• Effects of Temperature and Presowing Treatments on Showy Menodora Seed Germination

      Fulbright, T. E.; Flenniken, K. S. (Society for Range Management, 1986-07-01)
      Low seed germination is a problem in establishment of showy menodora (Menodora longiflora Gray). Objectives of this study were to determine the effects of temperature, light, and presowing treatments on showy menodora germination. Scarified and untreated seeds were germinated at 5/15, 10/20, 15/25, 20/30, 25/35, and 30/40 degrees C (12 hour/12 hour) with 12 hours of light at the warmer temperature or complete darkness. Seeds were subjected to: (1) chemical scarification with concentrated (18.0 mol liter-1) H2 SO4, 2.9 mol liter-1 H2O2, or 0.7 mol liter-1 NaOCl, (2) a hot (80 degrees C) water soak, and (3) nicking with a razor blade. Percent germination and germination rate were highest at 20/30 degrees C. The highest percentage of abnormal seedlings occurred for mechanically scarified seeds at 5/15 degrees C. Light did not affect germination at 15/25, 20/30, and 30/40 degrees C, but enhanced germination at 5/15, 10/20, and 25/35 degrees C. Scarification enhanced percent germination and germination rate at all temperatures. At 20/30 degrees C, nicking seeds with a razor and a 3-minute soak in 0.7 mol liter-1 NaOCL resulted in 81 and 78% germination, respectively, of 1-year-old seeds, compared to 53% for untreated seeds. These results indicate that showy menodora seeds should be scarified by mechanical means or with 0.7 mol liter-1 NaOCL and planted when average daily minimum/maximum soil temperatures are about 20/30 degrees C for maximum germination.
    • Effects of Temperature on Germination in Three Subspecies of Big Sagebrush

      McDonough, W. T.; Harniss, R. O. (Society for Range Management, 1974-05-01)
      The relationship of germination to temperature was tested in seeds (achenes) from 10 individual plants from each of three subspecies of big sagebrush (Artemisia tridentata Nutt.) collected above 5,000 ft on sagebrush-grass range in Idaho. No optimum temperature for germination within subspecies was found. Subspecies vaseyana gave the lowest mean percent germination (10%) at temperatures in the range 2 degrees-30 degrees C, compared to 28% for subspecies wyomingensis and 38% for subspecies tridentata. Stratification improved germination of seeds in all collections of vaseyana and in some collections of the other two subspecies.
    • Effects of Temperature, Light, and Scarification on Germination of Brownseed Paspalum Seeds

      Flenniken, K. S.; Fulbright, T. E. (Society for Range Management, 1987-03-01)
      Brownseed paspalum (Paspalum plicatulum Michx.) is an important forage grass in tropical and subtropical regions. This study investigated effects of temperature, light, and scarification on germination of seeds from Texas, Australia, South America, and Africa. Seed sources included PI-353399 (Ivory Coast), 'Bryan' (Australia), Paspalum plicatulum 600 (Columbia), and collections from De Witt and Hidalgo Counties, Texas. Untreated seeds and seeds scarified in 17 M sulfuric acid for 20 minutes were germinated under light (12 hours daily) and dark conditions at alternating temperatures of 5-15 (12 hours-12 hours), 10-20, 15-25, 20-30, 25-35, and 30-40 degrees C for 28 days. Seeds from all sources showed similar responses to temperature for percent germination and corrected germination rate index (CGRI). Highest percent germination of Hildalgo seeds occurred at 20-30 and 25-35 degrees C, while that of other sources occurred at 25-35 and 30-40 degrees C. Maximum CGRI for most sources was at 30-40 degrees C. Percent germination was generally higher in light than dark. Scarification increased percent germination and CGRI of De Witt, Hidalgo, PI-353399, and Bryan seeds. Our data indicate that brownseed paspalum seeds are adapted for warm-season germination.
    • Effects of temperature, water potential, and sodium chloride on Indiangrass germination

