• Basal-Area Growth and Reproductive Responses of Thurber Needlegrass and Squirreltail to Weed Control and Nitrogen Fertilization

      Eckert, Richard; Spencer, John S. (Society for Range Management, 1982-09-01)
      Effects of weed control and added nitrogen were evaluated in terms of basal area growth, number of reproductive culms, seed yields, and test weight and germination of seed from individual plants of squirreltail (Sitanion hystrix) and Thurber needlegrass (Stipa thurberiana) from 1974 to 1979. Basal-area growth of Thurber needlegrass plants continued during the study period but at a reduced rate during dry years. Parts of squirreltail crowns died during dry periods. A reduction in competition by weed control and added nitrogen stimulated basal area growth of Thurber needlegrass, enhanced germination of squirreltail seed, and increased the number of reproductive culms and seed yield of both species, particularly in years of high precipitation. Germination of squirreltail was much greater than that of Thurber needlegrass. Results are discussed in relation to community ecology, range improvement practices, and seed production for commerce.
    • Buried, Viable Seeds and Their Relation to Revegetation after Surface Mining

      Iverson, Louis R.; Wali, Mohan K. (Society for Range Management, 1982-09-01)
      The quantity and quality of seeds present in prairie soils prior to surface mining were determined in this study. Samples were collected near Beulah in western North Dakota from 4 sites (1 each from grazed and ungrazed areas, 1-year old stockpiled topsoil, and a fresh stockpile). Samples were taken from 3 depths and allowed to germinate in a growth chamber for 16 months. The grazed site had a seed density of over 7,700 seeds m2 (43% were from weed species), and the ungrazed site had 3,900 seeds m-2 (7% were weeds); the stockpiled topsoils had very low seed densities. Seed density and diversity decreased with depth on both the grazed and ungrazed sites; this was especially true for the grazed site where 94% of the seeds were found in the top 7.5 cm. Comparisons were made between the seed banks and the aboveground vegetation of the unmined site and 4 mined sites (ages 1-4 years after reclamation). Analysis indicated that seeds of the most prevalent colonizers after reclamation [e.g. summer cypress (Kochia scoparia), green pigeongrass (Setaria viridis), and Russian thistle (Salsola collina)] were not present in the topsoil; rather, they immigrated from the surrounding areas. Several species which were present in the seed bank [e.g. rough penny royal (Hedeoma hispida), buck-horn (Plantago patagonica), white sage (Artemisia ludoviciana), fringed sage (A. frigida), and wormwood (A. absinthium)] were found in the aboveground vegetation of 3- and 4-year-old mined sites, and at the unmined site. Evidence from seed banks and extant aboveground vegetation suggests that both seed dispersal in time (dormancy) and dispersal in space (immigration) are important in determining the type of vegetation on mined areas after topsoil has been replaced.
    • Changes in Vegetation and Grazing Capacity Following Honey Mesquite Control

      McDaniel, Kirk C.; Brock, John H.; Haas, Robert H. (Society for Range Management, 1982-09-01)
      Honey mesquite kill and suppression, vegetation response, and changes in grazing use and capacity were evaluated following brush control in north-central Texas. Tree grubbing was most effective for eliminating honey mesquite, but because of soil and plant damage the treatment did not increase grazing capacity or improve range condition compared to nontreated rangeland. Aerial application of 2,4,5-T + picloram was more effective in killing and defoliating honey mesquite than 2,4,5-T alone, but both treatments significantly increased forage production. The 2,4,5-T + picloram and 2,4,5-T sprays provided a 7 to 16% increase in grazing capacity over a 4-year period on light and heavy honey mesquite infested pastures, respectively.
    • Crested Wheatgrass Vigor as Affected by Black Grass Bug and Cattle Grazing

