• Xeric big sagebrush, a new subspecies in the Artemisia tridentata complex

      Rosentreter, R.; Kelsey, R. G. (Society for Range Management, 1991-07-01)
      In 1970 a xeric form of mountain big sagebrush (Artemisia tridentata ssp. vaseyana (Rydb.) Beetle) was reported in west central Idaho. Observations of morphology, habitat, and ecology, and analyses of foliage chemical components, clearly indicate these plants represent a new subspecies (xericensis) in the big sagebrush complex. It grows at lower elevations, 762-1,524 m (2,500-5,000 ft) and drier environments, 305-560 mm (12-22 in) precipitation, than most mountain big sagebrush, and is found on basaitic foothill soils often in association with bluebunch wheatgrass (Agropyron spicatum (Pursh) Scribn. & Smith). In addition to soil type, the radiate growth form and a more branched paniculate inflorescence are 2 morphological characteristics useful in separating ssp. xericensis from ssp. vaseyana. It contains higher concentrations of crude protein (10.4%), phosphorus (0.3%), and total volatiles, and lower concentrations of tannins and total phenols than mountain big sagebrush. Distinct chromatograms were obtained for both subspecies when extracts were analyzed by gas and high performance liquid chromatography. Leaf morphology and fluorescence of leaf water extracts are useful characters for separating ssp. xericensis from ssp. tridentata. The chemical data, in combination with morphology and ecology, suggest this new subspecies was initially derived by hybridization of ssp. tridentata and ssp. vaseyana.
    • Yaere—Seasonally Inundated Rangeland, West Africa

      Stark, Malcolm (Society for Range Management, 1986-04-01)
    • Yaks

      Miller, Daniel J. (Society for Range Management, 1986-06-01)
    • Yaupon and Associated Vegetation Response to Seasonal Tebuthiuron Applications

      Duncan, K. W.; Scifres, C. J. (Society for Range Management, 1983-09-01)
      Broadcast applications of tebuthiuron pellets (20% active ingredient [a.i.]) at 2 kg/ha (a.i.) in spring more effectively controlled yaupon than applications in summer, fall or winter on the Post Oak Savannah. Tebuthiuron applications in spring reduced the live canopy of yaupon by 80%. Tebuthiuron at 1 kg/ha did not effectively control yaupon, regardless of season of treatment. Herbaceous response to tebuthiuron was relatively slow because of lack of a seed source in the heavy yaupon covers. However, by December 1980 after applications of tebuthiuron at 2 or 4 kg/ha in spring or summer 1978, grass standing crops were significantly increased. Forb standing crops were highly variable, but there was no apparent forb reduction in 1980 of 1981 where herbicide was applied in 1978-1979.
    • Yearlong Grazing of Slash Pine Ranges: Effects on Herbage and Browse

      Pearson, H. A.; Whitaker, L. B. (Society for Range Management, 1974-05-01)
      Total herbage yields under immature slash pine were not appreciably changed by yearlong cattle grazing which removed 30 to 60% of the annual growth. However, moderate (45%) and heavy (60%) grazing reduced pinehill bluestem frequency and increased carpetgrass. Individual browse species were not affected by grazing intensity, but total cover was reduced with moderate grazing. As tree density increased, the total herbage yields decreased.
    • Yearly Variation in Germination in Three Subspecies of Big Sagebrush

      Harniss, R. O.; McDonough, W. T. (Society for Range Management, 1976-03-01)
      Yearly variation in germination between individual plants of three subspecies of big sagebrush (Artemisia tridentata) was examined. The subspecies vaseyana germinated less than tridentata or wyomingensis. Only tridentata showed a significant difference in year-to-year variation. In all years, germination rates of the three subspecies were high enough to exclude seed germination as a limiting factor in sagebrush reinvasion.
    • Yellow-Blossomed Alfalfa on Rangeland in South Dakota

      Smith, Norman G. (Society for Range Management, 1997-08-01)
    • Yes, There Is Grass after Overgrazing

      Hughes, Lee E. (Society for Range Management, 1985-02-01)
    • Yield and Chemical Composition of Coastal Bermudagrass, Rhodesgrass and Volunteer Species Grown on Saline and Nonsaline Soils

