• A Comparison of Three Methods for Estimating Forage Disappearance

      Sharrow, S. H.; Motazedian, I. (Society for Range Management, 1983-07-01)
      Three methods of calculating forage disappearance from forage standing crop present on mowed versus protected plots were compared to the actual amount of forage harvested from mowed plots. The method most widely used by range scientists, the difference method, displayed a marked tendency to overestimate forage disappearance during periods of rapid plant growth or when plots were protected for more than 3 weeks. More accurate estimates of forage disappearance were generally obtained using formulae suggested by Linehan et al. (1947) and Bosch (1956) than could be obtained by the difference method.
    • A Mechanical Animal-powered Cow Spacer

      Anderson, D. M.; Mertz, D. I. (Society for Range Management, 1983-07-01)
      The low-cost, practical, easy-to-build, low-maintenance mechanical animal-powered cow spacer described spaces animals that are moving single file through a chute. The spacer unit can be used successfully in conjunction with an automatic electronic weighing/identification system for obtaining accurate daily weight data on individual animals.
    • A Method for Mapping Vegetation Utilizing Multivariate Statistical Techniques

      McLendon, T.; Dahl, D. E. (Society for Range Management, 1983-07-01)
      Principal component analysis and stepwise discriminant analysis were used to map the vegetation of the Pat Welder Ranch on the Texas Coastal Plains into 5 vegetation types based on relative frequency data of the major plant species. These 5 types were shown to be subdivisions of 2 plant communities previously reported for the area by researchers utilizing conventional mapping techniques. In addition to separating the 5 types and classifying the 140 sample points into their respective types, the technique provided a key for field separation of the types based on 3 vegetative variables, and provided indicator species values for rapid field identification of the types. The technique is presented as a means of mapping vegetation with a minimum of human bias, a maximum of repeatability and information content, and maximum applicability.
    • Beef and Forage Production on Contour Furrowed Rangeland Interseeded with Alfalfa

      Kartchner, R. J.; Wight, J. R.; Bishop, J. L.; Bellows, R. A. (Society for Range Management, 1983-07-01)
      Over a 4-year period, average annual herbage production on native range was 603 kg/ha compared to 1,350 kg/ha on contour-furrowed range interseeded with alfalfa. Addition of 112 kg N/ha and 15 kg P/ha on furrowed, interseeded range increased herbage production to 1,658 kg/ha. Forage production on furrowed areas showed more variation in response to precipitation changes than did production on untreated rangeland. Differences in rate of gain by yearling cattle were small in most years, indicating beef production varied largely as a function of stocking rate. Total beef production over a 5-year period was 113 kg/ha on the control, 217 kg/ha on contour-furrowed range with alfalfa interseeded, and 236 kg/ha on furrowed, interseeded range receiving fertilizer. Observations on management of furrowed, interseeded areas were made.
    • Biological Manipulation of Blackbrush by Goat Browsing

      Provenza, F. D.; Bowns, J. E.; Urness, P. J.; Malechek, J. C.; Butcher, J. E. (Society for Range Management, 1983-07-01)
      Domestic goats were used to modify the growth form of blackbrush, a spinescent shrub occurring in nearly monospecific stands on several million hectares of rangeland in the southwestern United States. The objective of this research was to provide data on the responses of blackbrush, goats, and cattle to a biological manipulation program in which winter goat browsing was used to stimulate spring twig production in an attempt to improve fall and winter range for cattle. Goats were stocked at 4 intensities during each winter from 1977 to 1979. Resultant levels of utilization and spring twig production were determined, with increased utilization leading to increased twig production. Browsing improved the nutritional quality of blackbrush by stimulating twig production, and current season's twigs collected during the winter contained more crude protein (6.5 versus 4.6%), phosphorus (0.10 versus 0.08%) and in vitro digestible dry matter (48 versus 38%) than did older twigs. Cattle (heifers) browsed blackbrush pastures during October of 1979. Heifers in pastures unbrowsed by goats consumed primarily older twigs while those in previously browsed pastures consumed primarily current season's twigs. No statistically significant differences in weight response were recorded for heifers using pastures that were, or were not, previously browsed. In previously unbrowsed pastures, however, the average heifer consumed 1.9 times more protein supplement than did her counterpart in previously browsed pastures.
    • Changes in Understory Production Following a Wildlife in Southwestern Ponderosa Pine

