• Biomass Estimation for Four Common Grass Species in Northern Arizona Ponderosa Pine

      Andariese, S. W.; Covington, W. W. (Society for Range Management, 1986-09-01)
      Vegetation allometric relations were examined for 4 important grass species in southwestern ponderosa pine (Pinus ponderosa). Logarithmic regressions were developed relating aboveground biomass to basal area, height, and number of seedheads, as well as 3 factors: overstory type (pole, yellow pine), burning treatment (unburned, prescribed burn 2-, 5-, and 7-yr previously), and site (3 locations). Basal area was defined as longest basal diameter multiplied by the widest perpendicular diameter. Of the metric variables, basal area proved to be the best predictor of biomass. Height and number of seedheads did little to increase R2 values. Burning treatment was a significant factor for Sitanion longefolium and Muhlenbergia montana. Overstory type significantly affected Poa fenderiana and Festuca arizonica equations. Site effects were important for all but Sitanion longefolium. When biomass regressions are used for species such as these, sampling efficiency can be improved by including factors such as overstory type, burning history, and locale. Final regression equations relating biomass of each species to basal area and significant factors were significant at p<0.05 and had adjusted R2 values ranging from 0.81 to 0.87. A validation test using 20% of the data not used in developing the regressions indicated that these equations are adequate predictors. When used with double sampling, weight prediction based on basal area indices should provide a more objectively measured predictor than percent cover.
    • Botanical Composition and Nutritional Quality of Alpaca Diets in Two Andean Rangeland Communities

      Reiner, R. J.; Bryant, F. C. (Society for Range Management, 1986-09-01)
      Our objectives were to measure alpaca (Lama pacos) diet quality and botanical composition seasonally on 2 high elevation range-sites (bofedal and Altiplano) in the Andes Mountains of Peru. The bofedal site was a perennially green sedge and forb community located at 5,000 m elevation. The Altiplano site, located at 3,190 m, was predominately bunchgrass. We collected diets from free-ranging, esophageally fistulated alpacas at each site. Alpaca diets at both sites were highest in grasses during the wet and early dry season. As the dry season progressed, bofedal alpaca diets were comprised largely of sedges and reeds (78%) while Altiplano diets remained predominantly grasses (68%). Forb consumption varied annually between 8 and 29% of the diet on both sites. Crude protein (CP) in bofedal diets (12.3%) averaged higher than on the Altiplano (10.2%). Values were lowest during August (6.1%) on the Altiplano and in July (8.0%) on the bofedal. In vitro organic matter digestibility (IVOMD) of alpaca diets on the bofedal (63%) was similar to the Altiplano site (64%) when averaged for all seasons. IVOMD was lowest during August (49%) at the Altiplano site and in October (50%) on the bofedal. Low dietary CP and IVOMD during the late dry season (Aug.-Oct.) denote this period as nutritionally critical for both sites.
    • Cultural Practices for Establishing Fourwing Saltbush within Perennial Grass Stands

      Petersen, J. L.; Ueckert, D. N.; Potter, R. L. (Society for Range Management, 1986-09-01)
      Establishment of fourwing saltbush [Atriplex canescens (Pursh) Nutt.] on rangelands in western Texas could improve forage production and quality. Three experiments were conducted to evaluate establishment and growth of fourwing saltbush in grass stands as affected by width of tilled seedbed, fertilization, and competition from various grasses. Four-month-old seedlings were transplanted on 1.8-m centers and seeds were planted in 10-cm-wide, ripped areas and in 46- or 91-cm-wide, tilled strips within a dense stand of sideoats grama [Bouteloua curtipendula (Michx.) Torr.]. Transplanted seedlings were fertilized with nitrogen (N) (50 kg/ha), phosphorus (P) (50 kg/ha), or N+P (50+50 kg/ha). Survival and size of transplanted seedlings were significantly (P is less than or equal to 0.01) greater after 17 months in tilled than in ripped strips. Standing crops of competing vegetation were about 50% greater in ripped than in tilled areas. Fertilizer did not affect survival of fourwing saltbush seedlings or standing crops of competing vegetation. However, P increased (P is less than or equal to 0.05) mean canopy height and diameter of 17-month-old fourwing saltbush seedlings 50 and 67%, respectively, compared to those of plants receiving no fertilizer or N. Very few seedlings established following direct seeding. Survival and growth of transplanted fourwing saltbush seedlings were significantly (P≤0.05) greater in competition-free plots than in interspaces between rows of various species or short-, mid-, and tall grasses, and survival decreased as height of grasses increased.
    • Diet Quality of Steers Grazing Three Range Sites in South Florida

