• Winter Diets of Mule Deer in Relation to Bitterbrush Abundance

      Burrell, G. C. (Society for Range Management, 1982-07-01)
      During the winters of 1974-1975 and 1975-1976 food habits of the Entiat mule deer (Odocoileus hemionus hemionus) herd were quantified in sites with high, medium and low antelope bitterbrush (Purshia tridentata) abundance. Using a microscopic technique, 27 plant species were identified in fecal samples. Bitterbrush, buckwheat (Eriogonum spp.), arrowleaf balsamroot (Balsamorhiza sagittata) and lupine (Lupinus spp.) combined made up 87%-93% of the diet in the three sites. Bitterbrush use was heavy in sites where it was available; however, as its availability declined, buckwheat replaced it in the herd's diet. In the site with a low bitterbrush abundance lupine also replaced bitterbrush in the herd's diet. Balsamroot use remained relatively constant in all sites during both winters. Changes in bitterbrush abundance significantly affected the diet of the mule deer herd; however, these changes were not thought to adversely affect the winter survival of the deer herd.
    • Weather, Soil and 2,4-D Effects on Tallgrass Prairie in Oklahoma

      Powell, J.; Stritzke, J. F.; Hammond, R. W.; Morrison, R. D. (Society for Range Management, 1982-07-01)
      A study was conducted from 1971 through 1975 in a north central Oklahoma tallgrass prairie to determine effects of (1) different rates of 2,4-D on grass production in fair to good condition areas where forb production was low, (2) repeated applications of 2,4-D on grass and forb production, and (3) species composition and range site growing conditions on grass and forb production responses to 2,4-D application. Five rates 2,4-D (0.00, 0.28, 0.56, 0.84, and 1.68 kg/ha) were applied in 1971 to determine their effects on grass production where forbs had been removed manually prior to spraying. Grass production increases equalled forb production decreases, regardless of whether forbs were reduced by 2,4-D or hand-weeding prior to 2,4-D application. From 1972 through 1975, the same 5 rates of 2,4-D were applied annually on four tallgrass prairie sites differing in range condition, past use, and soil factors. Site and annual growing conditions had more effect on grass production than did 2,4-D applications. There was no evidence of a stimulative growth effect by 2,4-D on grass production. All increases in grass production were accompanied by decreases in forb competition.
    • Water Relations in Soils as Related to Plant Communities in Ruby Valley, Nevada

      Miller, R. F.; Branson, F. A.; McQueen, I. S.; Snyder, C. T. (Society for Range Management, 1982-07-01)
      Distinct patterns of vegetation on ancient lake sediments in Ruby Valley, Nev., define differences in soil-water-plant relations resulting either from differences in depth to ground water or from differences in water-retention capacities of soils deriving water only from precipitation. In order of increasing depth to ground water, dominant plant species are Juncus balticus, Distichlis stricta, Potentilla fruticosa, Elymus cinereus, Sarcobatus vermiculatus, and Chrysothamnus nauseosus. Dominant species on soils in order of increasing water-retention capacity are Artemesia tridentada nova, Chrysothamnus viscidiflorous pumilus, Ceratoides lanata, Artemesia tridentada tridentada, Atriplex nuttallii gardneri, and Atriplex confertifolia. Minimum and maximum levels of soil-water stress measured were systematically related to water-retention capacities of soils. A relationship was defined that permits approximation of amounts of water evapotranspired by different plant communities from percent of area under live plant cover. There are separate relationships, relating plant cover to amounts of plant stress or to amount of water evapotranspired, for habitats that receive water from the water table and those that do not. Levels of osmotic stress encountered in surface soils appear to influence plant-community distribution.
    • Transient Depredation of Early Spring Range; Spotted Cutworms [Amathes c-nigrum (L.)] as a Possible Cause

      Launchbaugh, J. L.; Owensby, C. E. (Society for Range Management, 1982-07-01)
      Destructive feeding by insects delayed early spring development of native shortgrass range nearly 2 months. Although the perennial grasses and most forbs recovered, growth of several plant species was prevented completely for one growing season. Evidence indicated spotted cutworm [Amathes c-nigrum (L.)] larvae may have been responsible.
    • Tiller Defoliation in a Moderate and Heavy Grazing Regime