      Oswald, B. P.; Covington, W. W. (Society for Range Management, 1983-07-01)
      An area burned by a May, 1972, wildfire and which had been previously sampled in 1972 and 1974 was remeasured in 1980 to determine changes in understory production. The area was stratified into moderately and severely burned areas. By 1974 both herbage and forage production on the moderately burned area were approximately 3 times higher than unburned control sites and did not decline significantly by 1980. While increased herbage production on the severely burned site was similar to that of the moderately burned site in 1974, it declined to only half as much production by 1980. Furthermore, while over 95% of the total herbage production was in forage species for all 3 sampling years on the moderately burned study area, only 30 percent was forage on the severely burned study area by 1980. The decline in total production and shift to non-forage species on the severely burned study area is probably a consequence of heavy grazing which followed the burn.
    • Chlorophyll, Dry Matter, and Photosynthetic Conversion-Efficiency Relationships in Warm-season Grasses

      Bokari, U. G. (Society for Range Management, 1983-07-01)
      This study was conducted to determine the relationship between leaf chlorophyll content, dry matter production, and the photosynthetic conversion efficiency in several warm-season grasses. These included Old World bluestems (Bothriochloa spp.), eastern gamagrass [Tripsacum dactyloides (L)L.], and weeping lovegrass (Eragrostis curvula (Schradd) Nees.). Warm-season grasses usually operate on the C4-photosynthetic pathway and are considered photosynthetically more efficient than the cool-season grasses under high temperature and high light intensity conditions. Samples for chlorophyll analysis and dry matter production were taken from 3 to 5, 0.5 M2 quadrates per pasture at each phenological stage. Photosynthetically active irradiance (400-700 nm) was measured with a quantum sensor. Results indicated close correlation between chlorophyll and dry matter production. Increase in total chlorophyll was associated with increase in dry matter. Chlorophyll a/b ratio remained almost constant throughout the growing season. Solar energy conversion-efficiency ranged from 0.54% to 0.73% for various strains of Old World bluestems, 0.51% for eastern gamagrass and 0.44% for weeping lovegrass. It was demonstrated through this study that warm-season grasses, like many other plants, are not very efficient utilizers of the enormous amounts of incoming solar energy. These grasses maintained high productivity throughout the growing season by maintaining high levels of chlorophyll in the leaves.
    • Comparison of Big Sagebrush Vegetation in Northcentral New Mexico under Moderately Grazed and Grazing Excluded Conditions

      Holechek, J. L.; Stephenson, T. (Society for Range Management, 1983-07-01)
      Vegetation canopy cover on upland and lowland sites inside and outside a 22-year-old exclosure in big sagebrush (Artemisia tridentata tridentata) range was evaluated by sampling for canopy cover. The area outside the exclosure had received moderate use of grazable forage by cattle in the late winter and spring for the past 22 years. The two sites did not show a consistent response to grazing. Big sagebrush canopy cover was higher inside the exclosure on the upland site and higher outside the exclosure on the lowland site. Big sagebrush dominated the canopy cover both inside and outside the exclosure on both sites and relatively little understory was present. Forbs were nearly absent from the area, which is attributed to a past history of heavy sheep grazing. Elimination of grazing had little effect on vegetation composition on both sites studied.
    • Composition and Quality of Mule Deer Diets on Pinyon-Juniper Winter Range, Colorado

      Bartmann, R. M. (Society for Range Management, 1983-07-01)
      Estimates of botanical composition and nutritional quality of mule deer diets on pinyon-juniper winter range in Piceance Basin, Colorado, were based on forage selections of 8 tame animals. Diets contained nearly all browse in early winter, but browse content decreased and forbs increased as winter progressed until April when consumption of new grass growth increased sharply. Dietary crude protein levels were marginally adequate for body maintenance during much of the winter. Levels of dietary in vitro digestible dry matter were inadequate. Browse was considered critical to winter survival of deer in Piceance Basin because it was the most available forage in deep snow. Also, its nutritional value was comparable or better than that of forbs and grasses selected by deer except in April when new plant growth was available. In spite of large variation in diet compositions, deer apparently selected forage mixes to maintain a consistent, although inadequate, diet quality through the critical wintering period.
    • Desert Saltgrass Seed Germination and Seedbed Ecology

