• Production Potential of Four Winter Annual Grasses

      Robocker, W. C. (Society for Range Management, 1973-01-01)
      Forage production of downy brome, rattlesnake chess, Japanese brome, and medusahead were compared in a nursery trial on an individual plant basis. Downy brome and Japanese brome produced significantly more forage than did rattlesnake chess or medusahead. The difference in production adds justification for selective control of medusahead in downy brome with diuron.
    • Production Response of Native and Introduced Grasses to Mechanical Brush Manipulation, Seeding, and Fertilization

      Gonzalez, C. L.; Dodd, J. D. (Society for Range Management, 1979-07-01)
      Effects of two mechanical brush manipulation treatments (root-plowing and front-end stacking) with and without grass seeding and with and without nitrogen fertilization on herbaceous forage production were investigated in the Rio Grande Plain of Texas. Total herbaceous production (4-year average) was 5,981 for root-plowing and 4,789 kg/ha for front-end stacking as compared with 2,178 kg/ha for the undisturbed control. The 4-year average yield of buffelgrass (Cenchrus ciliaris L. (L.) Link) seeded alone contributed 53% of total herbaceous production on plots with root-plowing, 73% on plots with front-end stacking, and 38% on control plots. The combined yield of three native species, pink pappus-grass (Pappophorum bicolor Fourn.), four-flower trichloris (Trichloris pluriflora Fourn.), and Arizona cottontop (Digitaria californica (Benth) Henr.), seeded as a mixture contributed 41% of the total herbaceous production on plots with rootplowing, 28% on plots with front-end stacking, and 11% on control plots. The application of 45 kg/ha nitrogen significantly increased total herbaceous production the season after application.
    • Productivity Dynamics of a Native Temperate Grassland in Argentina

      Sala, O.; Deregibus, V. A.; Schlichter, T.; Alippe, H. (Society for Range Management, 1981-01-01)
      Studies of aerial net primary productivity (ANPP) were made on a grassland that had been excluded from livestock grazing for four years. ANPP was calculated by summation of individual species and corrections based on fluctuations of standing dead litter. The grassland produced a minimum of 4 kg of dry material ha-1 d-1 in the fall and a maximum of 30 kg of dry materia ha-1 d-1 during the spring.
    • Productivity of a Soil Biosequence of the Fescue Prairie-Aspen Transition

      Lutwick, L. E.; Dormaar, J. F. (Society for Range Management, 1968-01-01)
      Grassland soils have some quality that enables plants to respond to P fertilizer. This quality deteriorates when poplar trees advance on rangelands; it is completely destroyed when coniferous trees become the dominant vegetation. Clearing of trees and seeding of grass returns some grassland character to soil. If soil organic P is considered an index, NP fertilizers along with the grass are expected to hasten the return of the grassland character.
    • Productivity of Cenchrus ciliaris in relation to rain-fall and fertilization

      Rao, A. S.; Singh, K. C.; Wight, J. R. (Society for Range Management, 1996-03-01)
      Forage for livestock is always in short supply in the arid zone of India. Cenchrus ciliaris L. is one of the major forage grasses cultivated in this region. We studied its productivity in relation to rainfall and nitrogen (N) and phosphorus (P) fertilization in the Indian arid zone at Jodhpur during 1983 to 1992. Factorial combinations of 4 rates of N (0, 20, 40, and 60 kg ha-1) and 3 rates of P (0, 15, and 30 kg ha-1) were applied annually. Twenty kg N ha-1 was the most effective fertilizer treatment, increasing average annual forage yields from 942 to 1,785 kg ha-1 over the 10 year study with significant yield increases occurring in 7 of the 10 years. Yield responses to N rates greater than 20 kg ha-1 occurred only during the last 3 years of the study and then only at the 60 kg ha-1 rate with either 15 or 30 kg P ha-1. Yields reached maximum levels on both the nonfertilized and fertilized plots with between 180 and 250 mm of growing-season rainfall.
    • Productivity of Irrigated Tropical Grasses under Different Clipping Frequencies in the Semidesert Region of The Sudan

      Osman, A. E. (Society for Range Management, 1979-05-01)
      On irrigated pastures, buffel grass, rhodes grass, bambatsi panicgrass, and green panicgrass were generally more productive than para grass, blue panic, and switchgrass. Clipping at 4- and 6-week intervals during the summer resulted in greater total annual yield than clipping at 2-week intervals. However, percent crude protein in grasses clipped at 2-week intervals was double that in grasses clipped at 6-week intervals. Swtichgrass, para grass, and blue panic appeared least able to withstand clipping over the 2-year period of the study. The results suggested that buffel grass, green panic, bambatsi panic, and rhodes grass, harvested at 4-week intervals would be the best choice for production of nutritious forage on irrigated pastures in the semiarid region of the Sudan.
    • Productivity of long-term grazing treatments in response to seasonal precipitation

