• Variation in Pinehill Bluestem, a Southern Ecotype of the Andropogon scoparius Complex

      Grelen, H. E. (Society for Range Management, 1974-07-01)
      Pinehill bluestem is the most common variant of the little bluestem (Andropogon scoparius) complex in pine forests of north and central Louisiana and east Texas. It is also frequent in adjacent portions of Oklahoma and Arkansas. It differs from other inland forms of little bluestem primarily in its unreduced pedicellate spikelets, which are equal in size to the sessile spikelets. Because of vegetative similarity between pinehill bluestem and associated forms of A. scoparius, separation of varieties for purposes of forage management is not recommended.
    • Tolerance of Bermudagrass to Herbicides

      Bovey, R. W.; Meyer, R. E.; Holt, E. C. (Society for Range Management, 1974-07-01)
      Herbicides 2,4-D, 2,4,5-T and dicamba applied in spring or fall usually did not reduce yields of bermudagrass. When applied during dry periods, picloram reduced density and yield of bermudagrass. Degree of bermudagrass injury was directly related to rate of herbicide. "Common," "Coastal," and "Coastcross-1" varieties responded similarly to each herbicide studied. Kleingrass, a new forage grass growing in the plot area, was tolerant of all herbicide treatments, including picloram.
    • Seedling Emergence and Survival from Different Seasons and Rates of Seeding Mountain Rangelands

      Hull, A. C. (Society for Range Management, 1974-07-01)
      At a mountain rangeland site in southeastern Idaho, a mixture of five grasses was drilled at 10 and 25 lb/acre at six seasons each year for 4 years. The 25-lb rate produced significantly more seedlings than the 10-lb rate, but 10 lb was slightly more efficient in producing seedlings. Seedling survival was best from seeding in June, followed closely by July 1 and then November 1, October 1, September 1, and August 1. As an average of both seeding rates, per 100 seeds of the mixture planted in June, 12 plants emerged, five were alive at the end of 1 year, and two at the end of 3 years. At each planting time, intermediate wheatgrass seed was placed between nylon strips in the soil to determine the fate of the seeds. For 100 seeds of intermediate wheatgrass in nylon strips in June, 84 germinated, 30 plants emerged, and 12 were alive at the end of 1 year.
    • Salt and Oxalic Acid Content of Leaves of the Saltbush Atriplex halimus in the Northern Negev

      Ellern, S. J.; Samish, Y. B.; Lachover, D. (Society for Range Management, 1974-07-01)
      Saltbush (Atriplex halimus L.) in the semiarid south of Israel was analyzed for leaf sodium, chlorine, and oxalic acid in order to identify and propagate low-salt bushes likely to be browsed more readily by range cattle and sheep. No correlation was found between leaf chlorine and growth habit factors like bush size and leafiness, or between chlorine and sodium. High-chlorine bushes had a lower Na/Cl ratio, and probably a substantial proportion of the Na+ and Cl- ions are not linked as NaCl. Leaf oxalic acid was lower in high-chlorine bushes. The data suggest that moisture streess sharply reduced insoluble leaf oxalate. Values found are unlikely to cause toxicity problems in livestock.
    • Relationships of Taste, Smell, Sight, and Touch to Forage Selection

      Krueger, W. C.; Laycock, W. A.; Price, D. A. (Society for Range Management, 1974-07-01)
      Chemical impairment of taste, smell, and touch and physical obstruction of sight were studied in relation to forage preferences of sheep in a tall-forb plant community. Taste was the special sense most influential in directing forage preference; the other senses appeared to supplement taste. Sheep preferred sour and sweet plants and generally rejected bitter plants, although some were palatable. Smell was of minor importance in selection. Touch and sight related to such specific plant conditions as succulence and growth form. Simultaneous impairment of all four senses did not result in completely random selection, but did increase preference for unpalatable plants and decrease preference for palatable ones.
    • Relationship between Precipitation and Annual Rangeland Herb Age Production in Southeastern Kansas