      Fulbright, T. E. (Society for Range Management, 1988-05-01)
      Indiangrass [Sorghastrum nutans (L.) Nash] is widely used in range seeding. Objectives of this study were to determine the effects of temperature, water potential, and sodium chloride on germination of 'Lometa', 'Cheyenne', 'Llano', 'Oto', and 'Tejas' Indiangrass. Seeds were germinated at 6 alternating temperatures ranging from 5-15 to 30-40 degrees C (12 hours-12 hours). Lometa, Cheyenne, and Tejas seeds were germinated in polyethylene glycol (mol. wt. = 8,000) solutions mixed to approximate water potentials of 0, -0.4, -0.8, -1.2, and -1.6 MPa and in 0, 0.06, 0.12, 0.18, and 0.24 mol liter-1 sodium chloride solutions. Optimum temperatures for percent germination were 10-20 to 25-35, 10-20 to 20-30, and 15-25 and 20-30 degrees C for Cheyenne and Tejas, Llano and Oto, and Lometa seeds, respectively. Percent germination of Cheyenne and Lometa seeds was reduced at water potentials of -0.8 MPa and lower, while Tejas seeds exhibited lower percent germination than controls at -1.2 and -1.8 MPa. Percent germination of Cheyenne and Lometa seeds was reduced by sodium chloride concentrations of 0.12 mol liter-1 and greater. Germination of Tejas seeds was reduced at 0.18 and 0.24 mol liter-1. Indiangrass varieties appear to germinate within a similar range of temperatures but vary in germination response to low water potentials.
    • Effects of Temporary Dehydration on Growth of Green Needlegrass (Stipa viridula Trin.) Seedlings

      Fulbright, T. E.; Wilson, A. M.; Redente, E. F. (Society for Range Management, 1984-09-01)
      Green needlegrass (Stipa viridula Trin.) has been variously rated as "extremely" to "fairly" drought tolerant. This study was conducted to determine the capacity of green needlegrass seedlings for emergence and root growth following temporary dehydration. Germinating seeds were exposed to dehydration treatments of 0, -4, -10, -22, and -37 megapascals (MPa) and then planted in soil-filled pots for a 10-day growth performance test. Exposure of germinating seeds to temporary dehydration treatments of -10 MPa and lower reduced subsequent seedling emergence. When the seminal primary root of germinating seeds was excised or injured by dehydration, seedlings developed up to 3 seminal lateral roots. No additional seminal roots were developed if the seminal primary root was undamaged. Germinating seeds of green needlegrass have relatively low tolerance to dehydration possibly as a result of a low latent potential for development of seminal lateral roots and low tolerance of the embryo and developing tissues to dehydration. Sites to be seeded and planting dates should be selected so as to insure adequate soil moisture for seedling development.
    • Effects of the Plains Pocket Gopher (Geomys bursarius) on Rangeland

      Foster, M. A.; Stubbendieck, J. (Society for Range Management, 1980-01-01)
      Gophers reduced forage production by 18 to 49% on sands and silty range sites in western Nebraska. Determination of percentages of the soil surface that were bare, covered by litter, and occupied by plant bases showed that gopher-disturbed areas contained greater percentages of bare soil and litter than did undisturbed areas. Basal cover of vegetation was highest on undisturbed areas. Frequency of vegetation on gopher mounds of different age was determined. Most perennial grasses increased in frequency on mounds with increasing mound age, while annual grasses and forbs decreased.
    • Effects of the Subterranean Aphid [Geoica utricularia (Passerini)] on Forage Yield and Quality of Sand Lovegrass

      Vogel, K. P.; Kindler, S. D. (Society for Range Management, 1980-07-01)
      In 1977 at Mead, Nebraska, replicated plots in two sand lovegrass (Eragrostis trichodes) nurseries naturally infested with root aphids (Geoica utricularia Passerini) were treated with soil drenches of carbofuran and disulfoton (2.24 kg/ha AI) to quantify the economic importance of these aphids. In a nursery of 'Nebraska 27' sand lovegrass, the carbofuran and disulfoton treated plots produced 45% and 16% more forage, respectively, than the untreated plots. In a nursery of another Nebraska experimental strain, the treated plots produced more forage than the untreated plots but the differences were not significant. There were no differences among treated and control plots in either nursery for dry matter, protein, and in vitro dry matter digestibility percentages.
    • Effects of Tillage and Manure on Emergence and Establishment of Russian Wildrye in a Saltgrass Meadow

      Meuller, D. M.; Bowman, R. A.; McGinnies, W. J. (Society for Range Management, 1985-11-01)
      Saltgrass [Distichlis stricta (Torr.) Rydb.] meadows are found in lowland areas throughout the western United States. Saltgrass meadows are frequently more moist than upland sites and have good production potential if relatively unpalatable saltgrass is replaced by a more palatable species. The electrical conductivity and sodium absorption ratio of saltgrass meadow soils often increase with soil profile depth, while total N and sodium-bicarbonate extractable P decrease. Cultural practices that do not mix the deeper, more saline horizons with the surface should increase seedling germination and establishment. Field studies evaluated the effects of chisel plowing followed by vertical-axis tilling, conventional tilling (moldboard-plowing and discing), and manure (0, 11, 22, 45, and 90 Mg/ha) on soil physical and chemical characteristics as they relate to germination and establishment of Russian wildrye [Elymus junceus Fisch.]. Chisel plowing followed by vertical-axis tilling increased seedling emergence by 23% over conventional tillage. Manure increased seedling growth and emergence, but had no effect on stand ratings. The poor physical conditions created on the conventionally tilled plots when the B and C horizons were brought to the surface and organic matter was buried by the plow are believed to have caused the difference in seedling counts between the two tillage treatments.
    • Effects of top-soil drying on saltcedar photosynthesis and stomatal conductance

