• Comparison of Heifer Weight Gains and Forage Quality for Continuous and Short-duration Grazing Systems

      Jung, H. G.; Rice, R. W.; Koong, L. J. (Society for Range Management, 1985-03-01)
      A study of animal performance and forage quality under continuous and short-duration grazing (SDG) systems was conducted with post-weaning heifer calves on smooth bromegrass (Bromus inermis) pasture for 2 years. There were 8 paddocks for each SDG cell. The animals were on pasture from early May through the middle of August in both years. Heifers assigned to the SDG system were moved among the rotational paddocks approximately every 2.5 days. In 1982, the grazing treatments were stocked at equal levels (2.9 animals/ha). The stocking rate was increased to 3.8 animals/ha on the SDG treatment in 1983, while the continuous system remained at 2.9 animals/ha. Animals were weighed and forage samples were collected at the completion of each rotation cycle. Average daily gain (ADG) was similar (continuous 0.48 kg/d vs. SDG 0.47 kg/d, P>.05) in 1982 when both systems were stocked equally. Available forage tended to be greater under the SDG system (3,141 vs. 3,786 kg/ha), but this difference was not significant. Forage quality did not differ (P>.05) between the grazing systems but did decline significantly in both systems during the grazing season. Individual paddocks of the SDG system did not differ significantly in forage quality. In 1983, ADG was similar for both grazing systems (0.56 and 0.52 kg/d, P>.05) and available forage also was similar (2,551 vs. 2,159 kg/ha). Crude protein content of the forage tended to be greater for the SDG system (7.9 vs. 8.5%, P<.05) in 1983. In vitro digestibility and crude protein content were lower, and cellulose and lignin concentrations were higher in forage from paddocks grazed later in the rotation sequence in 1983. The SDG system increased available forage when stocking rates were equal for the grazing systems, and this forage was effectively utilized at a higher stocking rate for the SDG system to produce more grain per ha (165.6 vs. 205.6 kg/ha) without sacrificing individual performance.
    • Discing and Seeding Effects on Sod Bound Mixed Prairie

      Hart, M.; Waller, S. S.; Lowry, S. R.; Gates, R. N. (Society for Range Management, 1985-03-01)
      A silty range site (720 mm average annual precipitation) in the Mixed Prairie of south-central Nebraska dominated by Kentucky bluegrass (Poa pratensis L.), blue grama [Bouteloua gracilis (H.B.K.) Lag.], western wheatgrass (Agropyron smithii Rydb.), and buffalograss [Buchole dactyloides (Nutt.) Englem.] was protected from grazing, disced, seeded and/or treated with glyphosate to increase tall and midgrasses. Discing did not stimulate western wheatgrass yield or cover. After 2 growing seasons, yields and cover were similar on untreated and disced areas. However, species composition data indicated a treatment × year interaction between the second and third growing season for proportion of warm-season shortgrass sod to dominant cool-season vegetation. Warm-season shortgrasses increased on the disced area and decreased on the control during that period. Lo-till sod-seeding using glyphosate [N-(phosphonomethyl glycine)] as a sod suppressant provided rapid establishment of desirable warm-season grasses: big bluestem (Andropogon gerardii Vitman), indiangrass [Sorghastrum nutans (L.) Nash], switchgrass (Panicum virgatum L.) and sideoats grama [Bouteloua curtipendula (Michx.) Torr.]. Seeding with a rangeland drill into a disced area or an area disced and then sprayed with glyphosate resulted in slower stand establishment compared to sod seeding. All seeding treatments had similar stand frequency during the third growing season and similar yield at the end of the fourth growing season. All seeding methods provided adequate stands.
    • Effects of Forage Availability on Grazing Behavior of Heifers

      Scarnecchia, D. L.; Nastis, A. S.; Malechek, J. C. (Society for Range Management, 1985-03-01)
      Effects of decreasing availability of crested wheatgrass (Agropyron desertorum and Agropyron cristatum) on grazing time and biting rate of Angus heifers were investigated. In the first year of the study, as standing crop decreased from 474 to 170 kg dry matter/ha, grazing time increased from 517 to 203 min/day, while biting rate increased from 56 to 64 bites/min. In the second year, as standing crop decreased from 919 to 144 kg dry matter/ha, grazing time increased from 380 to 656 min/day while biting rate increased from 37 to 50 bites/min. Grazing times were similar to those reported in the literature for pastures having much higher levels of available forage. Although grazing times may be correlated with available forage, comparison of grazing times under different pasture conditions are not meaningful unless considered along with other forage and animal factors. On crested wheatgrass pastures, maximum biting rates occurred at lower levels of available forage than reported on tropical pastures.
    • Effects of Regulated Water Flows on Regeneration of Fremont Cottonwood

