade was nearly as effective as water location and supplemental feeding as a tool to promote uniform grazing within a pasture. South-facing, open sheds used as winter shelters did not increase steer gains, nor would the steers use them even during storms./El presente estudio se llevó a cabo en la estación experimental de Planicios del Sur cerca de Woodward, Oklahoma, E.U.A., durante los años de 1959-1962 comprendiendo un período de cuatro años. Este estudio incluyó sombreadores hechos a mano y novillas de la raza Hereford de un año de edad. Se encontró que los sombreadores no influyeron en la producción durante el invierno pero las ganancias en peso aumentaron en 8.6 Kgs. durante el verano. Dicho aumento amortizó en dos años el costo de los sombreadores a $9.00 (Dlls.) por novillo. Se registró mas efecto adverso en humedades altas que en las temperaturas altas. Los aumentos en peso fueron menores con mas de 45% de humedad relativa y 30°C de temperatura. Los animales buscaron sombra durante el verano y por eso fué preciso poner en buena localización los sombreadores para tener uniformidad de pastorero del pastizal.
    • Rangeland Management in Australia

      Box, T. W.; Perry, R. A. (Society for Range Management, 1971-05-01)
      The term "rangeland" in Australia is used to designate the arid and semi-arid areas unsuitable for crop production. The lands of this pastoral zone cover about 2,200,000 square miles. This vast area accounts for 74% of the continent, yet it is occupied by only 3% of its people. Of the total area, over 99% is unimproved native rangeland, less than one-half of one percent is improved pasture, and less than one-tenth of one percent is cropped. Almost a third of the land is unoccupied. The arid rangelands carry about a third of the country's sheep and beef cattle. These livestock produce about A$400,000,000 in export income for the country. Ranges are managed on a low capital and labor input system. Many of the larger cattle properties are unfenced; livestock are controlled by water development. Areas around water and smaller properties in the arid zone may be severely deteriorated in range condition. Current research projects are designed to provide information to prevent further decline in productivity, aid development, and to improve management.
    • Range Education in East Africa

      Robertson, J. H.; Payne, G. F.; Jensen, C. V. (Society for Range Management, 1971-05-01)
      Range management instruction in East Africa is centered in the 3-year diploma course at Egerton College, Kenya. Since 1966, range diplomates have received AID Scholarships to study toward B.S. and M.S. degrees in the U.S.A. The return flow of range graduates began to replace expatriate range specialists in 1969.
    • Moisture Interception as a Factor in the Competitive Ability of Bluebunch Wheatgrass

      Ndawula-Senyimba, M. S.; Brink, V. C.; McLean, A. (Society for Range Management, 1971-05-01)
      Aerial parts of the caespitose type of bluebunch wheatgrass (Agropyron spicatum) have been shown to direct rainwater and to concentrate it in the soil immediately beneath individual plants. The degree to which water collects beneath the bunches appeared to be related to the size of the canopy. It is possible that the rapid decline of bluebunch wheatgrass under heavy grazing is related to soil moisture redistribution caused by the removal of its aerial parts.
    • Measuring Vegetation Changes on Fixed Quadrats by Vertical Ground Stereophotography

      Wells, K. F. (Society for Range Management, 1971-05-01)
      A photographic technique for recording changes in vegetation on small fixed quadrats has been modified and improved. Two 35 mm cameras fired simultaneously are used instead of one to take stereophotographs. Transparencies are viewed directly by transmitted light under a zoom stereoscope and plant cover measured by point counts made on the photographs with the aid of a counter connected to an electrically operated stage. Assessment of species composition and herbage weight is also possible from the photographs which themselves form a permanent record of vegetation on the quadrats.
    • Long-Term Grazing Effects on Fescue Grassland Soils

      Johnston, A.; Dormaar, J. F.; Smoliak, S. (Society for Range Management, 1971-05-01)
      Very heavy grazing of fescue grassland range at Stavely, Alberta, compared to light grazing, changed the color of the Ah horizon from black to dark brown and the pH from 5.7 to 6.2, reduced the percent organic matter, reduced percent total P but increased NaHCO3-soluble P, and increased soil temperature but decreased percent soil moisture. Trends indicated that soil of the very heavily grazed field was being transformed to a soil characteristic of a drier microclimate.
    • Influence of Site on Mesquite Mortality from 2,4,5-T