      Mounsif, M.; Wan, C.; Sosebee, R. E. (Society for Range Management, 2002-01-01)
      Phreatophytes are trees and shrubs with deep roots tapping the water tables. As such they are presumed to be able to tolerate a water deficit in the top soil. Growth of some phreatophytes is decoupled from environmental factors such as incident precipitation. This study examined the effects of surface soil drying on gas exchange and stomatal conductance of a riparian phreatophyte Tamarix gallica L. (saltcedar) during 2 consecutive growing seasons in which summer precipitation varied substantially. Daily average gas exchange (A) was 13.5 micromol m(-2) sec(-1) in June and 13.4 micromol m(-2) sec(-1) in September, 1991 when surface soil was wet as compared to the same periods of 1990 in which very little rain occurred (6.44 and 8.08 micromol m(-2) sec(-1), respectively, P < 0.0001). Stomatal conductance (g) or maximal conductance showed a similar trend of photosynthesis. Both average gas exchange and stomatal conductance were correlated with water content in the upper portion of the soil (r = 0.83 to 0.88 for A, P < 0.05 and r = 0.65 to 0.70 for g, P < 0.05) in 1990 (a dry year). The variations in gas exchange or stomatac conductance of saltcedar were mainly caused by water availability in the upper soil layers, not by depth to the water table (0.65 vs 2.74 m). The responses of gas exchange and stomatal conductance to surface soil drying in the phreatophyte saltcedar were similar to that of several crop species [lupin (Lupinus cosentinii Guss. cv. Eregulla), wheat (Triticum aestivum L. cv. Cadensa) and sunflower (Helianthus annuus L.)]. Our data suggest that upon soil re-wetting, when water availability to shallow lateral roots increased, the entire root system of saltcedar was actively involved in water uptake, leading to higher stomatal conductance and photosynthesis.
    • Effects of tree canopies on soil characteristics of annual rangeland

      Frost, W. E.; Edinger, S. B. (Society for Range Management, 1991-05-01)
      In the central California region of annual rangeland, herbage production beneath blue oak (Quercus douglasii Hook & Arn.) canopies is greater and production beneath the canopies of interior live oak (Quercus wislizenii DC) and digger pine (Pinus sabiniana Dougl.) is less than that in adjacent open grassland. The objective of this investigation was to assess the impact of these major overstory species on soil-associated characteristics in an effort to explain this tree-herbage production relationship. Greater amounts of organic carbon (OC), greater cation exchange capacity (CEC), lower bulk density, and greater concentrations of some nutrients were found beneath blue oak canopies than in open grassland. This explains, at least in part, the increased herbage production beneath blue oak canopy.
    • Effects of Two Wetting Agents on Germination and Shoot Growth of Some Southwestern Range Plants

      Miyamoto, S.; Bird, J. B. (Society for Range Management, 1978-01-01)
      Two soil wetting agents (linear sulfonate and alkyl polyethylene glycol ether) were evaluated on inhibition of germination and shoot growth of alkali sacaton, galleta, blue grama, and fourwing saltbush. Sacaton and galleta seeds were germinated in wetting agent solutions (185, 370, and 740 ppm by volume) as well as in sand and a water-repellent coal mine spoil sample treated with the wetting agents at rates equivalent to 23.5, 47, 94 liters/ha. Blue grama and saltbush were germinated only in the sand and spoil samples. Results indicate that in solution culture these wetting agents reduce germination, severely deter shoot growth of both sacaton and galleta, and cause nearly permanent injury to plumules of galleta seeds. Wetting agents applied to sand at the comparable rates cause only minor reduction in shoot emergence and growth of the tested grass species, presumably due to soil sorption of wetting agents. The wetting agents tested are potentially phytotoxic, especially the sulfonate compound to saltbush, but can improve shoot emergence when applied to water-repellent media.
    • Effects of Two Years of Irrigation on Revegetation of Coal Surface-Mined Land in Southeastern Montana