      Shiflet, T. N.; Dietz, H. E. (Society for Range Management, 1974-07-01)
      Herbage production on the loamy upland range site in southeastern Kansas is related to seasonal precipitation. April through September precipitation gave the most reliable predictor of total herbage production. However, this value cannot be determined early enough in the season to make adjustments in livestock numbers on seasonally grazed ranges. May through July precipitation, though less precise than that for April through September, can also be used to predict herbage yields and is timely enough for seasonal adjustments in livestock. Big bluestem was the only major species that showed significant correlation with seasonal precipitation. May through July precipitation was the best predictor of the herbage produced by this species.
    • Influence of Nitrogen and Irrigation on Carbohydrate Reserves of Buffalograss

      Pettit, R. D.; Fagan, R. E. (Society for Range Management, 1974-07-01)
      Five rates (0, 30, 60, 90, and 120 kg of N/ha) of nitrogen fertilizer were applied in April, 1971, to a deep hardland range site where buffalograss (Buchloe dactyloides Nutt.) predominated. The influence of these nitrogen applications on the carbohydrate reserve (TAC) concentration of irrigated and nonirrigated buffalograss roots and crowns was evaluated. In 1971 the TAC reserve concentration of the storage tissues varied inversely with rate of nitrogen application until the past ripe phenological stage. After this date, TAC's accumulated more rapidly in the heavier N treatments. In 1972, insignificantly more TAC were found in the control and 30 kg N/ha treatments at the hard seed stage. On all sampling dates buffalograss crowns contained more reserve carbohydrates than did the roots. Similarly, stolons contained 19% more TAC than did the crowns. Water applications reduced the carbohydrate reserves of this grass from 15 to 36%. Irrigation increased female spikelet yield by 44 kg/ha while stolon yield was similar regardless of water regime.
    • Infiltration for Three Rangeland Soil-Vegetation Complexes

      Tromble, J. M.; Renard, K. G.; Thatcher, A. P. (Society for Range Management, 1974-07-01)
      A rotating disk rainfall simulator was used to examine infiltration-runoff relations from selected rangeland sites as influenced by a soil-vegetation complex. The simulator assisted in quantifying infiltration rates for different management practices on different soil types. Infiltration was greater for brush dominated plots than for either grazed plots or grass plots without grazing. Antecedent soil moisture decreased infiltration rates. Crown cover was approximately twice as much on brush plots as on grass plots and significantly influenced infiltration.
    • Grazing Management Terminology

      Kothmann, M. M. (Society for Range Management, 1974-07-01)
    • Future of Rangelands in the United States

      Long, R. W. (Society for Range Management, 1974-07-01)
    • Future of Rangelands in Canada

      Whelan, E. F. (Society for Range Management, 1974-07-01)
    • Evaluation of the Atrazine-Fallow Technique for Weed Control and Seedling Establishment

      Eckert, R. E.; Asher, J. E.; Christensen, M. D.; Evans, R. A. (Society for Range Management, 1974-07-01)
      The atrazine-fallow technique was evaluated for 3 years on study areas of from 50 to 1,000 acres. Atrazine at 0.6 to 1.2 lb/acre was applied in the fall by ground rig, by fixed-wing aircraft, or by helicopter. Ground-rig application gave the most uniform control of cheatgrass and tumble mustard during the fallow year. Air application usually left weedy strips between swaths of excellent weed control. Wheatgrasses and other species of grasses and forbs were fall-seeded with the standard and deep-furrow rangeland drills 1 year after herbicide application. Fair to excellent seedling stands were obtained in all years. However, in 1 year a valid evaluation of treatment effects was not possible because of depradation and unusually high spring precipitation in the seedling year. In 2 years, environmental conditions were near normal, and depredation was reduced by use of large study areas and insect control. Under these conditions, good established stands of crested, intermediate, pubescent, and Siberian wheatgrasses were obtained by the chemical-fallow technique.
    • Evaluation of Methods for Screening Grasses for Resistance to Grasshopper Feeding

      Hewitt, G. B.; Blickenstaff, C. C. (Society for Range Management, 1974-07-01)
      A study was initiated to find a rapid method of screening forage plant selections for grasshopper preference. Six grass species both as seedlings and as plants 6 weeks older were fed to nymphs and/or adults of five grasshopper species and one group of nymphs of mixed species. It was concluded that it is feasible to screen plant species in the seedling stage for preference by using grasshopper nymphs because the nymphs selected plant species of both ages equally well and their preferences were similar to those of adults. This allows for more rapid screening of plants than would be the case with older plants and adult grasshoppers.
    • Effect of Planting Depth on Seedling Growth of Russian Wildrye (Elymus junceus Fisch.)