      Gonzalez, C. L.; Heilman, M. D. (Society for Range Management, 1977-05-01)
      Yields and chemical composition of coastal Bermudagrass (Cynodon dactylon (L.) Pers.) and Rhodesgrass (Chloris gayana Kunth) grown on saline and nonsaline soils were investigated in the nonirrigated region of the Rio Grande Valley of south Texas. Forage production (3-years average) was 12.9 and 13.8 metric tons per hectare (MT/ha) for coastal Bermudagrass and 16.3 and 13.5 MT/ha for Rhodesgrass in nonsaline and saline soils, respectively, as compared with 7.7 and 7.2 MT/ha for voluntary grasses and forbs. The higher yields of coastal Bermudagrass in saline vs nonsaline soils indicates its greater salt tolerance. Soil salinity did not affect the chemical composition or crude protein content of either grass. Chemical composition of grasses varied yearly, but changes between saline and nonsaline soil treatments followed the same general trend. Growing grasses on saline soils established a mulch on the soil surface and reduced evaporation, but this was not a successful soil reclamation practice, because moisture extraction by roots from saline soil profile caused salt accumulation in the root zone.
    • Yield and Digestibility of Old World Bluestem Grasses as Affected by Cultivar, Plant Part, and Maturity

      Dabo, S. M.; Taliaferro, C. M.; Coleman, S. W.; Horn, F. P.; Claypool, P. L. (Society for Range Management, 1987-01-01)
      Old World bluestems (Bothriochloa spp.) have been used in the U.S. for over 60 years but few data are available on effects of management or cultivar differences for forage yield and quality. Field experiments were conducted on a Kirkland silt loam (Uderic Paleustoll) soil for 2 years (1982-83), in order to assess the yield and quality of 4 such cultivars as affected by maturation and plant part. The experimental design was a split-split plot, in a randomized complete block, with 4 replications, 4 cultivars ('Caucasian', 'Ganada', 'Plains', 'WW Spar'), 10 harvest dates, and 3 plant parts (whole plant, stem, and leaf). Cultivars were main plots; harvest dates and plant parts were sub and sub-sub plots, respectively. Response variables were dry matter yield (DMY), in vitro dry matter disappearance (IVDMD), leaf to stem ratio (L/S), and in vitro digestible dry matter yield (IVDDMY). Ganada consistently had the lowest leaf, stem, and whole plant DMY and IVDDMY. Caucasian had higher leaf, stem, and whole plant DMY and IVDDMY than Plains and WW-Spar in 1983, but the DMY and IVDDMY of these cultivars were similar in 1982. Quadratic and linear equations were satisfactorily fit to the DMY and IVDDMY data in 1982 and 1983, respectively. The IVDMD in whole plant samples decreased at average rates of 4.2 and $5.5 g kg ha-1 daily in 1982 and 1983, respectively, during harvest week one. Among cultivars, Caucasian had the highest rate of decline and Ganada the lowest. The decline was quadratic in nature and faster in stem fractions. Cultivar IVDMD differences were consistent over plant parts. Ganada and Caucasian had the highest and lowest IVDMD concentrations, respectively. Plains and WW-Spar had IVDMD values of similar magnitude and intermediate to those of Ganada and Caucasian. Cultivar leaf to stem ratios were similar in 1982 but different in 1983 with Plains and Caucasian having higher L/S ratios than Ganada and WW-Spar. For these cultivars leafiness was a poor indicator of digestibility.
    • Yield and feeding of prairie grasses in east-central Alberta

      Suleiman, A.; Okine, E. K.; Goonewardene, L. A.; Day, P. A.; Yaremcio, B.; Recinos-Diaz, G. (Society for Range Management, 1999-01-01)
      Information on the yield of grasses as the plants mature is useful to optimize grazing potential and quality hay production. The objectives of this study were to compare the yield and feeding value of 11 common prairie grasses over 2 yearly cycles of growth and determine which of the grasses may require supplementation to meet nutrient requirements of grazing cattle. Dry matter yield (DM), crude protein (CP), acid detergent fiber (ADF), calcium (Ca), and phosphorus (P) values were obtained for brome (Bromus inermis [L.]), creeping red fescue (Festuca rubra [L.]), crested wheatgrass (Agropyron cristatum [L.] Gaertn), intermediate wheatgrass (Agropyron intermedium (host) Beauv), meadow foxtail (Alopecurus pratensis [L.]), orchardgrass (Dactylis glomerata [L.]), pubescent wheatgrass (Agropyron trichophorum Link. richt), streambank wheatgrass (Agropyron riparium Scriba &Smith), slender wheatgrass (Agropyron trachycaulum Link Malte), tall fescue (Festuca arundinacea Schreb), and timothy (Phleum pratense [L.]) at weekly intervals from June to September, in 1992 and 1993. Most grasses reached maximum yields at week 8 in 1992 (drought year) and week 12 in 1993 (normal year). Herbage mass yields (g/0.25m2 at week 8 in 1992 (highest to lowest yielding) were crested wheatgrass (235), intermediate wheatgrass(210), pubescent wheatgrass(173), brome(161), slender wheatgrass(152), meadow foxtail(114), Tall fescue(110), timothy(101), orchardgrass(83), creeping red fescue(56), and streambank wheatgrass(50). Herbage mass yields pattern of the grasses in 1993 was similar to that in 1992 except for crested wheatgrass and brome which ranked first and fourth in 1992 but ranked fifth and second, in 1993, respectively. Quality declined in all grasses as they matured. The average CP content of grasses declined from 24% to 13% in 1992 and from 21.5% to 12.1% in 1993 but were adequate to meet crude protein requirements of growing, pregnant or lactating grazing cattle. The Ca levels in all grasses were adequate for all classes of cattle on pasture but the low P levels of 0.11% in both years indicate that growing, pregnant or lactating cattle grazing on these pastures would require P supplementation.
    • Yield and Mineral Composition of Grass Species Grown on Acid Grassland Soils