      Dahl, B. E.; Wadley, R. B.; George, M. R.; Talbot, J. L. (Society for Range Management, 1971-05-01)
      Soil temperature at the 18-inch depth was the most important factor affecting response of honey mesquite to 2,4,5-T application. Temperatures at this depth in the high 60's F or low 70's F resulted in no mesquite kills with the best results obtained if temperatures were over 80 F. Phenological development was essentially as important with plants having mature leaves and seed pods being easiest to kill. Trees with small and blooming spikes and those without flowers or pods were hardest to kill with 2,4,5-T. Other variables usually considered important, such as soil moisture, were important only in combination with other variables. Mesquite trees growing on upland and sandy sites are apparently more susceptible to 2,4,5-T largely because the soil is usually several degrees F warmer than bottomland and clay sites.
    • Influence of Secondary Succession on Honey Mesquite Invasion in North Texas

      Scifres, C. J.; Brock, J. H.; Hahn, R. R. (Society for Range Management, 1971-05-01)
      Quantitative vegetational relationships are reported for an exclosure protected from domestic livestock since 1941. Only 14 percent of the honey mesquite (Prosopis glandulosa Torr. var. glandulosa) stand recorded in 1941 remained in 1968. Age estimation indicated that no honey mesquite plants established after 1959. Average height of surviving honey mesquite plants was 0.5 m. Herbaceous vegetation within the exclosure is presently dominated by tobosa (Hilaria mutica (Buckl.) Benth.), buffalograss (Buchloe dactyloides (Nutt.) Englem.) and vine-mesquite (Panicum obtusum H.B.K.). An adjacent, grazed area where the honey mesquite has been removed by hand periodically during the last 27 years is dominated by annual herbs and tobosa./El estudio se llevó a cabo en la estación experimental de la Universidad de Texas A & M cerca de Spur, Texas, E.U.A. Se encontró que el número de plantas de mezquite (Prosopis glandulosa Torr. var. glandulosa), dentro de una exclusión protegida de pastoreo desde el año 1941, fué solo 14% del número original. Conforme los análisis de edad de los árboles de mezquite, no hubo plantas nuevas desde el año de 1959. Los zacates buenos aumentaron en abundancia y es posible que su competencia impidiera el establecimiento de plantas nuevas de mezquite.
    • Grass Species Growth on a Volcanic Ash-Derived Soil Cleared of Forest

      Pumphrey, F. V. (Society for Range Management, 1971-05-01)
      Grasses producing high forage yields in a 20 to 28 inch precipitation zone of northeastern Oregon on volcanic ash soil (Tolo silt loam) cleared of a stagnant forest were Greenar intermediate wheatgrass, Sherman big bluegrass, and Regar bromegrass. Tall oatgrass, meadow foxtail, and creeping meadow foxtail were high yielding when fertilized. Annually fertilizing with 60 lbs. N, 10 lbs. P, and 11 lbs. S/acre increased the mean annual forage yield 1800 lbs./acre. Fertilizing increased downy brome in species not well adapted. Fertilized forage contained a slightly lower nitrogen concentration than non-fertilized forage.
    • Evaluation of Pinyon-Juniper Conversion to Grassland

      Aro, R. S. (Society for Range Management, 1971-05-01)
      Conversion techniques applied to public lands in Colorado, Utah, Arizona, and New Mexico provided the basis for an evaluation of several methods. Burning was the most effective and the least expensive method studied. Dozing of trees into windrows, followed by seeding of grasses in the cleared areas, was the best mechanical approach examined, but requires careful site selection and economic evaluation. Chaining was the most widely used, but the least effective technique for converting pinyon-juniper woodland to grassland.
    • Evaluating Multiple Economic Effects of Forage Development and Management