      McGinnies, W. J. (Society for Range Management, 1974-07-01)
      Planting depth of Russian wildrye (Elymus junceus Fisch.) influenced seedling growth during the seedling year. In field plantings over 4 years at two locations, plants from 2.5- and 3.8-cm planting depths were significantly taller than plants from the 1.3-cm depth. In greenhouse plantings, plants from 3.8-cm planting depth were consistently taller than plants from the 1.3-cm depth, but the plants from the 1.3-cm depth generally produced more tillers. Transplants with crowns set 1.3 cm deep produced more tillers than those with crowns set 3.8 cm deep. Depth of transplanting had no effect on height of plants. The height difference between plants planted at different depths apparently resulted from some form of seedling selection at greater depths, but the number of tillers probably was determined by crown depth alone. Grass breeders using planting depth to evaluate seedling vigor may be inadvertently selecting for taller plants. Weight per plant tended to be higher for the 1.3-cm planting depth than for the 3.8-cm depth, but this effect was not consistent.
    • Control of Gambel Oak with Three Herbicides

      Van Epps, G. A. (Society for Range Management, 1974-07-01)
      Fenuron, picloram, and 3 phenoxy compounds were applied to Gambel oak (Quercus gambellii Nutt.) to attain a complete kill of the plant. Spring treatments of fenuron applied to the soil at rates of 8 lb ae/acre or higher were effective as were fall applications. Picloram as a soil treatment was not effective. Foliar spraying with picloram and the phenoxy compounds at the higher rates killed oak crowns but not the plants. The herbicides varied in their injury to under-story vegetation.
    • Comparison of Vegetation Structure and Composition in Modified and Natural Chaparral

      Rosario, J. A.; Lathrop, E. W. (Society for Range Management, 1974-07-01)
      Six years following type conversion of a chaparral plot in southern California, density per acre and number of shrub species were reduced by 79.7% and 40%, respectively. Replanting following brush removal resulted in establishment of a perennial bunchgrass community with a basal area of 7% as compared to essentially no grass on the control plot.
    • Clipping Height and Frequency Influence Growth Response of Nitrogen-Fertilized Blue Grama

      Bekele, E.; Pieper, R. D.; Dwyer, D. D. (Society for Range Management, 1974-07-01)
      A greenhouse study with two clipping heights (1- and 2-inch stubble heights) and two clipping frequencies (every 10 and 20 days) showed that blue grama was able to make use of nitrogen fertilizer much more efficiently when unclipped than when clipped. Both clipping heights and clipping intervals decreased shoot and root weights on fertilized plants compared to fertilized and unclipped plants. The effect of clipping on unfertilized plants was much less drastic than on fertilized plants.
    • Carbohydrate and Organic Nitrogen Concentrations within Range Grass Parts at Maturity

      Perry, L. J.; Moser, L. E. (Society for Range Management, 1974-07-01)
      Total nonstructural carbohydrate (TNC) levels were significantly different among eight range grasses at maturity. Roots, rhizomes, and stem bases (storage organs), differed significantly in percentage TNC within rhizomatous and bunch-type (non-rhizomatous) grasses. Percent organic nitrogen differed significantly among grasses and storage organs but not to the same extent as occurred with TNC. We suggest that TNC concentrations of storage organs must be determined for each grass before sampling for TNC levels, in order to locate storage organs with greatest TNC concentration.
    • Canopy Structure of a Tall-grass Prairie

      Conant, S.; Risser, P. G. (Society for Range Management, 1974-07-01)
      Several characteristics of vegetation structure, including height, basal cover, cover repetition, leaf area, and distribution of aboveground biomass, were examined in grazed and ungrazed treatments of native Oklahoma tall-grass prairie. Selected structural parameters were evaluated to determine their value as reliable predictors of biomass dynamics. Cover repetition and leaf area showed good correlation with above-ground biomass. Studies of vegetation structure may provide an additional basis for understanding grazing response in grassland communities, and may serve as a basic tool for clarifying the roles of water, light and nutrients, and their effects on grassland production.