      Long, K. R.; Kalmbacher, R. S.; Martin, F. G. (Society for Range Management, 1986-09-01)
      Crude protein and in vitro organic matter digestibility (IVOMD) were studied in diets of 4 or 5 esophageally fistulated steers grazing pine-palmetto (PP), fresh-water marsh (FM), or transition (T) sites. Crude protein in summer diets on FM (10.6%) was higher (P>0.05) than that on PP (7.3%) and T (7.3%). There were no differences among sites for diet crude protein content (7.1%) during winter. There were no differences (P>0.05) in diet IVOMD among 3 range sites in summer (46.8%) or winter (33.7%). Data suggest that diets selected on PP and T sites could meet protein requirements for dry cows in summer but not winter. Diets from the FM site could meet protein needs of lactating cows in summer, but in winter crude protein would be deficient for dry cows because of senescence of the major grass, Panicum hemitomon. Energy from the 3 sites in summer would be marginal for maintenance of dry cows, but in winter none of the sites would be adequate without energy supplementation.
    • Effect of Various Grazing Systems on Type and Density of Cattle Trails

      Walker, J. W.; Heitschmidt, R. K. (Society for Range Management, 1986-09-01)
      Number and kinds of cattle trails may have a dramatic impact on relative amount of bare soil and subsequently on amount and rate of soil erosion. The objective of this study was to quantify the effect of a cell-designed, rotational grazing treatment (RG) on density and kinds of cattle trails. Density of cattle trails in the RG treatment was compared to those in heavy continuous (HC), moderate continuous (MC), and deferred rotation (DR) treatments at 4 distances from water. There were no differences among the HC, MC, and DR treatments in density of trails. Trail densities ranged from 14/km near water sources to 9/km at the far end of the pastures. This compares to the RG treatment where trail densities ranged from 164/km near the cell center to 24/km at the far end of the paddock. The effect of increasing the RG treatment from 14 to 42 paddocks was also investigated. Subdivision of paddocks increased trail densities near the center from 32/km to 57/km with no increase noted at the far ends of the paddocks. It is concluded that implementation of a cell-designed, RG system will cause a significant increase in density and number of cattle trails particularly near the cell center.
    • Effects of Soil-Surface Morphology on Emergence and Survival of Seedlings in Big Sagebrush Communities

      Eckert, R. E.; Peterson, F. F.; Meurisse, M. S.; Stephens, J. L. (Society for Range Management, 1986-09-01)
      Various kinds of soil-surface microsites occur on loess-mantled Aridisols in central and northern Nevada. This study evaluates the potential of trampled and untrampled microsites to influence natural revegetation and either secondary succession or retrogression. Microsites present on different soil surfaces included the litter- and moss-covered Type I surface that occurs under the shrub canopy; the trench-like cracks and pinnacled polygons of the Type II surface that occur adjacent to the Type I surface; and the narrow cracks and smooth polygons with crusted, vesicular structure of the Type III surface that occurs in the interspaces between shrubs. Emergence and survival of Wyoming big sagebrush generally were greatest on the Type I and III surfaces, in the untrampled crack microsite of the Type III surface, and on the heavily trampled polygon microsite of the Type III surface. Emergence and survival of perennial grasses generally were greatest on the untrampled Type I surface, in the untrampled trench microsite of the Type II surface, and on moderately trampled trench and pinnacle microsites of the Type II surface. Emergence of annual and perennial forbs generally was greatest on untrampled trench and crack microsites of the Type II and III soil surfaces. Heavy trampling of trench and crack microsites reduced the emergence of perennial grasses, and both moderate and heavy trampling reduced the emergence of annual and perennial forbs. The potential for secondary succession would appear to be greatest where Types I and II surfaces and associated microsites predominate on a site and when trampling is moderate or absent. The potential for retrogression would appear to be greatest where the Type III surface and associated microsites predominate and when trampling is heavy.
    • Field Evaluation of Five Grasses Grown on a Saline Soil