      Fenner, P.; Brady, W. W.; Patton, D. R. (Society for Range Management, 1985-03-01)
      The reduction in extent of riparian forests in the southwestern United States has been a topic of recent concern. The effect of dams on downstream river flow and the consequent modification of the riparian habitat was studied along the lower Salt River in central Arizona. Dams were found to change the magnitude of river flows and change the seasonal timing of flows in such a way that the habitat appeared less adapted for regeneration of Populus fremontii. Modification of river flow patterns, therefore, appears likely to have been a significant factor causing change in vegetation along the Salt River.
    • Effects of Sulfur Fertilization on Productivity and Botanical Composition of California Annual Grassland

      Caldwell, R. M.; Menke, J. W.; Duncan, D. A. (Society for Range Management, 1985-03-01)
      Changes in botanical composition and productivity of total herbage and 14 categories of annual range plants caused by elemental sulfur fertilization, range site, and precipitation were studied. Total herbage production on the wetter and more fertile swale sites was not affected by sulfur fertilization, but production on adjacent open upland and rocky, brushy upland sites usually increased with added S. Herbage production increased 28% or 1,400 kg/ha on fertilized open upland sites and 51% or 1,800 kg/ha on fertilized rocky, brushy upland sites during the wettest year sampled. Over the 3 years sampled, the most desirable grass, soft chess, averaged 68, 22, and 66% higher production (438, 287, and 388 kg/ha increases, respectively) on fertilized versus control range units for swale, open upland, and rocky, brushy upland range sites, respectively. Likewise, the less desirable but important early-forage species, ripgut brome, increased 164% or 544 kg/ha on swales and 205% or 437 kg/ha on rocky, brushy uplands with fertilization; only a 16% increase or 98 kg/ha occurred on open upland sites. Grass responses were offset by decreased forb production, while the proportion of legumes remained nearly the same. Upland sites benefited from sulfur fertilization by exhibiting both increased clover and other legume production in the wettest year. Filaree was unaffected by sulfur fertilization.
    • Emergence and Establishment of Basin Wild-Rye and Tall Wheatgrass in Relation to Moisture and Salinity

      Roundy, B. A. (Society for Range Management, 1985-03-01)
      Many saline, arid rangelands in the Great Basin once dominated by basin wildrye (Elymus cinereus Scribn. & Merr.) could again be highly productive following brush control and seeding of adapted species. The effects of spring precipitation and soil salinity on emergence and establishment of Jose tall wheatgrass [Agropyron elongatum (Host) Beauv. 'Jose'] and Magnar, a selected cultivar of basin wildrye, were compared in central Nevada. Both species were seeded in circular plots on a nonsaline and a moderately saline soil (electrical conductivity of the saturation extract, ECe, of 7.0 ds m-1) and irrigated to simulate a gradient in spring precipitation. Magnar basin wildrye required higher and more frequent irrigation and precipitation in April through June to produce an acceptable stand of seedlings (at least 2 seedlings per meter of row) on the moderately saline soil than on the nonsaline soil. Jose tall wheatgrass produced acceptable seedling stands without irrigation and excellent stands (6 seedlings per meter of row) with irrigation on both soils following a wet winter and during a dry spring. Although mature basin wildrye is well adapted to many saline, arid soils, it definitely will require supplemental irrigation to establish from seed. Tall wheatgrass is more salt tolerant and less sensitive to plant water stress at the seedling stage than basin wildrye, so it is more likely to establish on saline, arid soils without irrigation. However, mature tall wheatgrass may not persist in areas that receive less than 30 cm annual precipitation. Until more drought and salt-tolerant plant materials are available, saline, arid soils should not be seeded without supplemental irrigation.
    • Estimation of Fecal Output and Particulate Passage Rate with a Pulse Dose of Ytterbium-Labeled Forage

      Krysl, L. J.; McCollum, F. T.; Galyean, M. L. (Society for Range Management, 1985-03-01)
      Twelve rumen-cannulated lambs (avg. wt. 40 kg), fed long-stem alfalfa or prairie hay in a crossover design (two, 15-day periods) were used to compare estimates of fecal output from a pulse dose of ytterbium (Yb)-labeled forage and fecal collection bags. Estimates of fecal output (g/day) with Yb-labeled forages were not different (P>.05) from total collection values for lambs fed either alfalfa or prairie hay. Fecal output from a pulse dose of Yb was 100 +/- 2% of total collection for lambs fed alfalfa and 103 +/- 3% for lambs fed prairie hay. Particulate passage from the rumen was faster (P<.01) in lambs fed alfalfa (7.0%/hr) then in lambs fed prairie hay (3.9%/hr). A pulse dose of Yb-labeled hay appears to prove reliable estimates of fecal output as well as passage rate estimates, but validation of techniques in free-grazing ruminants is needed.
    • Germination Responses of Greasewood (Sarcobatus vermiculatus) to Temperature, Water Potential and Specific Ions