      Ansley, R. James; McKell, C. M. (Society for Range Management, 1982-09-01)
      Light to moderate populations (50-200 per m2) of black grass bugs in a seeded monoculture of crested wheatgrass appeared to reduce plant vigor. Vigor of ungrazed plants was compared to plants grazed only by black grass bugs and plants grazed by black grass bugs and cattle. Generally, vigor decreased as levels of grazing increased. Leaf length, seedhead height, root crown nonstructural carbohydrates, and plant color correlated positively with vigor while functions of axillary tillering such as basal area and seedhead density correlated negatively with vigor. Cattle grazing was not in excess of intensities recognized as proper for the area.
    • Describing the Grass Inflorescence

      Allred, Kelly Wayne (Society for Range Management, 1982-09-01)
    • Early Secondary Succession Following Restoration and Reseeding Treatments in Northern Arizona

      Hessing, M. B.; Johnson, C. D. (Society for Range Management, 1982-09-01)
      Reseeding, with and without disc harrowing, building of water bars, and piling of slash on utility corridors (restoration), was studied on access roads and pylon sites following construction of the 500 kV Navajo Project Southern Transmission Line in 1973. Reseeding was not successful. Restoration either had no significant positive effect on revegetation or slowed plant succession in the following 4-year period, or had a deleterious effect on amount and quality of revegetation due to the destruction of climax vegetation which survived powerline construction.
    • Effect of Grazing Horses Managed as Manipulatros of Big Game Winter Range

      Reiner, Richard J.; Urness, Philip J. (Society for Range Management, 1982-09-01)
      A sagebrush-grass range in northern Utah, a critical winter area for deer and elk, was grazed by domestic horses in order to evaluate their potential to reduce selectively herbaceous vegetation which competes with bitterbrush (Purshia tridentata), an important big game winter forage. The diets of horses were recorded during spring and summer grazing under two stocking levels on small pastures. Horses consumed largely grass species throughout the study period in this high seral community. Forbs were important forage only under heavy stocking. No use of bitterbrush was recorded. Rate of forage disappearance, expressed on a per-animal-weight basis, was found to be lower on heavily stocked pastures. All pastures grazed by horses responded with increased seasonal twig production of bitterbrush over the non-grazed state. Seasonal twig production was greatest in response to heavy stocking during early July.
    • Effect of Range Condition on Density and Biomass of nematodes in a Mixed Prairie Ecosystem

      Smolik, J. D.; Lewis, J. K. (Society for Range Management, 1982-09-01)
      Nematode density and biomass were determined by taxa from exclosures in excellent or fair range condition in western South Dakota. Density of plant feeding nematodes in both treatments varied from 2 to 6 million/m2 to a depth of 60 cm. Biomass of plant feeders was greater in the excellent condition range due principally to high numbers of dagger nematodes (primarily Xiphinema americanum). The main contributors to biomass estimates in fair range condition were Tylenchida, principally stunt and spiral nematodes. Biomass of predaceous forms was similar to that of plant feeders. Microbial feeders, although numerous, constituted a relatively small proportion of biomass in both treatments. Approximately 70% of nematodes in all trophic levels occurred above 20-cm sampling depth in both range conditions. Stunt nematodes were nearly limited to the upper 10 cm of soil, with spiral nematodes predominating with increasing depth, particularly in fair condition range. Results indicate that nematode constitute a major portion of the faunistic biomass in a mixed prairie ecosystem.
    • Effects of Burning on the Algal Communities of a High Desert Soil near Wallsburg, Utah

      Johansen, Jeffrey R.; Javakul, Adehara; Rushforth, Samuel R. (Society for Range Management, 1982-09-01)
      A recently burned area near Wallsburg, Wasatch County, Utah, was sampled to determine if differences existed between the soil algal flora of a burned area and that of an adjacent ecologically similar unburned area. Soil samples were cultured and analyzed to determine presence and relative frequency of living algae. The frequency of visible algal patches present after eight days of culturing was much higher in the unburned soil samples than in the burned samples. Percent relative frequencies and absolute densities of diatoms were also determined. Diatom floras of the two areas were very similar. However, the absolute densities of diatoms were significantly greater in the unburned samples. The major effect of the burn was to decrease algal biomass, although the flora remained remarkably similar.
    • Effects of Controlled SO2 Exposure on Net Primary Production and Plant Biomass Dynamics

