• Blacktail Prairie Dogs, Desert Cottontails and Cattle Trophic Relations on Shortgrass Range

      Hansen, R. M.; Gold, I. K. (Society for Range Management, 1977-05-01)
      The trophic relations among blacktail prairie dogs, desert cottontails, and cattle were determined among three dogtowns at the Central Plains Experimental Range near Nunn, Colo. Sedges were the most important food of prairie dogs and cottontails and the second most important food of cattle on an annual basis. There was a high percentage similarity in the diets of the three herbivores studied; and they consumed large percentages of sedges and grass. The amount of aboveground herbage eaten and made unavailable because of soil disturbances by prairie dogs and cottontails was about 24% of the total potential annual production.
    • Cane Bluestems: Forage Yield, Forage Quality, and Water-Use Efficiency

      Koshi, P. T.; Eck, H. V.; Stubbendieck, J.; McCully, W. G. (Society for Range Management, 1977-05-01)
      Three collections of cane bluestem (Bothriochloa barbinodis Herter) were evaluated under three water and three harvest regimes. Dry matter yields, under natural rainfall and irrigation, averaged 3.8 and 8.7 metric tons/ha, respectively. Productivity of the three collections ranked G-866 > G-820 > PMT-333 under natural rainfall, but with irrigation, the ranking was G-820 > G-866 > PMT-333. One and two harvests per season resulted in near-equal yields, but three harvests decreased yields. Cane-bluestem forage contained about 10% protein and 0.22% phosphorus (P) in mid-June. In November, previously unclipped forage contained 4.4% protein and 0.12% P, while that clipped twice contained 7.3% protein and 0.18% P. Yield and quality of cane bluestem compared favorably with that of switchgrass (Panicum virgatum L.) grown in a similar study. Maximum production was obtained with about 77 cm of water use (rainfall + irrigation + soil water).
    • Comparison of Soil Water Used by a Sagebrush-Bunchgrass and a Cheatgrass Community

      Cline, J. F.; Uresk, D. W.; Rickard, W. H. (Society for Range Management, 1977-05-01)
      Two contrasting plant communities occur on the Arid Lands Ecology (ALE) Reserve in south-central Washington, one dominated by a mixture of sagebrush and bluebunch wheatgrass and the other by a nearly pure stand of cheatgrass. At the beginning of the spring growing season in 1974, a year of above-average precipitation, both communities had about the same amount of soil water stored in the first 18 dm of the soil profile. During the growing season, the quantity of soil water used by the sagebrush-bunchgrass and cheatgrass communities was 15 and 8 cm, respectively. The difference in soil water used by the two communities is attributed to a deeper root system and a longer growing period by plants of the sagebrush-bunchgrass community.
    • Competition Between Russian Wildrye Seedlings and Four Common Weeds

      Drawe, D. L.; Palmblad, I. G. (Society for Range Management, 1977-05-01)
      Russian wildrye was tested in the greenhouse for both interspecific and intraspecific competition using various densities of Russian wildrye, alone and in combination with cheatgrass, peppergrass, Russian thistle, and halogeton. With Russian wildrye alone, production and vigor first increased as plant density increased, then decreased at the highest density tested. Under interspecific competition, both survival and production were reduced at all weed densities tested. Combinations of species were more adverse to vigor and production of Russian wildrye than were single species of weeds.
    • Composition and Degradation of Jackrabbit and Cottontail Fecal Pellets, Texas High Plains

      Flinders, J. T.; Crawford, J. A. (Society for Range Management, 1977-05-01)
      Fecal pellets were taken from black-tailed jackrabbits and desert cottontail rabbits for studies of rates of natural degradation. Microscopic analyses of fecal samples showed a significant difference in the proportion of grasses, forbs, and woody plants ingested by the two leporid species sampled. Jackrabbits had ingested greater proportions of grasses and woody plants while cottontails had ingested greater proportions of forb material. Degradation of fecal pellets was observed at regular intervals from 1972 to 1974. Time required for complete disappearance of pellets was estimated at 4.4 years for jackrabbits and 9.5 years for cottontails. Relative humidity and precipitation were strongly correlated (r = -0.98 and -0.95 for jackrabbits and cottontails, respectively) with disappearance of pellets.
    • Early Growth of Nordan Crested Wheatgrass and Sherman Big Bluegrass

      Rittenhouse, L. R.; Sneva, F. A. (Society for Range Management, 1977-05-01)
      Early growth of Sherman big bluegrass was compared with that of Nordan crested wheatgrass in central Oregon. Growth curves of the two grasses were similar between April 5 and May 15, as measured by increase in oven-dry production. Both species produced similarly during the 6-year study, except that, in 1969 big bluegrass yields were higher on May 15.
    • Economic Evaluation of Cattle and White-tailed Deer Response to Aerial Spraying of Mixed Brush