      Romo, J. T.; Eddleman, L. E. (Society for Range Management, 1985-03-01)
      Seeds of greasewood (Sarcobatus vermiculatus (Hook.) Torr.) were germinated at 5 degrees to 40 degrees C in 5-degree increments to determine temperature response. Seeds were also germinated in solutions of polyethylene glycol 6,000 (PEG), NaCl, and Na2 SO4, each at osmotic potentials of 0 to -4.2 MPa in -0.3 MPa decrements at 10, 20 and 30 degrees C to determine moisture stress, specific ion, and temperature interaction. Germination was high at all temperatures, 5 degrees C through 25 degrees C being optimal. A direct linear relationship existed between total germination and osmotic potential of each solution at each temperature. Mean germination at 30 degrees C was significantly different for each osmotica with NaCl highest and PEG lowest. Mean germination at 10 degrees C and 20 degrees was not different within osmotica; however, total germination was significantly lower in PEG than in NaCl and Na2SO4, indicating the difference between macromolecular PEG and ions (NA+, Cl-, and SO4=). Significant difference was observed in the coefficient of rate of germination between ions of Cl- and SO4=, with SO4= being more stressful.
    • Germination, Forage Yield, and Seed Production of American Sloughgrass (Beckmannia syzigachne)

      Boe, A.; Wynia, R. (Society for Range Management, 1985-03-01)
      Germination, forage yield, and seed production characteristics were studied in American sloughgrass (Beckmannia syzigachne (Steud.) Fern.), a valuable wetland forage species in the northwestern and northcentral states. Germination of field-collected caryopses from northeastern Montana, stored at 7 degrees C for 60 days post-harvest, was significantly (P<0.05) higher under alternating temperatures (7 degrees C for 15 h and 21 degrees C for 9 h in each 24-h period) than at constant 21 degrees C. Germination percentages greater than 60% were found for freshly harvested greenhouse-produced spikelets and caryopses after 14 days in complete darkness, and no significant differences were detected between complete darkness and 15 h dark/9 h light treatments under alternating temperatures. Greenhouse-produced caryopses were significantly heavier and exhibited significantly higher germination than caryopses from field collections. A Montana field collection and a seed increase of that collection significantly (P<0.05) outyielded a local South Dakota collection for both forage and seed at Brookings, South Dakota. Overall mean dry matter forage and mature seed yields were 2,700 and 540 kg/ha, respectively. Forage yields at early-head of the seed increase population planted at 15, 18, and 21 kg/ha were not significantly different and had an overall mean of 5,000 kg/ha. These preliminary data indicate that the potential of B. syzigachne as a cultivated forage for cropland depressions in the Northern Great Plains does not appear to be limited by complex germination requirements, low forage yield, or weak seed production.
    • Leafy Spurge Control with Herbicides in North Dakota: 20-Year Summary

      Lym, R. G.; Messersmith, C. G. (Society for Range Management, 1985-03-01)
      Leafy spurge (Euphorbia esula L.) control by herbicides can vary from year to year due to changing environmental conditions. Data from leafy spurge control experimental and demonstrational plots with 2,4-D[(2,4-dichlorophenoxy)acetic acid], dicamba (3,6-dichloro-o-anisic acid), picloram (4-amino-3,5,6-trichloropicolinic acid) and glyphosate [N-(phosphonomethyl)glycine] were combined from 1963 through 1982. The amine and ester formulations of 2,4-D provided similar leafy spurge control. 2,4-D at rates up to 4.5 kg/ha provided less than 40% control after 1 year, and annual (spring or fall) or biannual (spring and fall) 2,4-D applications did not increase leafy spurge control. Dicamba was most effective as a liquid formulation when spring applied and as a granular formulation when fall applied. Dicamba at 9.0 kg/ha was required for satisfactory leafy spurge control for 1 year. Picloram at 2.2 kg/ha gave over 90% control of leafy spurge for 2 growing seasons regardless of formulation or time of application. Synergistic weed control was observed when 2,4-D at 1.1 kg/ha or less was applied with dicamba or picloram at 0.6 kg/ha or less. These synergistic herbicide combinations are economical on many pasture and rangeland sites infested with leafy spurge. Fall-applied glyphosate at 0.8 kg/ha or more gave good control of established leafy spurge for 1 year in shelterbelts and as a spot treatment.
    • Particle Size Changes in Rumens of Cattle Grazing Kansas Flint Hills Range