      Depuit, E. J.; Skilbred, C. L.; Coenenberg, J. G. (Society for Range Management, 1982-01-01)
      Responses of reseeded vegetation in the first two growing seasons (1978 and 1979) to irrigation on topsoiled sodic mine spoils are presented. In terms of above-ground productivity and stand composition, irrigation significantly promoted growth of seeded perennial grasses and legumes in total. This stimulation was most pronounced in 1979 for the cool-season grasses, slender wheatgrass, smooth bromegrass and western wheatgrass and the invading cool-season legume yellow sweetclover. Other cool-season grasses and warm-season grasses were stimulated by initial irrigation, but were either unaffected or retarded (due to competitive relationships) by continued irrigation. Productivity of invading annual weeds was significantly curtailed by irrigation by 1979. Although differences in composition occurred, total stand productivity was similar for irrigated and nonirrigated plots in 1978, a year of above-average precipitation. In 1979, a drier year, total stand productivity was nearly three times higher under irrigation than nonirrigation. In the first year of study (1978), a higher measured index of stand structural diversity occurred under irrigation. This relationship became reversed in 1979, with higher structural diversity in nonirrigated plots. Root biomass was significantly higher in nonirrigated than in irrigated plots. This difference between irrigation and nonirrigation was most pronounced in the applied topsoil zone. Root distribution was skewed towards shallowest soil depths under irrigation to a far greater extent than under nonirrigation.
    • Effects of Utah Juniper Removal on Herbage Yields from Springerville Soils

      Clary, W. P. (Society for Range Management, 1971-09-01)
      Yields of understory vegetation increased from 223 lb./acre, including 50 lb. of perennial grasses, to 981 lb., including 193 lb. of perennial grasses, after juniper overstory was removed in northern Arizona. Successional trends did not follow a smooth sequence; many areas remained in an annual forb-half-shrub stage for several years.
    • Effects of water quality on cattle performance

      Willms, W. D.; Kenzie, O. R.; McAllister, T. A.; Colwell, D.; Veira, D.; Wilmshurst, J. F.; Entz, T.; Olson, M. E. (Society for Range Management, 2002-09-01)
      Water is an important nutrient for livestock production and is often provided on rangelands directly from ponds or dugouts. Cattle may defecate and urinate into the water thereby adding nutrients and reducing palatability. A study was conducted to examine the effects of water source on cattle production and behavior, to determine the relationship of selected chemical and biological constituents on the observed response and to test the effect of fecal contamination on water consumption. Four dugouts or ponds were selected at 4 sites: 2 in the Fescue Prairie near Stavely in southwestern Alberta, 1 in the Mixed Prairie at Onefour in southeastern Alberta, and 1 in the Palouse Prairie near Kamloops, British Columbia. Yearling Herefords were tested at 3 sites and Hereford cow-calf pairs at 1 Stavely site. At each site, three paddocks radiated from the pond that were stocked with 10 yearlings or cow-calf pairs randomly assigned to either clean water (water delivered to a trough from a well, river, or pond), pond water pumped to a trough (pond(trough)), or direct access into the pond (pond(direct)). The trials were repeated at each site for 3 to 6 years. Observations were made on cattle weight gains, cow backfat thickness, and activity budgets. Fecal samples were analyzed for selected parasites and pathogens. Other experiments were conducted to determine the effects of manure-contaminated water on feed and water consumption and water selection. Calves, with cows drinking clean water, gained 9% more (P < 0.10) weight than those with cows on pond(direct) but cow weight and backfat thickness were not affected. Yearling heifers having access to clean water gained 23% (P = 0.045) and 20% (P = 0.076) more weight than those on pond(direct) and pond(trough), respectively. Cattle avoided water that was contaminated with 0.005% fresh manure by weight when given a choice of clean water. Cattle that had access to clean water spent more time grazing and less time resting than those that were offered pond(trough) or pond(direct). Cattle management must consider water quality together with forage conditions in order to achieve optimal production from rangeland.
    • Effects of Water Spreading on Range Vegetation in Eastern Montana

      Houston, W. R. (Society for Range Management, 1960-11-01)
    • Effects of Water Stress and Temperature on Germination of True Mountainmahogany

      Piatt, J. R. (Society for Range Management, 1976-03-01)
      The effects of five levels of available water and four constant temperature regimes upon the germination of two ecotypic collections of true mountainmahogany (Cercocarpus montanus Raf.) were investigated. Results indicate that moisture stress significantly decreases both the rate and final amount of germination in this species. The amount of moisture stress required to cause these decreases was found to be dependent upon both the seed source and the temperature. Temperature was found to be more important in determining the rate than the amount of germination.
    • Effects of Weaning Date and Prepartum Protein Supplementation on Cow Performance and Calf Growth