      Dodd, J. L.; Lauenroth, W. K.; Heitschmidt, R. K. (Society for Range Management, 1982-09-01)
      Objectives of this study were to determine effects of low level SO2 fumigation on above- and belowground plant biomass dynamics and aboveground net primary production. With two exceptions we were unable to measure significant effects on these parameters. Rates of increase in rhizome biomass over the 4-year period of the study were reduced by SO2 and indicate that longterm exposure of this grassland to low level SO2 may ultimately reduce the vigor of the perennating organs to a point where above- and belowground biomass dynamics will be altered, net primary production will be reduced, and species composition will be modified. In addition, production of Bromus japonicus, a cool-season annual grass, was reduced by SO2 fumigation.
    • Energy Analysis of Oklahoma Rangelands and Improved Pastures

      Klopatek, J. M.; Risser, P. G. (Society for Range Management, 1982-09-01)
      The energy costs of beef production were examined for native rangelands and improved pastures grazing systems in the State of Oklahoma. Energy analysis models were constructed to examine the necessary energy inputs and outputs of the grazing systems. Energy requirements to maintain improved pasture systems ranged from 10 to 100 times that to maintain native rangeland. Comparing only fossil-fuel expenditures showed that rangelands are two to three times more efficient producers of beef than the improved pastures, although their beef production is considerably lower per hectare. Regression analysis indicates that the maximum possible efficiency of beef production from fossil-fuel subsidies in Oklahoma is approximately 14.8%.
    • Establishing Circular Plot Boundaries with a Wedge Prism and an Adjustable Target Pole

      White, Elton W.; Lewis, Clifford E. (Society for Range Management, 1982-09-01)
      A target pole used with a wedge prism to establish a one-size circular plot has been modified so that one target pole and prism can be used to establish the perimeter of circular plots of different sizes by a simple adjustment.
    • Establishment of Honey Mesquite and Huisache on a Native Pasture

      Meyer, R. E.; Bovey, R. W. (Society for Range Management, 1982-09-01)
      Scarified honey mesquite [Prosopis juliflora (Swartz) DC. var. glandulosa (Torr.) Cockerell] and huisache [Acacia farnesiana (L.) Willd.] seeds were broadcast on a native pasture to study their ability to establish plants under several mechanical and chemical treatments. Plots were subjected to mowing, disking, or herbicide treatments. After 5 years, no more than 1 and 2% of the original honey mesquite and huisache seeds ultimately produced established plants. However, no treatment entirely prevented the establishment of either species. During the 3- to 5-year period following seeding, honey mesquite plant numbers increased with close mowing (3 to 5 cm high) and high mowing (25 to 30 cm high) without fertilization. Huisache plant numbers increased most prominently on the untreated plots, on plots mowed close and high but without fertilizer, and on plots sprayed with a 1.1 kg/ha of 2,4-D [(2,4-dichlorophenoxy)acetic acid] the year of seeding. Overall, the most effective treatment for controlling both species was 1.1 kg/ha of picloram (4-amino-3,5,6-trichloropicolinic acid) applied during the fall following seeding in the spring. Neither the treatments nor the brush cover affected herbaceous vegetative cover or estimated herbage yield during the 3- to 5-year period following seeding.
    • Estimating Browse Production by Deerbrush [Ceanothus integerrimus]

      Bartolome, James W.; Kosco, Barbara H. (Society for Range Management, 1982-09-01)
      This architectural model is designed to significantly refine browse weight estimates for deerbrush (Ceanothus integerrimus). Basal diameter of branches arising from the primary stem (2nd order stems) predicted leaf and branch weights with r2 = 0.97 using an allometric transformation in linear regression. Estimates based on secondary stem basal diameter rather than terminal shoots may be useful in a large number of similar shrub species.
    • Forage Yield and Quality in a Great Basin Shrub, Grass, and Legume Pasture Experiment