      Briske, D. D.; Stuth, J. W. (Society for Range Management, 1982-07-01)
      An investigation defining the intensity and frequency of tiller defoliation in brownseed paspalum (Paspalum plicatulum), a native perennial, bunchgrass, was conducted with yearling steers in a moderate and heavy grazing regime. Tillers were marked with alternately colored loops of plastic-coated wire so that an individual tiller could be located on successive sampling dates. Tiller height was reduced 50% within 7 days in the heavy grazing regime. The percentage of leaves defoliated per tiller was 63, 78 and 82 following 4, 7, and 11 days of grazing, respectively. Tillers in the heavy grazing regime were uniformly regrazed at approximately 3 to 4 day intervals. A significant reduction in tiller height did not occur in the moderate grazing regime until after 18 days of grazing and tiller height was reduced only 46% at the end of the 33-day grazing trial. The percentage of leaves defoliated per tiller was 5, 9 and 26 following 11, 21, and 33 days of grazing, respectively. By the end of the moderate grazing trial 82% of the tillers were grazed at least once, 31% at least twice and 10% at least three times. The nonuniform frequency of tiller defoliation and wide range of tiller heights at the end of the moderate grazing trial resulted in an inefficient harvest of available tillers.
    • The Impact of Grazing Systems on the Magnitude and Stability of Ranch Income in the Rolling Plains of Texas

      Whitson, R. E.; Heitschmidt, R. K.; Kothmann, M. M.; Lundgren, G. K. (Society for Range Management, 1982-07-01)
      Results of a 1961-1974 grazing system study on the Texas Experimental Ranch in the Rolling Plains were used to evaluate annual net income stability characteristics for a cow-calf operation. A linear programming risk analysis model was utilized to select optimal combinations of grazing systems which minimized annual negative net income fluctuations. Greatest annual net incomes, expressed in 1979 dollars, were obtained from heavier stocked, continuously grazed systems which received winter feed. For the 1961-1974 period, annual net income stability was not increased by selecting combination of grazing systems. However, when only the last 5 years were included in the analysis, the stability of annual net income was improved by selecting a combination of grazing systems. Supplemental winter feeding did not have a significant effect on annual net incomes. However, under heavier stocking rates the standard deviation of annual net income was approximately doubled when cows did not receive supplemental winter feed. Annual income and income variability was determined to have increased during the last 5 years of the study, relative to the total study period. It is hypothesized that a portion of this increased variability at the heavier rates of stocking is the result of changes in the composition of vegetation. The general increase in variability across all systems indicates that ranch operators may need to consider alternatives for risk management as well as management for profits.
    • Sweetvetch Seed Germination

      Redente, E. F. (Society for Range Management, 1982-07-01)
      Sweetvetch (Hedysarum boreale Nutt. var. boreale) is a potentially important revegetation species for drastically disturbed lands and range improvements in western North America. The germination of sweetvetch was studied under various temperature, light, and moisture conditions. It was found that sweetvetch can germinate under a wide range of temperature and light conditions following physical scarification of the seed coat. Under constant temperatures optimum germination occurred at 15 degrees C and 20 degrees C, while under alternating temperature optimum germination occurred at 15-25 degrees C and 20-15 degrees C (for 8 hours and 16 hours, respectively, in each case). Dark treatments resulted in greater germination than light treatments. When temperature and light conditions were held constant and moisture conditions varied, the germination of sweetvetch declined rapidly at osmotic potentials below -7.5 bars.
    • Suppression of Knapweed Invasion by Crested Wheatgrass in the Dry Interior of British Columbia