      Anderson, E. W.; Jernstedt, M. L. (Society for Range Management, 1971-05-01)
      A multiple-effect approach is illustrated for evaluating the economic impact of a forage development and management project on a ranching enterprise. A nucleus project, such as an irrigated pasture, may result in a chain reaction of other potential adjustments in land use, animal husbandry, and resource management. The economic benefits illustrated are considerably greater than those usually associated with range and pasture projects because multiple effects that accrue within the total operation are considered. This is an important item for the ranch operator when making decisions on financing potential developments. Some broad guidelines are presented which are useful for evaluating economic aspects of land use, forage management and animal husbandry in conjunction with each other.
    • Emergence of Grass Seedlings Under Crop Residue Culture

      Stroh, J. R.; Sundberg, V. P. (Society for Range Management, 1971-05-01)
      Five grass species were fall seeded on dryland under three cultural treatments-summer fallow, tilled stubble, and standing stubble-in 1966, 1967, and 1968. Seedling emergence was recorded the following spring on each of the seedbeds. Significant differences in emergence were found among the grasses and the seedbeds with the summer fallow treatment generally producing more seedlings. For practical purposes of stand establishment and area occupancy, however, all cultural treatments produced adequate stands. Interactions among years, seedbeds, and grass species were too great to permit predictions of consistency for any one cultural treatment. Dramatic suppression of rhizome extension of western wheatgrass occurred under the crop residue treatments. This suppression was too severe to be attributed entirely to nitrogen deficiency. Phytotoxicity of the plant residue is suspected as a contributing factor.
    • Effects of Several Factors on Saltbush Establishment in California

      Nord, E. C.; Hartless, P. F.; Nettleton, W. D. (Society for Range Management, 1971-05-01)
      Certain saltbush taxa can be established by direct seeding and may reduce fire hazards on fuel-breaks in California chaparral areas. Fourwing, allscale, and Gardner saltbushes were seeded at depths of 1/2 and 1 inch on four spring dates 2 to 4 weeks apart on noncalcareous soils at two test sites. A planting depth of 1/2 inch gave better results than 1 inch, and late spring when mean soil temperatures range between 60 and 65 F is apparently the best time for seeding if moisture is adequate. Fourwing saltbush produced the best stands and largest plants. The saltbush species and strains from sources closer to the planting site, or similar to it, or have the widest distributional range and tolerance to soil salts are most likely to be established by direct seeding and grow satisfactorily on neutral to slightly acid soil.
    • Effect of Spraying with 2,4-D upon Abundance of Pocket Gophers in Franklin Basin, Idaho

      Hull, A. C. (Society for Range Management, 1971-05-01)
      Four 50 × 50 foot plots were sprayed with 2 lb./acre 2,4-D in 1959, 1960, 1965 and 1969 to kill fleshy-rooted, spring-growing plants and annuals. These plants are the major source of food for pocket gophers. Averaging the 10-year period, 1960-69, spraying reduced gopher mounds by 93% and winter casts by 94% when compared to the unsprayed areas.
    • An Evaluation of a Interseeded Sideoats Grama Stand Four Years after Establishment

      Willard, E. E.; Schuster, J. L. (Society for Range Management, 1971-05-01)
      Sideoats grama can be successfully interseeded into abandoned cropland on the High Plains of Texas. The use of fertilizer and alfalfa with planting did not increase the stand, plant size, or production of sideoats grama. It is concluded that interseeding can increase total forage production but the inclusion of fertilizer and alfalfa in this particular study was an added expense that could not be justified. Livestock showed a definite preference for the forage on the interseeded areas over that on the non-seeded areas. Species utilization by cattle was found to be highest for kochia, followed by silver bluestem, sideoats grama, western wheatgrass, sand dropseed, red threeawn and tumble windmillgrass.
    • Acidifying Nitrogen Compounds and Range Fertilization

      Owensby, C. E.; Launchbaugh, J. L. (Society for Range Management, 1971-05-01)
      Soil pH changes on plots fertilized with ammonium-containing compounds indicated possible detrimental effects on range plant communities. The mechanism for the pH change and possible solution for correction of the problem are discussed.