      Whitson, R. E.; Beasom, S. L.; Scifres, C. J. (Society for Range Management, 1977-05-01)
      The combined economic effects, based on returns for lease hunting of white-tailed deer in conjunction with lifestock production, were calculated following partial treatment (80% sprayed in alternating strips) and complete treatment of mixed brush in South Texas with aerial sprays of 2,4,5-T and picloram at 1 lb/acre. Both approaches were economically feasible based on a 10% discount rate over a 9-year projected treatment life, except when the brush was completely sprayed and cattle prices were $0.255/lb. However, when cattle prices were less than $0.495/lb, partial treatment by aerial spraying was preferred, in an economic sense, since returns from lease hunting where 20% of the brush was left untreated for wildlife habitat more than compensated for reduced cattle returns.
    • Estimating Overwinter Bitterbrush Utilization from Twig Diameter Length Weight Relations

      Ferguson, R. B.; Marsden, M. A. (Society for Range Management, 1977-05-01)
      Overwinter utilization of bitterbrush by big game can be estimated from measurement of the basal diameter and remaining length of a random sample of 100 twigs collected at the end of the browsing season. In this method, regression equations are used to predict unbrowsed twig length or weight. The range manager is thus able to obtain estimates of big game use at less expense, or to survey more area for the same cost than with more time-consuming methods.
    • Fertilization Influences Cattle Diets on Blue Grama Range During Drought

      Allison, C. D.; Pieper, R. D.; Donart, G. B.; Wallace, J. D. (Society for Range Management, 1977-05-01)
      Botanical composition of cattle diets on fertilized and unfertilized blue grama rangeland was evaluated during drought by microhistological examination. Seventy-two percent of all species available were found in the diets. Grass comprised 62% of the yearly diets on the fertilized pasture compared with 73% on the unfertilized pasture. Annual forbs made up 18% of the diets on the fertilized pasture and 8% on the unfertilized pasture. There were no differences in perennial forb composition of the diets among the two pastures. Total grass consumption did not vary among seasons, but composition of individual species did. Blue grama provided the bulk of grass in summer and fall diets with mat muhly furnishing the majority of grass in diets during winter and spring. Perennial forbs were important in winter and spring diets. Annual forbs were major components of diets during summer and fall. Cattle consistently exhibited a greater preference for fertilized blue grama than for unfertilized blue grama. Preference trends for other plants were inconsistent and were influenced mostly by availability.
    • Food Habits of Mule Deer in a Semidesert Grass-Shrub Habitat

      Short, H. L. (Society for Range Management, 1977-05-01)
      Mule deer (Odocoileus hemionus) selectively consumed cactus fruit, browse leaves and fruit, and forbs, when present, on semidesert grass-shrub habitats in southern Arizona. Plant species utilized were generally those that have invaded and proliferated on semidesert grasslands during the twentieth century. The seasonal diet seemed deficient in phosphorus, which may affect deer reproduction and general well being.
    • Multiple Defoliation Effects on Herbage Yield, Vigor, and Total Nonstructural Carbohydrates of Five Range Species

      Buwai, M.; Trlica, M. J. (Society for Range Management, 1977-05-01)
      Western wheatgrass (Agropyron smithii), blue grama (Bouteloua gracilis), and fourwing saltbush (Atriplex canescens) were subjected to multiple defoliations at moderate and heavy intensities during a 2-year period. Most heavy defoliation treatments drastically reduced herbage yield, vigor, and total nonstructural carbohydrates (TNC) of western wheatgrass. Multiple defoliations were detrimental to vigor and herbage yield of blue grama; however, defoliation treatments did not detrimentally affect root TNC levels. All defoliation treatments severely reduced the number of seedstalks, live crown cover, and TNC of fourwing saltbush, but seedstalk length and live crown diameter were less affected by the defoliation treatments. Both fringed sagewort (Artemisia frigida) and antelope bitterbrush (Purshia tridentata) subjected to two moderate defoliations during quiescence and rapid growth (or flowers developing) remained in fair to good vigor at the end of the growing season. However, both species were detrimentally affected if utilized during the later part of the growing season. Defoliation effects were generally more severe when plants were defoliated at a heavy intensity than when defoliated at a moderate intensity during the same phenological stages. Five- and six-pasture rest-rotation grazing systems were proposed to ensure that grazed plants would receive rest following critical late summer foliage utilization.
    • Overwinter Soil Water Recharge and Herbage Production as Influenced by Contour Furrowing on Eastern Montana Rangelands

      Neff, E. L.; Wight, J. R. (Society for Range Management, 1977-05-01)
      On fine-textured range sites in southeastern Montana, contour furrowing increased average overwinter soil water recharge 11 mm on a saline-upland range site and 39 mm on a panspot range site. Increased recharge resulted from decreased late fall and early spring runoff and increased snow accumulation. Overwinter recharge was a function of both antecedent soil water and the amount of water available for recharge. Herbage production was significantly (r = 0.89) related to spring soil water content.
    • Rangeland Production and Annual Rainfall Relations in the Mediterranean Basin and in the African Sahelo Sudanian Zone