      Berube, D. E.; Myers, J. H. (Society for Range Management, 1982-07-01)
      We resampled an experimental plot established 11 years previously in the dry interior of British Columbia to test the ability of crested wheatgrass and Russian wild rye to suppress the invasion of diffuse knapweed. Knapweed density was high in non-seeded plots, moderate in Russian wild rye plots, and very low in crested wheatgrass plots. Watering experiments indicated that lack of soil moisture resulted in high seedling mortality and prevented knapweed invasion into crested wheatgrass plots. Diffuse knapweed reinvaded a similar experimental area in a higher rainfall region of B.C., which shows that the same cultural practices will have different effects on knapweed suppression under different climatic regimes.
    • Sheep as a biological control agent for tansy ragwort

      Sharrow, S. H.; Mosher, W. D. (Society for Range Management, 1982-07-01)
      Tansy ragwort (Senecio jacobaea) is a biennial weed commonly found on forest and pasture lands in the maritime regions of the Pacific Northwest. Pyrrolizidine alkaloids in tansy ragwort, when consumed by most types of livestock, produce progressive and irreversible liver damage. Sheep, however, appear immune to these alkaloids. To evaluate the possibility of using sheep to suppress tansy ragwort in cattle pastures, 100 plants were marked and their status followed during 1977 and 1978 in pastures grazed by cattle alone and in pastures grazed by both cattle and sheep. Total tansy ragwort mortality did not differ between pastures. However, the cause of mortality did differ. Mortality on the cattle-grazed pasture was predominately due to completion of the plant's biennial life cycle (blooming and seed set), while most plant mortality on the sheep plus cattle pasture appeared to be the result of grazing. The data suggest that sheep may be used as a biological control agent to suppress tansy ragwort populations by reducing their ability to produce seed.
    • Meadow Forage Production as Influenced by Fertilization in a Dry Year

      Gomm, F. B. (Society for Range Management, 1982-07-01)
      During drought years, stream flow is often insufficient to irrigate normally flooded native meadows. Herbage production of the meadow is reduced, haying operations are suspended, and the available forage is grazed by cattle. Fertilization of meadows in eastern Oregon is done in the late fall or early spring before the availability of irrigation water for the following growing season is known. This study was initiated in 1977, following a severe winter drought, to determine the effect of fertilizing meadows in a dry year. Urea fertilizer was applied at 13 rates (0 to 745 kg N/ha). Maximum forage production of 1,000 kg/ha occurred about mid-July for the check treatment. Production was not increased at fertilizer rates of 0 to 50 kg N/ha, but were increased up to 1,600 kg at fertilizer rates of 95 to 745 kg N/ha. Crude protein concentrations in the forage were similar to those measured in years of normal rainfall. Herbage NO3- N levels were considered nontoxic at fertilizer rates less than 540 kg N/ha. It appears that during years of low precipitation, with customary rates of fertilization (90-110 kg N/ha), forage production will be increased slightly, forage quality will be about normal, and the danger of nitrate poisoning will be nil.
    • Long-Term Plant Establishment on Mined Lands in Southeastern Montana

      Holechek, J. L.; DePuit, E. J.; Coenenberg, J.; Valdez, R. (Society for Range Management, 1982-07-01)
      Research was conducted on strip mined lands at Colstrip, Mon., over a 6-year period to evaluate germination, survival and cover characteristics of fairway crested wheatgrass (Agropyron cristatum), critana thickspike wheatgrass (Agropgron dasystachyum), ranger alfalfa (Medicago sativa), and fourwing saltbush (Atriplex canescens). All 4 species showed good initial establishment and long-term survival/growth even though subjected to 2 consecutive years of drought when growing season precipitation was less than 50% of the mean. Nitrogen and phosphorus fertilizer application after emergence had no effect on initial or long-term survival of any species. However plant canopy and litter cover were increased for all species except fourwing saltbush by fertilizer application. There was little invasion of native species into the study area. Critana thickspike wheatgrass is a native species that appears well suited for seeding mixtures on mined lands in the study area. However, because of aggressiveness, the use of fairway crested wheatgrass is not recommended in mixtures from which a diversity of native species is the vegetation goal.
    • Integration of Burning and Picloram Pellets for Macartney Rose Control