      Milchunas, D. G.; Forwood, J. R.; Lauenroth, W. K. (Society for Range Management, 1994-03-01)
      Estimates of forage production for long-term ungrazed, lightly, moderately, and heavily grazed treatments (0, 20, 40, 60% removal of annual forage production) established in 1939 in shortgrass steppe communities were subjected to multiple regression analyses to assess long-term temporal trends resulting from grazing and short-term sensitivities to abiotic factors. Average production based upon all data from 1939-1990 was 75, 71, 68, and 57 g m-2 yr-1 for ungrazed, lightly, moderately, and heavily grazed treatments, respectively. Variability in forage production was explained mostly by cool-season precipitation, and magnitude of forage production was more sensitive to annual fluctuations in precipitation than to long-term grazing treatments. Production per unit increase of precipitation was greater for cool-season than warm-season precipitation, but only when cool-season precipitation was above average. This was attributed to differences in evaporative demand of the atmosphere resulting in different utilization-efficiencies of small and large rainfall events in the 2 seasons. Based upon a regression model constructed using data from 1939 through 1962, forage production was not affected by grazing to 20 to 35% removal. For pastures of average relative productivity, grazing at 60% level of consumption for 25 years resulted in a 3% decrease in forage production in wet years and a 12% decrease in dry years. Estimates of productivity after 50 years of heavy compared to light grazing treatment were -5 and -18% for wet and average y precipitation, respectively.
    • Productivity of Russian Wildrye and Crested Wheatgrass and Their Effect on Prairie Soils

      Smoliak, S.; Dormaar, J. F. (Society for Range Management, 1985-09-01)
      Crested wheatgrass (Agropyron cristatum (L.) Gaertn.) and Russian wildrye (Elymus junceus Fisch.) are used extensively as seeded pastures in the Prairie Provinces of Canada. Rangeland plowed in 1954 was planted to the 2 grasses in 1955. Herbage was harvested over a 25-year period, root weights were determined in 1977, and soil samples were obtained in 1965 and 1978 from the 2 seeded pastures and from adjacent native rangeland from each of 3 replicates. Forage production from the seeded pastures was greatest 4 years after seeding. Averaged over all years, crested wheatgrass yielded 113% more and Russian wildrye yielded 47% more forage than did native rangeland. Total root weight in the surface 15-cm layer of soil was greater on the native rangeland pasture than on the seeded pastures. Soils from native range pastures generally contained more organic carbon, less sodium, and had lower pH and sodium adsorption ratios than the soils from Russian wildrye pastures seeded 10 and 23 years before the soils were sampled. The organic C and pH's of the soils obtained from crested wheatgrass pastures decreased during the 23-year period while those of soils from the native range did not change.
    • Productivity of Tall Wheatgrass and Great Basin Wildrye under Irrigation on a Greasewood-Rabbitbrush Range Site

      Eckert, R. E.; Bruner, A. D.; Klomp, G. J. (Society for Range Management, 1973-07-01)
      Nonbeneficial phreatophytes, greasewood and rubber rabbitbrush, in the Humboldt River Basin annually waste approximately 103,000 acre feet of water that could be used beneficially if forage species were established. After brushbeating, tall wheatgrass and Great Basin wildrye were spring seeded and established by sprinkler irrigation. Irrigation was continued for 3 to 5 years to induce root penetration into a capillary fringe so that grasses would persist as beneficial phreatophytes. After irrigation ceased, productivity of 115 to 710 lb/acre indicated that roots had not reached the capillary fringe and that continued irrigation was necessary to maintain production. Soil physical characteristics restricted root growth, and productivity with limited water or without water was reduced by chemical properties of a saline-sodic soil. Highest production of tall wheatgrass (4000 to 6000 lb/acre) and Great Basin wildrye (2400 to 2600 lb/acre) was obtained 3 years after seeding with weekly irrigations of 1.25 inches.
    • Productivity, Respiration, and Light-Response Parameters of World Grassland and Agroecosystems Derived From Flux-Tower Measurements