      Currie, P. O.; Hilken, T. O.; White, R. S. (Society for Range Management, 1986-09-01)
      Russian wildrye (Psathyrostachys juncea), Altai wildrye (Leymus angustus), creeping foxtail (Alopecurus arundinaceus), and 2 forms of a bluebunch wheatgrass (Pseuduroegneria spicata) × quackgrass (Elytrigia repens) hybrid (RS-1 and RS-2) were evaluated in 1983 and 1984 for their suitability as forage for beef cattle. Hybrid selections produced 5,554 kg/ha of forage and their yields in 1983 were significantly more than those from the 2 wildryes and creeping foxtail that averaged 2,810 and 4,292 kg/ha, respectively. In 1984, there was not a significant difference among yields for the 5 grasses, but there was a significant increase in yield from 1983 for the 2 wildryes and creeping foxtail. Percent crude protein averaged 16% in the wildryes and 12.5% in the 2 hybrids and creeping foxtail in 1983. However, percent phosphorus averaged .40% in the creeping foxtail and .30% in the hybrids. In 1984, percent crude protein and phosphorus for all 5 grasses were lower than in 1983, but trends were similar. All 5 grasses exceeded the NRC crude protein and phosphorous requirement for a 500-kg lactating cow in 1983. In 1984, only the creeping foxtail and RS-1 hybrid exceeded the phosphorous requirement. In vitro organic matter digestibility averaged 64% in the ryegrasses and 54% in the hybrids for both years. In 1983, all 5 grasses exceeded the metabolizable energy requirement of a lactating 500-kg cow. Based on calculated nutritional index, Russian wildrye and Altai wildrye ranked 1 and 2 with the creeping foxtail and RS-2 hybrid ranking 4 and 5, respectively, in 1983. In 1984, Russian wildrye and the creeping foxtail ranked 1 and 2, and the RS-1 hybrid and RS-2 hybrid ranked 4 and 5.
    • Herbicide Conversion of a Sand Shinnery Oak (Quercus Havardii) Community: Effects on Biomass

      Sears, W. E.; Britton, C. M.; Wester, D. B.; Pettit, R. D. (Society for Range Management, 1986-09-01)
      Seasonal biomass dynamics were documented in an undisturbed sand shinnery oak (Quercus havardii) community and adjacent areas treated with tebuthiuron 3 years and 6 years prior to sampling. Biomass was measured for above-ground and below-ground compartments during growth initiation, peak standing crop, and winter dormancy in 1981. Total biomass showed little change on plots treated 3 years prior to sampling compared to the untreated oak plot. However, there was a decrease in total biomass on the 6-year plot compared to the other 2 treatments. Above-ground biomass decreased on both treated sites compared to the untreated plot reflecting oak death and decomposition.. Above-ground herbaceous material increased approximately 6-fold on both treated sites compared to the untreated plot. Oak root biomass decreased 12% at 3 years and 37% at 6 years following treatment. Herbaceous root biomass increased 3-fold on the 3-year-old treatment compared to the untreated oak community and was twice as much on the 6-year-old treatment compared to the untreated site. Distribution of herbaceous roots by soil depth was altered by treatment with a higher percentage of roots on the surface 30 cm on the treated sites compared to the untreated sites.
    • Herbicide Conversion of a Sand Shinnery Oak (Quercus Havardii) Community: Effects on Nitrogen