      Gordon, R. A.; Scifres, C. J.; Mutz, J. L. (Society for Range Management, 1982-07-01)
      Picloram pellets (5% active ingredient [a.i.]) applied at 1.1 kg/ha (a.i.) in June or September after burning Coastal Prairie in February resulted in excellent control of Macartney rose regrowth for at least two growing seasons. Picloram pellets (5% or 10% a.i.) at 1 kg/ha (a.i.) also effectively controlled Macartney rose when applied directly into the ash immediately after burning in the winter or early spring. Generally, there was no difference between the 5 and 10% formulations of picloram pellets applied at the same rate of active ingredient relative to Macartney rose control. Higher application rates (1.7 or 2 kg/ha [a.i.]) tended to improve Macartney rose regrowth control on burned areas only slightly compared to that from 1 kg/ha (a.i.) of the picloram pellets, regardless of formulation. Picloram pellet application extends the beneficial effects of prescribed burning on Macartney rose-infested rangeland. Prescribed burning eliminates the debris which prevents uniform grazing distribution and poses livestock handling problems following herbicide applications.
    • Individual Plant Treatments for Controlling Redberry Juniper Seedlings

      Ueckert, D. N.; Whisenant, S. G. (Society for Range Management, 1982-07-01)
      Cutting at the soil surface or hand grubbing to a depth of 5 to 15 cm completely controlled redberry juniper seedlings that averaged 34 cm in height in the southwestern Edwards Plateau of Texas. Foliar sprays (0.5% a.i.) of bromacil, hexazinone, 2,4,5T + picloram (1:1), and picloram in water carriers as well as picloram in a 2:98 (v:v) diesel fuel/water emulsion applied in fall or spring also completely controlled juniper seedlings. Foliar sprays of dicamba (0.5% a.i.) completely controlled redberry juniper seedlings in a wet spring and 76% of the seedlings in a dry fall. Pelleted or granular formulations of dicamba, tebuthiuron, and picloram at 2.2 to 4.5 kg (a.i.)/ha as individual-plant treatments did not satisfactorily control juniper seedlings in a dry fall or a wet spring. Cutting or hand grubbing were the least cost alternatives ($23.14/ha), based on 1979 prices for controlling stands averaging over 2,000/ha. Dicamba as a 0.5% foliar spray was the least cost herbicide spray evaluated ($28.24/ha), followed closely by bromacil ($29.28/ha), hexazinone ($32.10/ha), and 2,4,5-T + picloram ($32.44/ha).
    • Honey Mesquite Control and Forage Response in Crane County, Texas

      Jacoby, P. W.; Meadors, C. H.; Foster, M. A.; Hartmann, F. S. (Society for Range Management, 1982-07-01)
      Replicated field plots of honey mesquite (Prosopis glandulosa var. glandulosa) were aerially treated with herbicides in 1977 near Crane, Texas. Plots were evaluated for 3 years to determine efficacy of nine herbicide formulations. Of the herbicides studied 3,6-dichloropicolinic acid was the most effective. Sprayed plots produced twice as much forage as unsprayed areas with several species of grass showing significant increases in production. Forb response was not significantly different between treated and untreated plots. Most of the forage response occurred 1 m from the tree base rather than at 3 and 5 m from the tree.
    • Herbage Yield of Fertilized Cool-Season Grass-Legume Mixtures in Western Nebraska