      Gilmanov, Tagir G.; Airess, L.; Barcza, Z.; Baron, V. S.; Belelli, L.; Beringer, J.; Billesbach, D.; Bonal, D.; Bradford, J.; Ceschia, E.; et al. (Society for Range Management, 2010-01-01)
      Grasslands and agroecosystems occupy one-third of the terrestrial area, but their contribution to the global carbon cycle remains uncertain. We used a set of 316 site-years of CO2 exchange measurements to quantify gross primary productivity, respiration, and light-response parameters of grasslands, shrublands/savanna, wetlands, and cropland ecosystems worldwide. We analyzed data from 72 global flux-tower sites partitioned into gross photosynthesis and ecosystem respiration with the use of the light-response method (Gilmanov, T. G., D. A. Johnson, and N. Z. Saliendra. 2003. Growing season CO2 fluxes in a sagebrush-steppe ecosystem in Idaho: Bowen ratio/energy balance measurements and modeling. Basic and Applied Ecology 4:167-183) from the RANGEFLUX and WORLDGRASSAGRIFLUX data sets supplemented by 46 sites from the FLUXNET La Thuile data set partitioned with the use of the temperature-response method (Reichstein, M., E. Falge, D. Baldocchi, D. Papale, R. Valentini, M. Aubinet, P. Berbigier, C. Bernhofer, N. Buchmann, M. Falk, T. Gilmanov, A. Granier, T. Grünwald, K. Havránková, D. Janous, A. Knohl, T. Laurela, A. Lohila, D. Loustau, G. Matteucci, T. Meyers, F. Miglietta, J. M. Ourcival, D. Perrin, J. Pumpanen, S. Rambal, E. Rotenberg, M. Sanz, J. Tenhunen, G. Seufert, F. Vaccari, T. Vesala, and D. Yakir. 2005. On the separation of net ecosystem exchange into assimilation and ecosystem respiration: review and improved algorithm. Global Change Biology 11:1424-1439). Maximum values of the quantum yield (a = 75 mmol mol-1), photosynthetic capacity (Amax = 3.4 mg CO2 m-2 s-1), gross photosynthesis (Pg, max = 116 g CO2 m-2 d-1), and ecological light-use efficiency (eecol = 59 mmol mol-1) of managed grasslands and high-production croplands exceeded those of most forest ecosystems, indicating the potential of nonforest ecosystems for uptake of atmospheric CO2. Maximum values of gross primary production (8 600 g CO2 m-2 yr-1), total ecosystem respiration (7 900 g CO2 m-2 yr-1), and net CO2 exchange (2 400 g CO2 m-2 yr-1) were observed for intensively managed grasslands and high-yield crops, and are comparable to or higher than those for forest ecosystems, excluding some tropical forests. On average, 80% of the nonforest sites were apparent sinks for atmospheric CO2, with mean net uptake of 700 g CO2 m-2 yr-1 for intensive grasslands and 933 g CO2 m-2 d-1 for croplands. However, part of these apparent sinks is accumulated in crops and forage, which are carbon pools that are harvested, transported, and decomposed off site. Therefore, although agricultural fields may be predominantly sinks for atmospheric CO2, this does not imply that they are necessarily increasing their carbon stock. 
    • Profitability and Flexibility of Two Range Cattle Systems in the Rolling Plains of Texas

      Boykin, C. C. (Society for Range Management, 1967-11-01)
      Adjusting cattle inventories to changes in range forage supply is a major problem in ranching. A costs and income analysis of a cow-calf system and of a cow-yearling system over a 10-year period of changing prices and range forage supplies revealed little difference in relative profitability between the two systems when additional replacements were purchased in response to increases in range forage supply. When additional replacements were raised, the cow-yearling system proved to be more profitable and more flexible than the cow-calf system. In shifting to a cow-yearling system, breeding cow numbers must be reduced in proportion to the increase in yearlings if overgrazing is to be avoided.
    • Profitability of Carbon Sequestration in Western Rangelands of the United States

      Ritten, John P.; Bastian, Christopher T.; Rashford, Benjamin S. (Society for Range Management, 2012-07-01)
      Concerns over climate change have increased interest in carbon sequestration in agricultural lands. While the per-hectare carbon capture potential of rangelands is less than either cropland or forests, existing research suggests modest changes in carbon storage on rangelands can potentially alter the global carbon cycle. This paper examines the potential firm-level revenues from voluntary carbon offset programs, such as the Chicago Climate Exchange (CCX) Rangeland Soil Carbon Offset program. We estimate revenues for short-term voluntary offsets given historical prices and prices projected with potential cap-and-trade legislation. We also estimate revenues assuming 100-yr offsets are required to meet international sequestration standards. Simulation results indicate a relatively wide range of modest revenues from recent CCX contracts and carbon prices. The analysis suggests that recent carbon prices or low-end projected prices from cap-and-trade legislation are not likely to encourage producer participation. Medium and high carbon price projections for cap-and-trade legislation may make carbon sequestration a more attractive option for rangeland managers, but given potential requirements for projects to meet international guidelines for greenhouse gas offset projects, many issues remain before range managers may be interested in carbon sequestration as an enterprise./La preocupación sobre el cambio climático ha aumentado el interés en el secuestro de carbono en tierras de uso agropecuario. Mientras que el potencial de captura de carbono en pastizales es menor que en tierras agrícolas y bosques, investigaciones sugieren que cambios modestos en el almacén de carbono en pastizales potencialmente alteran el ciclo global del carbono. Este artículo examina el ingreso potencial a nivel de empresa en programas voluntarios para la compensación de carbono tales como el programa de Compensación de Carbono en Pastizales del Chicago Climate Exchange (CCX). Estimamos ingresos en el cortoplazo por compensaciones voluntarias dado precios históricos y precios proyectados con potencial con legislación de tope y compra-venta. También estimamos ingresos asumiendo 100 años de compensación tal como es requerido para cumplir los estándares internacionales de captura. Resultados de simulaciones indican relativamente amplio margen de modestos ingresos de contratos recientes del CCX y precios del carbono. El análisis sugiere que los precios recientes del carbono o proyectos demenor importancia de la legislación tipo tope y compra-venta no tienen posibilidad de encontrar la participación de los productores. La proyección de precios medianos y altos del carbono de la legislación tope y compra-venta podría hacer más atractiva la opción de captura de carbono para los manejadores de pastizales pero, dado los requerimientos potenciales para proyectos que cumplan con los lineamientos internacionales para la compensación de proyectos de gases de efecto invernadero, muchos aspectos están presentes antes de que los manejadores de pastizales pudieran estar interesados en el secuestro de carbono a nivel empresarial.
    • Profitable Ranching During Drought

