• 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.).
    • Use of the FW-1 Water Level Recorder for Control of Electrical Equipment

      Wilson, R. E.; Dolphin, A.; Simanton, J. R. (Society for Range Management, 1986-09-01)
      A simple, inexpensive, and positive on/off control device can be added to the FW-1 water level recorder for activation of electrical instrumention used in rangeland hydrologic investigations. The device utilizes existing FW-1 gearing and readily available brass and aluminum parts and can be modified to perform over a wide range of water stage heights.
    • Vegetation of Exclosures in Southwestern North Dakota

      Brand, M. D.; Goetz, H. (Society for Range Management, 1986-09-01)
      A 3-year study of the vegetation in 4 livestock exclosures was begun in 1976 in the mixed grass prairie of southwestern North Dakota. Three of the exclosures were established in 1937 and the fourth in 1938. The exclosures had greater graminoid leaf heights and greater mulch accumulations than the adjacent grazed plots; however, total yield and total belowground biomass were not significantly different between plots in 3 out of the 4 sites. The major difference between the exclosures and the adjacent grazed plots was species composition. The production of blue grama (Bouteloua gracilis (H.B.K.) Griffiths) was lower, and the production of thread-leaf sedge (Carex filifolia Nutt.) and another sedge (Carex heliophila Mack.) was greater in the exclosures than on the adjacent grazed plots. A summary by growth form also showed that the midgrass and tallgrass growth form category was more dominant in only 1 out of 4 exclosures. The interpretation of these data indicates that the potential for changes in growth form dominance and total yield due to management inputs must be evaluated on a site specific basis. Species composition also was a more reliable indicator of successional status than growth form dominance.
    • Vegetation Responses to Long-Term Sheep Grazing on Mountain Ranges

      Bowns, J. E.; Bagley, C. F. (Society for Range Management, 1986-09-01)
      Some high-elevation summer ranges in southwestern Utah are characterized by a dominance of grass and low-value forbs. A reference area of forb dominance provides a striking contrast to these grass ranges. The reference area has a greater number of total species and a greater number of forbs. Production (above-ground live biomass) is nearly 2 times as great in the reference area as in the surrounding pastures. Production of desirable species in the reference area is greater than the production of desirables, intermediates, and least desirables in the surrounding pastures. It is suggested that the grass dominance on these ranges is due to a long and persistent history of exclusive sheep grazing.
    • Viewpoint: Animal-Unit Equivalents Should Be Weighted by Dietary Differences

      Hobbs, N. T.; Carpenter, L. H. (Society for Range Management, 1986-09-01)
    • Woody Plants Reestablishment in Modified Pinyon-Juniper Woodlands, New Mexico

      Severson, K. E. (Society for Range Management, 1986-09-01)
      Pinyon (Pinus edulis Engelm.), one-seed juniper (Juniperus monosperma (Engelm.) Sarg.), and alligator juniper (J. deppeana Steud.) woodlands in southwestern New Mexico were thinned, were pushed with bulldozers leaving slash in place, and were pushed and then slash piled and burned. There were no significant differences (P>0.05) in densities of these trees 13 and 18 years later between untreated (379 trees/ha) and thinned (489 trees/ha) plots or between pushed/left (67 trees/ha) and pushed/piled/burned plots (49 trees/ha). Differences between bulldozed treatments and untreated/thinned treatments were significant (P<0.05). Total shrubs, 75% of which were gray oak (Quercus grisea Liebm.) and hairy mountainmahogany (Cercocarpus breviflorus Gray), were significantly more abundant in untreated areas (672 shrubs/ha), than in any of the treatments. No differences were noted among treatments (493, 393, 329 shrubs/ha for thinned, pushed/left, and pushed/piled/burned, respectively). Rates of pinyon reestablishment increased slowly up to the mid-1960's (from 1.1 to 1.3 trees/ha/year) then accelerated to 10 to 13 trees/ha/year. Pinyon and juniper densities were about 120 trees/ha when reestablishment rates increased.