      Forwood, J. R.; Owensby, C. E.; Towne, G. (Society for Range Management, 1985-03-01)
      A ruminally fistulated Hereford steer and heifer grazing Kansas Flint Hills range were used with the objective of determining forage particle breakdown and distribution in different rumen sites over several hours post feeding during seasons of differing forage quality. During the first year, samples were taken after an overnight fast from 3 rumen sites and from feces early on the sample morning (AM sample). The cattle were fed and sampled again 12 hours later (PM sample). During year two, the cattle were sampled immediately as they came from the native pasture (PRE sample) in addition to the 2 other sample times. Samples were wet-sieved through a series of 5 screens to separate particle sizes. Material from each screen was dried, weighed and expressed as a percentage of the total of all screens. In the rumen, relative amounts of coarse particles generally decreased while amounts of smaller particles generally increased with advancing season. Forage maturity had similar effects on fecal particle sizes. Particles in the feces were more uniform in size than particles in the rumen.
    • Performance and Phosphorus Status of Range Cows with and without Phosphorus Supplementation

      Judkins, M. B.; Wallace, J. D.; Parker, E. E.; Wright, J. D. (Society for Range Management, 1985-03-01)
      Performance and phosphorus (P) status were studied in 2 groups of range cows, one of which had free access to salt alone (control) and the other to a mineral mix (P-supplemented). The mineral mix contained 50% dicalcium phosphate, 45% salt, and 5% cottonseed meal. Performance traits (birth date, calving interval, weaning weight, suckling gain, and percent calf crop) were compared over 5 years (1979-83), one of which was considered a drought year (1980). Cows involved in the study received no supplemental protein or energy during the experiment. Lack of P supplementation had a detrimental effect on cow performance only when coupled with the effects of drought. This apparent combined effect delayed postpartum estrus in control cows during the 1980 drought, thus causing them to calve later (7 April vs. 11 February; P<.05) and wean lighter (226 vs. 253 kg; P<.05) calves in 1981 as compared to P-supplemented cows. Percent calf crop did not differ (P>.05) between the 2 groups during any year of the study, although in both groups, this trait was considerably lower in 1981 than in other years because of the 1980 drought. These results suggest that rainfall or P supplementation before and during the breeding season may be critical in maintaining early calving dates and heavier weaning weights but, even with P supplementation, lower conception rates may occur under drought conditions. Phosphorus status of cows was estimated from fecal, saliva, and rib bone biopsy samples collected at 6 intervals from April 1981 to January 1982. Fecal P varied (P<.05) among sampling dates and was higher (P<.05) for P supplemented cows than for control cows when averaged over sampling dates. Levels of fecal P were higher (P<.05) during the period of active forage growth than during dormancy. Salivary P peaked concurrently with fecal P; however, across sampling dates, response to supplemental P was inconsistent as evidenced by a treatment × date interaction (P<.05). During lactation, bone P levels were higher (P<.10) in P supplemented cows than in control cows. After lactation, bone P did not differ (P>.10) between groups and was higher (P<.001) than during lactation, which indicates bone P levels can be replenished following lactation without P supplementation.
    • President's Address

      Schuster, Joseph L. (Society for Range Management, 1985-03-01)
    • Recovery of Sagebrush-Grass Vegetation Following Wildfire

      West, N. E.; Hassan, M. A. (Society for Range Management, 1985-03-01)
      Most studies of the impacts of fire in sagebrush-grass vegetation in the Great basin have involved recovery on sites seriously depleted of native perennial bunchgrasses. The usual recommendation is to promptly seed such areas artificially. This is costly, not always successful, and if unnecessary, could produce no more than a natural recovery. The natural recovery of a good condition sagebrush-grass site in central Utah was monitored for 2 years after a mid-summer wildfire. Total plant cover 1 year after the fire was similar to that before the fire and on unburned controls. Annual herbaceous growth 1 year later was almost twice that before the fire. Most of the plant growth the first year was due to cheatgrass (Bromus tectorum). By the second year after fire, however, the perennial bunchgrasses had cover and production levels near those recorded prior to the burn. Two years after the fire, total grazable forage was 2.5 times that before the fire. Total precipitation, however, had been higher than average both years. Sagebrush-grass sites in good condition may be improved for cattle production with a few years of livestock exclusion following wildfire. Prescribed or controlled burns would probably be appropriate on similar high condition rangelands if cattle grazing is the dominant use and conflicts with wildfire are minor.
    • Rough Fescue Response to Season and Intensity of Defoliation