      Sears, W. E.; Britton, C. M.; Wester, D. B.; Pettit, R. D. (Society for Range Management, 1986-09-01)
      Seasonal nitrogen dynamics were documented in an undisturbed sand shinnery oak (Quercus havardii) community and in similar areas treated with tebuthiuron 3 years and 6 years prior to sampling in 1981. Percent nitrogen was determined for above- and below-ground biomass compartments and for the soil by depth using semimicro Kjeldahl analyses. Total nitrogen by weight in the ecosystem showed no change from the untreated rangeland to the 3-year-old treatment but was 14% higher on the 6-year-old treatment than on the control. Less nitrogen occurred in oak biomass compartments on the treated plots than on the control and more nitrogen occurred in the herbaceous compartments on the treated plots than on the control. Nitrogen (%) was similar for all compartments on the untreated and 3-year treatments but was slightly higher for all compartments on the 6-year-old treatment than on the other 2 sites. Soil nitrogen was slightly higher (3%) on the 3-year-old treatment than on the control and was 16% greater on the 6-year-old treatment than on the untreated rangeland.
    • Influence of Breed on Forage Intake of Range Beef Cows

      Kronberg, S. L.; Havstad, K. M.; Ayers, E. L.; Doornbos, D. E. (Society for Range Management, 1986-09-01)
      We estimated forage intake of Hereford (HH) and 75% Simmental-25% Hereford (3S1H) cows grazing in northcentral Montana during the summer grazing season of 1982. Cows ranged freely over a 81-ha pasture of rough fescue (Festuca scabrella)-dominated rangeland. Intake was estimated for 6 lactating (March calved) and 6 nonlactating cows of each breed type in June, July, August, and September, 1982. Fecal output of dry cows was measured with total fecal collections and was also estimated with the chromic oxide dilution technique. Only the chromic oxide technique was used for lactating cows. Three to 4 esophageal-fistulated cows of each breed type were used for collection of dietary material suitable for in vitro digestibility analysis. Organic matter intake (as a percentage of body weight per day, %BW/D) of nonlactating HH and 3S1H cows did not differ (P is greater than or equal to 10), averaging 1.3% BW/d (using total fecal collection estimates). Chromic oxide derived forage intake estimates were 15% higher (P<.10) than total fecal collection estimates. Breeds responded similarly (P4 1/4.10) to both fecal output estimation techniques. Forage intake estimates for lactating cows were adjusted for this overestimation, and lactating 3S1H cows consumed more (P<.10) forage than lactating HH cows (1.9 vs. 1.7% BW/d, and 10.9 vs. 7.8 kg/d, respectively).
    • Management of Subterranean Clover in Pine Forested Range

      Johnson, M. K.; Davis, L. G.; Ribbeck, K. F.; Render, J. H.; Pearson, H. A. (Society for Range Management, 1986-09-01)
      Subterranean clover (Trifolium subterraneum) is a cool-season forage legume that can be grown in the southeastern United States. Available varieties grow best on well-drained sites and tolerate acid soil conditions producing adequate forage without addition of lime if soil pH is 4.8 or higher. However, at least during the first few years, annual applications of at least 50 kg/ha of P2O5 and K2O are needed to maintain good production. In addition, summer growth of competing vegetation must be removed annually in late August or early September by heavy livetock grazing, use of herbicide, or close mowing. Unlike other clovers, subterranean will reseed even if heavily grazed during the flowering stage. Initial establishment under pine timber in the Southeast can be achieved by removal of hardwoods, prescribed burning, and broadcasting freshly inoculated seed on top of the soil in late October or early November when the soil surface is wet. Production of adequate forage before mid-winter remains a problem, especially if unregulated use by deer is heavy.
    • Methods of Enhancing Germination of Anacua Seeds