      Guerrero, F. P.; Williams, W. A.; Martin, W. E. (Society for Range Management, 1967-03-01)
      The objective was to study the use of various grass species, two liming materials, and phosphorus as means of improving very acid, unproductive, grassland soils. Phosphorus applications increased yields of all 10 species at all levels of liming. Liming with a mixture of calcic and magnesium limes increased yield more than either alone. The outstanding performance of veldtgrass was associated with its calcium-foraging ability, which resulted in the highest tissue concentrations of calcium. These guidelines point toward the use of phosphorus and small amounts of limestone, containing both Ca and Mg, with calcium-foraging species for successful forage establishment in acid grassland soils.
    • Yield and N Uptake by Seven Perennial Grass Species as Affected by High Rates of N Fertilizer

      Lutwick, L. E.; Smith, A. D. (Society for Range Management, 1979-11-01)
      Seven species of grass were grown on plots to which N had been applied at progressively increasing rates (0 to 775 kg N/ha) to reach and exceed those required for maximum yields. Yield of hay and protein in all seven grasses increased with N fertilizer. Recoveries of N were only 12 to 31% when applied once, and 8 to 14% when applied every year. Because these recoveries are considered to be uneconomical, massive rates of N fertilizer are not recommended. Intermediate wheatgrass produced the most hay and protein. All seven grasses responded most to applied N in the first 2 years after application, regardless of age of stand.
    • Yield and Nutritional Quality of Intermediate Wheatgrass Infested by Black Grass Bugs at Low Population Densities

      Malechek, J. C.; Gray, A. M.; Haws, B. A. (Society for Range Management, 1977-03-01)
      Black grass bugs (Labops hesperius) at a population density of 156 bugs per square meter did not affect herbage yields of intermediate wheatgrass but depressed seedhead production 56%. They caused a small but significant increase in concentrations of crude protein and a slight decrease in cellular contents.
    • Yield and Protein Content of Sandyland Range Forages as Affected by Three Nitrogen Fertilizers

      Pettit, R. D.; Deering, D. W. (Society for Range Management, 1974-05-01)
      A west Texas sandyland range site was fertilized with two rates, (30 and 60 kg/ha of actual N) of ammonium nitrate (AN), ammonium sulfate (AS) and ammonium phosphate-sulfate (APS) on June 2, 1972. Yield samples taken in mid-August showed all fertilizer treatments to significantly increase total yields. The 60 kg/ha of N treatments of AS and APS produced more herbage than all other fertilizer treatments. Climax decreasers on the site, little bluestem (Schizachyrium scoparium) and sideoats grama (Bouteloua curtipendula), showed less yield response to fertilization than increaser and invader grasses. Crude protein analysis of leaf tissue showed the grasses of the control (ON) to contain significantly less and the grasses treated with 60 kg/ha of N as AN to contain more protein than other treatments. Sulfur appears to be more important than phosphorus in increasing yields on this site. Also, range condition should be at least high fair before fertilizer is applied to minimize competition between the desirable and invader plants.
    • Yield and Quality of Creeping Bluestem as Affected by Time of Cutting