      Stalker, L. Aaron; Ciminski, Lane A.; Adams, Don C.; Klopfenstein, Terry J.; Clark, Richard T. (Society for Range Management, 2007-11-01)
      Two experiments evaluated effects of weaning date on cow body condition score (BCS) and calf growth. In Experiment 1, 134 March-calving cows were used in a four-year experiment. Calves were weaned 18 August or 7 November and cows were fed 0 or 0.45 kg protein supplement (42% crude protein) three days per week from 1 December to 28 February while grazing upland range in a 2 by 2 factorial arrangement of treatments. In Experiment 2, spring calving cows (year 1, n = 97; year 2, n = 104) were assigned randomly to one of eight weaning dates at 2-week intervals from 19 August to 25 November. In Experiment 1, weaning in August increased cow BCS precalving (P < 0.001) and prebreeding (P < 0.001), but not pregnancy rates (P = 0.56). Cows fed supplemental protein had greater BCS precalving (P<0.001) and prebreeding (P=0.001) than nonsupplemented cows, but pregnancy rates were similar (P=0.27). Calves born to cows fed supplemental protein prepartum had greater weaning weight than calves born to nonsupplemented cows regardless of whether weaning occurred in August (P = 0.001) or November (P < 0.001). Effects of weaning date on feedlot performance interacted with supplementation treatment. Calves born to cows fed supplement that were weaned in November generated the greatest net returns. In Experiment 2, BCS decreased linearly (P<0.001) as date of weaning was delayed from August to November. Nursing calf gain increased cubically (P < 0.0004) and weaned calf gain from August to November increased quadratically (P < 0.002). Protein supplementation did not affect cow pregnancy rate, but calves born to cows fed protein supplement had greater pre- and postweaning gains. Cow BCS decreased as weaning date was moved later in the year but cow pregnancy rate was not affected by weaning date. 
    • Effects of Wetting and Drying on Germination of Crested Wheatgrass Seed

      Maynard, M. L.; Gates, D. H. (Society for Range Management, 1963-05-01)
    • Effects of Wildfire on Timber and Forage Production in Arizona

      Pearson, H. A.; Davis, J. R.; Schubert, G. H. (Society for Range Management, 1972-07-01)
      A severe May wildfire decimated an unthinned ponderosa pine stand in northern Arizona, while an adjacent thinned stand was relatively undamaged. Radial growth increased on burned trees where crown kill was less than 60% and decreased where crown kill was more than 60%. Burning initially stimulated growth of herbaceous vegetation in both stands. Herbage nutrient value was temporarily enhanced due to burning. Artificially seeded areas produced most herbage 2 years after burning.
    • Effects of Wildlife on Cattle Diets in Laikipia Rangeland, Kenya

      Odadi, Wilfred O.; Young, Truman P.; Okeyo-Owuor, J. B. (Society for Range Management, 2007-03-01)
      The impacts of wild herbivores on cattle diet selection were investigated in an East African rangeland during August 2001 and February 2002. The study compared cattle diets in plots exclusively accessible to cattle (C) and those accessible to megaherbivores (elephants and giraffes), non-megaherbivore wild herbivores > 15 kg (zebras, hartebeests, Grant’s gazelles, oryx, elands, and buffaloes) and cattle (MWC); or non-megaherbivore wild herbivores and cattle (WC). There were no treatment differences in selection of most grass species in either sampling period (P > 0.05). However, selection of forbs differed among treatments during February when conditions were relatively dry and percent of bites taken by cattle on this forage class increased (P < 0.005) from 1.8% +/- 0.3 to 7.7% +/- 1.6 (mean +/- SE). During this period, cattle took a lower percent of bites on forbs in MWC (4.3% +/- 1.7; P = 0.01) and WC (5.9% +/- 2.2; P = 0.03) than in C (12.9% +/- 0.9). These patterns were generally driven by Commelina spp., which comprised 65% +/- 9.4 of total bites on forbs. Notably, these differences were associated with differences in cover of forbs, which was positively correlated with percent of bites on forbs (r2 = 0.86, P < 0.01). Because forbs may be critical components of cattle diets in such rangelands during relatively dry periods, these dietary changes may indicate potential seasonal costs of wildlife to cattle production. Looking for ways to offset such costs may be worthwhile for livestock properties that accommodate wildlife.