      Fulbright, T. E.; Flenniken, K. S.; Waggerman, G. L. (Society for Range Management, 1986-09-01)
      Seed dormancy hampers establishment of anacua [Ehretia anacua (Teran & Berl.) I.M. Johnst.] in plantings for wildlife. We evaluated methods of enhancing anacua germination and causes of dormancy. Seeds were (1) scarified with 2.9 mol liter-1 H2O2 or 0.71 mol liter-1 NaOCl for 10, 20, or 30 minutes, or concentrated (18.0 mol liter-1) H2SO4 for 15, 30, 60, or 120 minutes; (2) rinsed with water for 12, 24, 36, and 48 hours; (3) treated with 0.1, 1.4, 2.9, and 4.3 mmol liter-1 gibberellic acid (GA); (4) treated with 0.02 mol liter-1 KNO3; (5) treated with dry heat (130 degrees C) for 3, 6, 9, 12, and 15 minutes, (6) mechanically scarified; and (7) moist prechilled at 3 and 7 degrees C for 2 or 4 weeks. Seeds were germinated in controlled environment chambers at 30 degrees C. Germination was not enhanced by chemical scarification or rinsing. GA (1.4 mmol liter-1) increased germination from 35% for controls to 61%. Mechanical scarification and dry heat enhanced germination of highly dormant seeds only. A 2-week moist prechill at 3 degrees C increased germination of intact seeds from 6% for controls to 36%. Percent and rate of germination were similar among seed sources. Apparent afterripening requirements limited germination at 2 months after harvest to 3%. This requirement gradually broke down until at 8 months after harvest, germination had increased to 40%. Our results indicated that treatment with 1.4 mmol liter-1 GA or higher concentrations, moist prechilling for 2 weeks at 3 degrees C, and storage for 8 months will increase germination of dormant anacua seeds.
    • Nutritive Value of Forages on Sandy Soils As Affected by Tebuthiuron

      Biondini, M.; Pettit, R. D.; Jones, V. (Society for Range Management, 1986-09-01)
      Tebuthiuron, [N-(5-1,1-dimethyethyl-l1,3,4-thiadiazol-2-yl)-N,N′-dimethylurea], a root-absorbed pelleted herbicide, was broadcast onto sand shinnery oak (Quercus havardii) rangeland in west Texas, May 1978. Green herbage of the dominant grasses was assayed for nitrogen (N), phosphorus (P), 24-hr in vitro dry matter digestibility (24 hr-IVDMD), and cell wall content (CWC) on 3 dates in both 1978 and 1979. In 1978, tebuthiuron at 0.4 kg/ha or above improved quality of the major forages. Crude protein was up to 28% higher in treated plants the year of application. The P content ranged from 0.08 to 0.12% over all sampling dates. Digestibility increased slightly while no difference was found in CWC. Tebuthiuron had no effect on forage quality the year after application. The most consistent change in parameters measured was water content of little bluestem (Schizachyrium scoparium). Untreated plants averaged 38% water throughout the growing season, while treated plants contained 50% water. Major benefits of killing oak are increased forage availability and not yet resolved palatability factors.
    • Photosynthetic Characteristics of Crested Wheatgrass and Bluebunch Wheatgrass

      Nowak, R. S.; Caldwell, M. M. (Society for Range Management, 1986-09-01)
      Light and temperature dependencies for net photosynthesis and stomatal conductance were generally very similar between foliage on crested wheatgrass (Agropyron desertorum (Fisch. ex Link) Schult.) plants and that on bluebunch wheatgrass (A. spicatum (Pursh) Scribn. and Smith) plants. The similarity of these gas exchange characteristics between the 2 bunchgrass species was true for foliage on unclipped plants as well as on partially defoliated plants. However, light and temperature dependencies of senescing leaf blades that were exserted in late-spring were significantly different for unclipped plants of these 2 species. Photosynthetic rates and stomatal conductances of senescent late-season blades on bluebunch wheatgrass plants were greater than those on crested wheatgrass plants at light intensities greater than 0.8 mmol photons m-2 s-1 (photosynthetic photon flux density) and at all foliage temperatures between 18 degrees C and 41 degrees C. These greater photosynthetic rates and stomatal conductances do not mean that bluebunch wheatgrass tillers gained substantially more carbon or lost substantially more water than crested wheatgrass tillers. If both the photosynthetic area composition of tillers and the environmental conditions of the northern Utah study site were considered, carbon gain and water loss for individual bluebunch wheatgrass tillers would be very similar to those for individual crested wheatgrass tillers despite the significantly different responses to light and temperature during mid-summer.
    • Pollination Requirements of Cicer Milkvetch, Astragalus cicer L.