      Rumbaugh, M. D.; Johnson, D. A.; Van Epps, G. A. (Society for Range Management, 1982-09-01)
      A study was conducted in central Utah to determine the forage and protein yield relationships among the components of grass-shrub-legume plantings in a semiarid rangeland pasture. Forage and protein yields of crested wheatgrass (Agropyron cristatum) and total herbage increased when fourwing saltbush shrubs (Atriplex canescens) or legumes (Astragalus cicer, A. falcatus, or Medicago sativa) were grown in association. The shrub and legume species directly contributed to the increase in these yields and to more rapid regrowth of crested wheatgrass.
    • Habitat Relationships of Basin Wildrye in the High Mountain Valleys of Central Utah

      Walker, G. R.; Brotherson, J. D. (Society for Range Management, 1982-09-01)
      Habitat relationships between stands of basin wildrye (Elymus cinereus) and adjacent sagebrush-grass steppe were studied in the Strawberry Valley of central Utah. Fifteen sites of basin wildrye and 15 adjacent sites of sagebrush-grass steppe were selected and sampled for various biotic and abiotic environmental variables. Stands of basin wildrye were dominated by this grass (90% composition). The adjacent sagebrush-grass steppe exhibited more diversity of species and life forms. Basin wildrye and badger diggings were correlated 95% of the time. Potassium concentrations (P<.05) and soil depth (P<.01) were significantly greater in the basin wildrye sites. Secondary successional patterns were observed on disturbed sites.
    • In Vitro Digestibility of South Texas Range Plants Using Inoculum from Four Ruminant Species

      Blankenship, Lytle H.; Varner, Larry W.; Lynch, Gregory W. (Society for Range Management, 1982-09-01)
      Differences in the in vitro digestible dry matter (DDM) of 26 native forage species in south Texas were determined using rumen inoculum from white-tailed deer, sheep, goat, and steer. The mean DDM of all forages was significantly different for each animal species (P<.05). Deer was the most efficient overall digestor of forbs, shrubs, and prickly pear. Of the grasses sampled, the goat was the most efficient digestor with the steer second. In overall efficiency of digestion of all forages tested, the deer was highest with 52.5%, goat with 49.2%, sheep with 47.5%, and steer with 46.6%. These data indicate that caution should be exercised when using inoculum from one ruminant species to estimate DDM for another species. Certain plant species were determined to meet the TDN requirements for maintenance levels of the four ruminants.
    • Interrelationships of Huisache Canopy Cover with Range Forage on the Costal Prairie

      Scifres, C. J.; Mutz, J. L.; Whitson, R. E.; Drawe, D. L. (Society for Range Management, 1982-09-01)
      Grass production was monitored based on seasonal harvests under various canopy covers of huisache on a Coastal Prairie blackland range site during 1978 and 1979. Grass production (Y) was not decreased in 1978, compared to that on essentially brush-free areas, until huisache canopy cover (X) exceeded 30% based on the relationship, the average of Y = 2,346 + 20X - $0.62X^2. Texas wintergrass standing crop apparently increased as huisache canopy cover increased to 25%, and its growth during winter partly compensated for standing crop losses of warm season species during the winter. In 1979, the contribution of the cool-season species was masked by greater production of warm-season species. Consequently, grass production decreased with increasing huisache canopy cover according to the relationship, the average of Y = 4,047 - 14.9X - $0.29X^2. Based on the functional relationship the average of Y = a – b1X-b2X^2, coefficients of determinations (r2) ranged from 0.50 to 0.96 when estimates of annual production of grasses or production for the growing season only were regressed against huisache canopy cover.
    • Partial Defoliation Stimulates Growth of Arizona Cottontop

      Cable, Dwight R. (Society for Range Management, 1982-09-01)
      Responses of Arizona cottontop to partial defoliation were determined by removal of the terminal growing point in the latter half of July of basal culms that were in various stages of development at the time. If soil moisture was available cottontop responded well to grazing throughout its growing season. Removal of the growing point stimulated axillary shoot growth regardless of the stage of development.