      McLean, A.; Wikeem, S. (Society for Range Management, 1985-03-01)
      Rough fescue (Festuca scabrella Torr.) was subjected to 10 clipping regimes which varied in time or intensity of defoliation. The experiment was repeated at 2 sites for 3 consecutive years. Plant survival and vigor were evaluated the summer following defoliation. Clipping treatments involving weekly defoliation to a 5-cm stubble height from mid May to late June resulted in the greatest injury. Reduced injury occurred when clipping ceased in May or when 10 or 15 cm of herbage was retained. Season long defoliation to 20 cm or clipping only in the fall caused no apparent damage. Cutting in the fall plus spring resulted in greater injury than spring clipping alone on plants clipped from mid May to late June but a fall clipping effect was not observed consistently on plants clipped in May plus fall.
    • Seasonal Nutrient Estimates of Mule Deer Diets in the Texas Panhandle

      Sowell, B. F.; Koerth, B. H.; Bryant, F. C. (Society for Range Management, 1985-03-01)
      Botanical composition and estimated seasonal nutrient quality of mule deer (Odocoileus hemionus) diets from the Canadian River and Clarendon areas of the Texas Panhandle were determined from 1979 to 1980. Deer from the Canadian River area consumed annually 62% browse, 34% forbs, 1% grasses, and 3% unknowns. Deer from the Clarendon area averaged 56% browse, 28% forbs, 11% grasses, and 5% unknowns annually. Deer consumed more grass at Clarendon because they had access to cultivated small grains, primarily winter wheat and rye. Annual deer diets from the Canadian River area contained 8 +/- 1% crude protein (CP), 0.14 +/- .03% phosphorus (P), and 47 +/- 2% in vitro organic matter digestibility (IVOMD). Deer diets from the Clarendon area averaged 10 +/- 3% CP, 0.15 +/- .03% P, and 50 +/- 2% IVOMD annually. Higher nutrient quality of mule deer diets at Clarendon suggests cultivated small grains/legumes have excellent potential to enhance Texas Panhandle deer herds that normally subsist on a fair to poor nutritional plane.
    • Seasonal Trends in the Chemical Composition of Ten Range Plants in South Texas

      Meyer, M. W.; Brown, R. D. (Society for Range Management, 1985-03-01)
      The chemical composition of 10 range plants of dietary importance to cattle and white-tailed deer (Odocoileus virginianus) was determined on the Texas A&I University Range and Wildlife Research Pastures from October 1980-September 1981. Samples were analyzed for crude protein (CP), neutral detergent fiber (NDF), lignin, organic matter (OM), in vitro dry matter digestibility (IVDMD), phosphorus (P), and calcium (Ca) concentration. The grasses were lower (P<.05) in CP and Ca concentration than the non-grasses, while non-grasses had lower (P<.05) NDF content. On the basis of digestibility, fiber content, protein, and mineral concentration, forage quality was highest in the spring. Winter forage samples were of a higher quality than were late summer samples. Low phosphorus concentrations were common throughout the year.
    • Technical Notes: An Effective Fecal Harness for Free-grazing Goats

      Pfister, J. A. (Society for Range Management, 1985-03-01)
      A fecal harness for goats proved useful for total fecal collections under rigorous field conditions in dense brush. An important aspect of this fecal harness is that feeding mobility of goats is not impaired.
    • The Decline of the Angora Goat Industry in Three Texas Counties

      Schrivner, J. H. (Society for Range Management, 1985-03-01)
      One hundred three present and 104 past Angora goat producers in 3 Texas counties were questioned regarding the relative importance of factors contributing to the decline of the goat industry in Texas. While the distribution of past and present producers among herd-size, ownership, and age classes was similar, it differed with regard to kidding. More present producers attempted to reduce livestock losses by shed and shed/trap kidding and use of predator control and husbandry techniques. Present producers also reported fewer kids and adults killed by predators. Predation losses was the production-limitation factor of greatest concern to both present and past goat ranchers. Disease problems and concern over competition from the synthetic fiber industry were ranked second and third, respectively, by present producers whereas mohair prices were ranked second and shortage of shearers, disease problems, and competition from the synthetic fiber industry collectively were ranked third by past producers.