      Richards, K. W. (Society for Range Management, 1986-09-01)
      The effect of bee pollination on seed yield of cicer milkvetch, Astragalus cicer L., has not been reported previously for Alberta. The effect of insect pollination was determined by comparing seed yields of open-pollinated and pollinator-excluded plants. It was determined that cicer milk vetch must be cross-pollinated for optimum seed yield, although 1.8% of the flowers from pollinator-excluded plant produced pods and seeds. Flowers pollinated within the first 4 days after opening produced more seeds per pod than did flowers pollinated after the fourth day. The actual seed yields with open pollination at 2 locations were only 25.3 and 11.7% of the mean potential seed yields.
    • Range Management and Scenic Beauty as Perceived by Dispersed Recreationists

      Sanderson, H. R.; Meganck, R. A.; Gibbs, K. C. (Society for Range Management, 1986-09-01)
      Land management agencies have developed considerable interest in the visual impacts of intensive range management. This study was designed to determine the impact of range management activities on dispersed recreationists and their concept of scenic beauty. We analyzed the ratings by 241 dispersed recreationists of selected range management activities and ecosystems on the Malheur National Forest in eastern Oregon during the summer of 1978. Features significantly related to dispersed recreationists' reactions to range management activities were primary recreational activity, place of residence, understanding of the purpose of a National Forest, and number of prior visits to the Malheur National Forest. Respondents reacted favorably to the range management activities examined. A majority, however, indicated that their use of recreational areas would be altered if management intensity increased or became more apparent.
    • Relation Between Ecological-Range Condition and Proportion of Soil-Surface Types

      Eckert, R. E.; Peterson, F. F.; Belton, J. T. (Society for Range Management, 1986-09-01)
      Different kinds of A-horizon soil-surface types occur on loessmantled xerollic Orthids and Argids in the Intermountain area. Four soil-surface types were identified on sites with potential vegetation of Wyoming big sagebrush [Artemisia tridentata wyomingensis Beetle] and Thurber needlegrass [Stipa thurberiana Piper]. These surfaces occupy different microtopographic positions and have different morphologies and chemical and physical properties. This study relates differences in the cover of these soil-surface types to ecological-range condition on sites of similar potential. Proportion of the surface type found under shrub or bunchgrass cover varies with range condition. More of the surface associated with shrub cover is found on low condition sites because of greater sagebrush cover. More of the surface associated with bunchgrass cover is found on high condition sites because of greater grass cover. Proportion of the surface types found in the interspace between shrubs also varies with range condition. High condition sites have a greater cover of the soil surface associated with bunchgrass cover and of the soil surface with cryptogam-stabilized microrelief. Conversely, low condition sites have essentially none of the soil surface associated with bunchgrass cover but a large amount of the soil surface with little microrelief. Results are interpreted in terms of watershed stability and natural revegetation potential.
    • Technical Notes: A Rumen Cannula for Small Ruminants

      Miller, W. H.; Maltby, M. (Society for Range Management, 1986-09-01)
      A ridged rumen cannula made from polyvinyl chloride pipe fittings and plexi-glass at a material's cost of $2.50, is ideally suited for use on small ruminants. Its advantages over other rumen cannula designs include its simple construction, maintenance, ease of sampling, and immediate availability for use following surgical installation. A threaded outer adjustable washer provides a means of lightly tightening the cannula to the body wall thus preventing leakage and dislodgment of the cannula. The cannula can be adapted for various small ruminants by varying the size of the pipe fittings used to construct the cannula.
    • The Botanical Composition of the Diet of Free-Ranging Cattle on an Alpine Range in Australia

      Rees, H. Van.; Holmes, J. H. G. (Society for Range Management, 1986-09-01)
      Five oesophageal-fistulated steers were used to determine the botanical composition, on a quantitative basis, of the diet of freeranging cattle on an alpine range in Victoria, Australia. The steers primarily selected 4 grass species, 3 sedges and 1 rush, 6 forbs and 3 shrub species. Species selection changed significantly with seasonal advance. Generally grass species were preferred early in the grazing season, shrubs in the middle of the season and forbs towards the end of the season. The main species identified in the diet which should be used as indicator species of range condition are: alpine star-bush (Asterolasia trymalioides F. Muell.), snow daisy (Celmisia asteliifolia J.D. Hook), alpine grevillea (Grevillea australis R. Br.), scaly buttons (Leptorhynchos squamatus (Labill.) Less.) and soft snow grass (Poa hiemata Vick.).