      Schultz, R. D.; Stubbendieck, J. (Society for Range Management, 1982-07-01)
      Herbage yield from five cool-season grasses (meadow bromegrass [Bromus biebersteinii Toem and Schult.], smooth bromegrass [Bromus inermis Leyss.], intermediate wheatgrass [Agropyron intermedium (Host) Beauv.], Russian wildrye (Elymus junceus Fisch.], crested wheatgrass [Agropyron cristatum (L.) Gaertn.]) in mixtures with alfalfa [Medicago sativa L.] or cicer milkvetch [Astragalus cicer L.] and with the two legumes in pure stands at two dates of harvest (June 5, June 26) and with four rates of fertilizer (0 kg N/ha-0 kg P/ha, 0 kg/ha-22 kg P/ha, 45 kg N/ha-22 P/ha) was studied in western Nebraska in 1977 and 1978. Higher precipitation and more complete stand establishment during the second year caused dry matter production to be higher in 1978 than 1977. Herbage yields were greater for the alfalfa-grass mixtures than the cicer milkvetch-grass mixtures. Dry matter yields were greater for the June 26 harvest than the June 5 harvest during both years which was attributed to the extra 3 weeks for growth to occur. Plots fertilized with 45 kg N/ha-22 kg P/ha and 45 kg N/ha-0 kg P/ha produced more herbage than plots receiving the other treatments during both years. The highest yields were recorded for the intermediate wheatgrass- and crested wheatgrass-legume mixtures and the lowest yields for the Russian wildrye-legume mixtures during the 2 years of this study.
    • Frequency Sampling for Microscopic Analysis of Botanical Compositions

      Johnson, M. K. (Society for Range Management, 1982-07-01)
      There is confusion in the literature as to the underlying basis for quantifying botanical mixtures microhistologically. The relationship between particle density and frequency of occurrence is useful for estimating numbers of individuals contained in a large number of sampling units. Applied studies do not adequately report the mathematical rationale behind estimation procedures. This paper explains why certain sampling and quantification procedures are useful when applied to microscope analysis of herbivore diet samples.
    • Forage Response to Overstory Reduction on Loblolly-Shortleaf Pine-Hardwood Forest Range

      Wolters, G. L.; Martin, A.; Pearson, H. A. (Society for Range Management, 1982-07-01)
      Herbage and browse production after selectively cutting uneven-aged stands of loblolly-shortleaf pine to various densities were generally related to residual pine basal area and site quality. Exceptions were at least partially the result of shrub and hardwood crown cover development on the triennially burned range. Uniolas were the principal forage species under stands having high residual pine basal area, bluestems were the major forage component on clearings. Browse made up about one-fourth of the forage under stands having high residual pine basal area but represented considerably lower proportions on clearings.
    • Flushing Ewes on Chemically Cured Hill Pastures

      Tart, D. L.; Sharrow, S. H. (Society for Range Management, 1982-07-01)
      A study was conducted to evaluate the use of chemically cured pasture as a flushing feed for ewes in western Oregon. In 1976 paraquat (0.28 kg/ha) was used to chemically cure hill pasture forage when perennial ryegrass (Lolium perenne L.) and tall fescue (Festuca arundinacea Schreb.) were in early anthesis. Crossbred ewes grazed the pastures from 17 days after the start of mating. Forage available during the breeding season had a higher protein content (P<.50) on paraquat-treated than on untreated pasture. Paraquat treatment had no effect, however on forage dry matter digestibility (P<.05). Chemical curing greatly reduced herbage yield, probably due to increased shattering and decomposition losses. Summer rainfall may have intensified the latter problem. Using chemically cured forage as flushing feed did not improve ewe live weight gains or lambing performance over untreated forage. Therefore, flushing ewes on chemically cured pasture appears to have little potential in areas, such as western Oregon, where summer rainfall is likely to occur.
    • Factors Affecting Budbreak in Honey Mesquite in West Texas

      Goen, J. P.; Dahl, B. E. (Society for Range Management, 1982-07-01)
      Budbreak in honey mesquite in west Texas rarely occurs prior to the last spring frost. We monitored many trees from 1970 to 1980 attempting to better correlate mesquite mortality from herbicides to growth stage. In doing so, we found clues to the probable conditions triggering budbreak. Budbreak was closely correlated to daily minimum winter temperatures but totally unrelated to winter maximum, mean, or soil temperatures. Our data showed that the higher the number of consecutive days with minimums below -1°C during January 15 to February 14, the earlier spring budbreak would occur. Once chilling requirements were met, date of budburst then became a function of relatively warmer daily minimum temperatures from February 15 to March 15. Being able to predict budbreak (from equations developed herein) as early as February 15 and/or March 15 should give ranchers and herbicide applicators 4 to 6 weeks lead time in planning mesquite control programs.