      Cluff, G. J.; Evans, R. A.; Young, J. A. (Society for Range Management, 1983-07-01)
      Desert saltgrass [Distichlis spicata var. stricta (Torr.) Beetle] is an important forage species of the saline-alkali basins of the western United States. Revegetation of disturbed sites using saltgrass currently involves the use of rhizomes, but seeding saltgrass with conventional equipment would be much more efficient. The seed and seedbed ecology of desert saltgrass is important to land managers who wish to try new revegetation techniques. The germination of nine collections of saltgrass seed was determined at a wide range of constant and alternating temperatures. The effects of decreasing osmotic potentials on seed germination of one collection was determined using polyethylene glycol and sodium chloride solutions. Seedbed temperatures and moisture potentials were determined during the growing season in two saltgrass stands using thermocouple temperature probes and psychrometers. The temperature regime that produced the highest mean germination (58%) for all nine collections was 10 degrees C for 16 hours alternating with 40 degrees C for 8 hours (10/40 degrees C). Germination response varied significantly (P=0.01) between collections. The best germination was 96% with one collection at the 10/50 degrees C regime, but most collections germinated best with 10/40 degrees C regime. For all collections, at least a 20 degrees C diurnal fluctuation in temperature was needed for germination above 10%. Seeds did not germinate at temperatures as cold as -5 degrees C or as hot as 60 degrees C. Saltgrass germination was enhanced at osmotic potentials of -1 bar, but inhibited by potentials lower than -1 bar. No significant (P=0.01) germination occurred at -15 bars. Field seedbed temperatures reached optimum levels for germination after moisture potentials were below that required for germination. This suggests that saltgrass seed germination is an episodic event in nature, occurring only when moisture events coincide with optimum seedbed temperatures and can leach sufficient salts to raise moisture potentials above -15 bars.
    • Diets of Bison and Cattle on a Seeded Range in Southern Utah

      Van Vuren, D.; Bray, M. P. (Society for Range Management, 1983-07-01)
      Diets of bison (Bison bison) and cattle (Bos taurus) were evaluated on a southern Utah range seeded to crested wheatgrass (Agropyron desertorum) and alfalfa (Medicago sativa). Bison feces comprised 96% grasses and sedges, 4% forbs, and 1% shrubs. Cattle feces comprised 88% grasses and sedges, 4% forbs, and 8% shrubs. Diets were 91% similar, indicating a high potential for competition between bison and cattle.
    • Dog Predation of Domestic Sheep in Ohio

      Blair, B. J.; Townsend, T. W. (Society for Range Management, 1983-07-01)
      Questionnaires were mailed to 300 sheep producers in Ohio during spring 1979, and 218 returns were analyzed. Predation losses from dogs averaged 1.3% of the sampled sheep for a minimum statewide cost of $836,000 in 1978. Physiographic region, month, flock size, and management technique had no significant effect on number or percent killed per flock. Most attacks (P<0.02) occurred at night and morning, and ewes were more vulnerable than lambs or rams (P<0.005).
    • Effect of Cultural Practices on Seeded Plant Communities on Intensively Disturbed Soils

      Doerr, T. B.; Redente, E. F.; Sievers, T. E. (Society for Range Management, 1983-07-01)
      A revegetation technique study was established in a disturbed sagebrush-juniper community in northwestern Colorado in the fall of 1976. The purpose of the study was to identify effective cultural practices for establishing diverse and productive plant communities on disturbed soils. A combination of 4 treatments was applied: (1) altering life form seeding ratios, (2) seeding mixtures, (3) fertilizer, and (4) irrigation. After 4 years there was no significant difference in aboveground biomass production and canopy cover between irrigated and nonirrigated treatments. Fertilization increased production of grasses and shrub growth but depressed forb growth somewhat. The aboveground production of native and introduced mixtures was similar following four growing seasons. In general, introduced grasses out-produced native grasses, introduced forbs produced more than native forbs, and native shrubs out- performed introduced shrubs. Altering ratios among life forms affected shrub biomass more than forb and grass production. The use of different seeding rates indicates that plant community composition will change and may be a function of not only seeding rates but also plant and environmental factors over time and space.
    • Effects of Surface Mining On the Vesper Sparrow in the Northern Great Plains

      Schaid, T. A.; Uresk, D. W.; Tucker, W. L.; Linder, R. L. (Society for Range Management, 1983-07-01)
      A 2-year study was conducted to compare density of vesper sparrow (Pooecetes gramineus) during the breeding season on various aged bentonite clay mine spoils and unmined areas in the Northern Great Plains. The vesper sparrow was one of the most common breeding species with highest densities in grass-sagebrush habitat. Reclaimed and unreclaimed mined spoils had lower sparrow densities which were related to loss of sagebrush habitat. Reserving areas with shrubs between mine spoils, around equipment storage areas, and along haul roads may be necessary during mining and reclamation to attract vesper sparrows in regions where natural regeneration or transplanting of shrubs is difficult.
    • Efficacy of Zinc Phosphide Broadcast Baiting for Controlling Richardson's Ground Squirrels on Rangeland

      Matschke, G. H.; Marsh, M. P.; Otis, D. L. (Society for Range Management, 1983-07-01)
      Zinc phosphide, a potential replacement rodenticide for strychnine or 1080, was field tested on 3 populations of Richardson's ground squirrel. Populations were estimated pretreatment and posttreatment by mark-recapture sampling techniques. We broadcasted a 2% zinc phosphide grain bait at 5.1 kg per swath ha. Swath widths measured 6.1 m, 16.0 m of untreated areas remaining between swaths. Treated populations decreased an average of 85.1 +/- SE 6.4%. Differences in pretreatment and posttreatment population decline between treated and control populations were significant (P = 0.096). No mortality was detected among nontarget animals. The 85.1% efficacy achieved by broadcast baiting exceeded the minimum standard of 70.0% established by the Environmental Protection Agency for the registration of a rodenticide. Registration, however, will require nontarget hazard testing and further efficacy testing in other geographical locations.
    • Estimating Snowberry (Symphoricarpos oreophilus) Utilization by Sheep from Twig Diameter-Weight Relations