      Papanastasis, V. P. (Society for Range Management, 1977-05-01)
      The study of the relationships between annual rainfall and range production in the Mediterranean Basin and the Sahelian Sudanian tropical zones of Africa shows a close correlation between average range production and average rainfall over large geographic areas. For a given amount of rain, net production is higher in the Mediterranean than in the Sahel. The regressions developed show that, on the average, each millimeter of rainfall produces 2 kg/ha of consumable dry matter, or 0.66 Scandinavian Feed Units (FU), in the Mediterranean, whereas in the Sahelian and Sudanian zones these figures drop to 1 kg/ha and 0.40 FU.
    • Responses of Merriam's Turkey to Pinyon-Juniper Control

      Scott, V. E.; Boeker, E. L. (Society for Range Management, 1977-05-01)
      Merriam's turkeys (Meleagris gallapavo merriami) inhabit much of the pinyon-juniper vegetative type in Arizona where ponderosa pines are available for roost sites. A 64% reduction in turkey populations was noted following a pinyon-juniper control program that isolated roost sites 300 m or more from cover. In turkey habitat, cleared areas should not be wider than 90 m to provide good turkey habitat, and strips of cover should be retained as travel lanes to established roost areas.
    • Root Phenology as a Factor of Competition among Grass Seedlings

      Harris, G. A. (Society for Range Management, 1977-05-01)
      Roots of plants express phenology significant to competitive relationships, as do aerial parts. The following developmental stages of root phenology are proposed: (1) germination, (2) initial root growth, (3) rapid extension of root-soil contact, (4) dormancy, and (5) death. Examples of root phenological development in seedlings of three grass species are given to demonstrate effects on competition.
    • Seasonal Variation in Chemical Characteristics of Soil Organic Matter of Grazed and Ungrazed Mixed Prairie and Fescue Grassland

      Dormaar, J. F.; Johnston, A.; Smoliak, S. (Society for Range Management, 1977-05-01)
      At Manyberries and Stavely, Alberta, Mixed prairie and Fescue Grassland ranges were grazed at various intensities for 19 and 22 years, respectively. In 1973, 13 chemical characteristics were determined on the organic matter developed in the soils of the ungrazed and heavy grazed treatments at the two locations. Samples were taken in spring, summer, autumn, and winter. Organic matter characteristics at both locations were closely associated with seasonal fluctuations and grazing-induced pressures; therefore, the time of sampling and the type of management before sampling soils should be defined in range studies. The results further emphasize the fragility of the equilibrium under which the organic matter of the soil of heavily grazed Mixed prairie at Manyberries forms and exists.
    • Soil Properties in Relation to Cryptogamic Groundcover in Canyonlands National Park

      Kleiner, E. F.; Harper, K. T. (Society for Range Management, 1977-05-01)
      A comparative study was made of the soils of a virgin grassland and an adjacent grazed area in Canyonlands National Park. Soils from the virgin site were finer textured than those of the grazed area, and the surface 5 cm contains a significantly lower amount of calcium. In addition, the surface 5 cm of the virgin site contains significantly greater amounts of phosphorus, potassium, and organic matter. Subsurface soils in the two parks are less dissimilar. Cryptogams on the virgin grassland appear to have an important influence on chemical characteristics of the surface 5 cm of soil. The difference in surface soils between the parks may be related to the presence of these species. Data point strongly to light winter grazing as a disturbing influence that has contributed to the differences in the surface soil and in vegetational characteristics between the sites.
    • Toxicity of Extract from Three Larkspur Species (Delphinium barbeyi, Delphinium glaucescens, Delphinium occidentale) Measured by Rat Bioassay

      Olsen, J. D. (Society for Range Management, 1977-05-01)
      Differences in toxicity among species of larkspur have been suspected but until now no standard method of comparison has been made. A rat bioassay has recently been developed and was used to estimate the toxicity of an extract from three larkspur (Delphinium barbeyi, D. glaucescens, and D. occidentale). Delphinium barbeyi was the most toxic and D. occidentale the least, as measured by this bioassay.
    • Yield and Chemical Composition of Coastal Bermudagrass, Rhodesgrass and Volunteer Species Grown on Saline and Nonsaline Soils

      Gonzalez, C. L.; Heilman, M. D. (Society for Range Management, 1977-05-01)
      Yields and chemical composition of coastal Bermudagrass (Cynodon dactylon (L.) Pers.) and Rhodesgrass (Chloris gayana Kunth) grown on saline and nonsaline soils were investigated in the nonirrigated region of the Rio Grande Valley of south Texas. Forage production (3-years average) was 12.9 and 13.8 metric tons per hectare (MT/ha) for coastal Bermudagrass and 16.3 and 13.5 MT/ha for Rhodesgrass in nonsaline and saline soils, respectively, as compared with 7.7 and 7.2 MT/ha for voluntary grasses and forbs. The higher yields of coastal Bermudagrass in saline vs nonsaline soils indicates its greater salt tolerance. Soil salinity did not affect the chemical composition or crude protein content of either grass. Chemical composition of grasses varied yearly, but changes between saline and nonsaline soil treatments followed the same general trend. Growing grasses on saline soils established a mulch on the soil surface and reduced evaporation, but this was not a successful soil reclamation practice, because moisture extraction by roots from saline soil profile caused salt accumulation in the root zone.