      Royal, J. (Society for Range Management, 1957-11-01)
    • Profitable Use of Fertilizer on Native Meadows

      Nelson, M.; Castle, E. N. (Society for Range Management, 1958-03-01)
    • Progress through Performance Records

      Cox, Don (Society for Range Management, 1965-09-01)
      A rancher's version of range beef-cattle performance testing in Nebraska-history, accomplishments, and problems.
    • Proline Concentrations in Water Stressed Grasses

      Bokhari, U. G.; Trent, J. D. (Society for Range Management, 1985-01-01)
      This study was conducted to screen several warm- and cool-season grasses for their proline-accumulating ability under water stressed conditions in the growth chamber. Plants of Old World bluestems (Bothriochloa spp.), tall fescue (Festuca arundinacea), western wheatgrass (Agropyron smithii) and weeping lovegrass (Eragrostis curvula) were subjected to water stress conditions at the vegetative stage. Water stressed plants exhibited a significantly greater (P<.05) increase in proline concentration than the non-stressed and the stress relieved plants. There was also a significant difference (P<.01) in the proline-accumulating ability of various species. An interdependency was observed between leaf water potential and proline concentration in all the species under water-stressed conditions.
    • Pronghorn Reactions to Winter Sheep Grazing, Plant Communities, and Topography in the Great Basin

      Clary, W. P.; Beale, D. M. (Society for Range Management, 1983-11-01)
      The winter distribution of pronghorn over a 142-km2 area on the Desert Experimental Range was significantly related to sheep grazing during the current winter, presence of black sagebrush, and topographic characteristics. Even moderate sheep use during the dormant period left grazing units relatively unfavorable for pronghorn until spring regrowth-at least on ranges where key pronghorn forage plants were in short supply. Winter use areas preferred by pronghorn were above the valley bottoms in rolling to broken topography where black sagebrush communities were evident. Movement characteristics of pronghorn have allowed many of them to readily locate rested grazing units, and, therefore, avoid severe dietary competition with sheep.
    • Propagation of Nevada Shrubs by Stem Cuttings

      Everett, R. L.; Meeuwig, R. O.; Robertson, J. H. (Society for Range Management, 1978-11-01)
      Stem cuttings of 54 Nevada shrub species varied in rooting capacity. Among those species most easily propagated were Artemisia spinescens, Atriplex lentiformis, Ceratoides lanatu, Grayia spinosa, Lepidospartum latisquamum, Prunus andersonii, Rosa woodsii, Salvia dorrii, and Vitis arizonica. Semihardwood cuttings were superior to either softwood or hardwood cuttings in rooting success. Differences in rooting potential among cuttings of the same species taken from different sites were also apparent.
    • Propane-powered Low-volume Sprayer and Weed Burner

      Jensen, E. H.; Robocker, W. C. (Society for Range Management, 1955-01-01)
    • Proper Burning Intervals for Tobosagrass in West Texas Based on Nitrogen Dynamics

      Sharrow, S. H.; Wright, H. A. (Society for Range Management, 1977-09-01)
      The time required for re-establishment of pre-fire nitrogen levels in tobosagrass (Hilaria mutica) communities in the Rolling Plains of West Texas was studied on five different ages of burns over a 2-year period. Time elapsed after burns varied from one to five growing seasons for both convex and concave topographic sites near Colorado City, Texas. Standing old growth-N returned to pre-fire levels by the end of the third growing season. However, litter-N on the soil surface took 5 years to reach pre-fire levels on concave sites and an estimated 8 years on convex sites. High variation prevented the recognition of any meaningful trends in root or soil nitrogen levels. Based on this data, tobosagrass should not be burned more frequently than 5 to 8 years, depending on the site.