      Ruyle, G. B.; Bowns, J. E.; Schlundt, A. F. (Society for Range Management, 1983-07-01)
      Three procedures were used to estimate snowberry biomass browsed at 3 stocking intensities by domestic sheep on mountain range in southwestern Utah. Two regression equations and (percentage of) grazed stems were compared. Each technique gave different estimates of utilization, which were affected by grazing intensity. The two regression equations we developed distinguished between two kinds of sheep browsing, leaf only and entire stem removal. Sheep usually strip only the leaves and rarely is the entire stem removed. The predictive equations accounted for both methods of browsing and related twig diameters to twig leaf weight (R2=.89) and twig plus leaf weight (R2=.90).
    • Fiber Effects on Microhistological Analysis

      Mukhtar, H. K.; Hansen, R. M. (Society for Range Management, 1983-07-01)
      A study was done to illustrate the influence of fiber on the ratio of estimated to actual dry weight fractions of selected species of grasses, forbs, and shrubs in samples analyzed by microhistological analysis. There was no significant relation between the fiber fraction of the plants and the over or under estimations. Forbs were not generally underestimated any more than were grasses or shrubs. The hypothesis is rejected which states that plants with low fiber values are usually underestimated by the microhistological technique.
    • Food Habits of Mountain Goats, Mule Deer, and Cattle on Chopaka Mountain, Washington, 1977-1980

      Campbell, E. G.; Johnson, R. L. (Society for Range Management, 1983-07-01)
      The seasonal food habits of mountain goats, mule deer, and cattle on Chopaka Mountain, Wash., (1977-1980) were determined by fecal analysis. Graminoids represented 84% of the fall diet of cattle, the only period when cattle occurred within the mountain goat range. Mountain goats utilized graminoids (42%) and shrubs (31%) primarily; whereas, mule deer consumed shrubs (45%) and conifers (29%). Dietary overlap was greatest between mt. goats and mule deer (37%) and mt. goats and cattle (32%), and minimal between mule deer and cattle (15%). Considerable intra- and inter-seasonal variation was experienced for all 3 species.
    • Forage Standing Crop and Animal Diets Under Rotational vs. Continuous Grazing

      Sharrow, S. H. (Society for Range Management, 1983-07-01)
      Effects of 5-paddock rotational grazing and continuous grazing were monitored in 1977 and 1978 on an annual grass-subclover (Trifolium subterraneum) pasture. More forage was available to livestock under rotational grazing than under continuous grazing during the midspring through late spring period. However, grazing management had little effect upon forage intake by Romney ewes and their lambs during this period. Live weight gains of ewes and lambs were higher under rotational compared with continuous grazing in the spring, perhaps due to an observed increase in subclover, a highly nutritious feed, in diets of sheep grazing rotationally. In contrast to the spring green-feed period, live weight gains of ewes under rotational grazing were lower than those under continuous grazing during the summer dry-feed period. Poor ewe performance on rotationally grazed pasture during the summer period apparently reflects reduced opportunity for dietary selectivity and, therefore, a lower quality diet compared with that available to ewes on continuously grazed pasture.
    • Gains of Steers and Calves Grazing Crested Wheatgrass

      Hart, R. H.; Balla, E. F.; Waggoner, J. W. (Society for Range Management, 1983-07-01)
      Efficient utilization of pasture requires proper class of livestock, stocking rate, and season of use. Crested wheatgrass was grazed with steers in spring for 3 years at two stocking rates and with calves in fall for 2 years at 2 stocking rates to evaluate alternate uses. Differences in forage production and lengths of grazing season over years produced grazing pressures of 47-79 steer days or 53-73 calf days per metric tonne of forage produced. Steer gains of 0.85-1.20 kg/day were unaffected by grazing pressure, but lighter steers gained faster. Implantation of 36 mg of Ralgro per steer increased daily gains by 13%. Calf gains were 0.15-0.24 kg/day, and decreased with increasing grazing pressure according to the function ADG=0.45-0.0041 (calf days/tonne forage); r2=0.95. Such grazing pressure-gain response functions facilitate comparisons between seasons of use and class of livestock, as well as those between stocking rates, and help range managers make management decisions. Maximum steer gains in spring per hectare and tonne of forage were over 3 and 6 times, respectively, the gains of calves in fall.