      Kalmbacher, R. S.; Martin, F. G.; Andrade, J. M. S. (Society for Range Management, 1981-11-01)
      Creeping bluestem (Schizachyrium stoloniferum Nash.) is a rhizomatous native grass that is the dominant species on many Florida rangelands. To evaluate its grazing potential, dry matter yield, in vitro organic matter digestibility (IVOMD), crude protein, neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL), were measured in plants cut at 10 and 20 cm stubble heights during 70-day intervals from June to October (summer), August to December (summer-fall), and October to February (winter). Winter yields were significantly greater (2,090 kg/ha) than summer yields (1,600 kg/ha) with summer-fall yields intermediate (1,860 kg/ha). After 3 years there was a significant decline in dry matter in plants cut at 10 cm, but yield was sustained in plants cut at 20 cm. Herbage regrowth in July to August was high in IVOMD (37.8%). Crude protein and IVOMD percentages were also greater in November to December regrowth (7.5 and 36%, respectively) and January to February regrowth (6.8 and 37%, respectively). However, since forage yield was lowest at the time, yield of protein and digestible organic matter were lowest. Percent NDF, ADF, and ADL were not greatly affected by initial growth or regrowth periods and averaged 80.0, 42.3 and 5.8%, respectively. Creeping bluestem may be one of Florida's greater yielding native grasses, but will require protein and energy supplements to provide good livestock performance.
    • Yield and quality of RS-2, a quackgrass X bluebunch wheatgrass hybrid

      Haferkamp, M. R.; Adams, D. C.; Borman, M. M.; Grings, E. E.; Currie, P. O. (Society for Range Management, 1995-07-01)
      Understanding the effect of defoliation frequency and N fertilization on plant growth, forage yield, and quality of RS-2, a quackgrass [Elytrigia repens (L.) Nevski.] x bluebunch wheat grass [Pseudoroegneria spicata (Pursh.) Love] hybrid, will help promote efficient use of this hybrid in livestock production systems. Plants were fertilized with 0, 112, or 224 kg N ha-1 in spring 1988 and 1989, or with a 112 + 112 kg N ha-1 split in spring and summer. One set of plants was unmowed or mowed to a 5cm stubble height once in July or August in 1988 and another set was mowed initially in May, June, July, August, September, or October 1989 and monthly thereafter through October. Peak standing crop of unmowed plants was 3,470 kg ha-1 in 1988 and 5,850 kg ha-1 in 1989. In 1989 yields of fertilized plants exceeded those of unfertilized plants by 1,000 kg ha-1. In 1988, crude protein exceeded 12% in unmowed forage and in 1989 varied from 20% in May to 8% in August. After fertilization, crude protein was increased by 2 to 4 percentage units in 1988 and by 2 percentage units in 1989, but fertilization had no effect on in vitro digestible organic matter. Regrowth contained more crude protein (15-22%) and digestible organic matter (29-40%) than unmowed forage. Sequential harvesting enhanced quality of regrowth, but standing crops did not exceed 350 kg ha-1; except in June 1989. Sixty percent of the accumulated yield was harvested with the first mowing during May through August. Plots harvested initially in September and October were only harvested once. Our findings indicate an increase in forage yield potential and forage quality of RS-2 after harvesting and fertilizing the RS-2 hybrid.
    • Yield and quality of warm-season grasses in central Texas

      Sanderson, M. A.; Voigt, P.; Jones, R. M. (Society for Range Management, 1999-03-01)
      Warm-season perennial bunchgrasses frequently are used for hay and grazing in central Texas. We compared 6 alternative grasses with 2 more commonly grown species ['Ermelo' weeping lovegrass, (Eragrostis curvula (Schrad.) Nees var. curvula Nees) and 'Selection-75' kleingrass (Panicum coloratum L.] on 2 soils during 2 years. Grasses were transplanted into field plots at Stephenville and Temple, Tex. 1993 and harvested 3 times in 1994 and 1995. Weeping lovegrass and 'WW-B.Dahl' old world bluestem [Bothriochloa bladhii (Retz) S.T. Blake] were the highest yielding (P < 0.05) grasses and averaged 9,350 and 7,630 kg dry matter ha(-1) in 1994 and 1995, respectively. 'Irene' tufted digitgrass (Digitaria eriantha Stued.) and kleingrass produced similar (P > 0.05) yields (6,560 and 6,340 kg dry matter ha(-1)). Experimental line 409-704 buffelgrass [Cenchrus ciliaris L. syn. Pennisetum ciliare (L.) Link], 'Carostan' flaccidgrass (Pennisetum flaccidum Greisb.), 'Palar' Wilman lovegrass (Eragrostis superba Peyr.), and P.I. 269961 Oriental pennisetum (Pennisetum orientale Rich) yielded less than 3,000 kg dry matter ha(-1) at Stephenville and were invaded by weeds. Tillers per plant generally explained most of the yield differences as plant density was held constant. Ermelo lovegrass and WW-B.Dahl old world bluestem produced 2 to 3 times more tillers plant(-1) than other grasses. Concentrations of neutral detergent fiber were higher (P < 0.05) in digitgrass and the lovegrasses than in other grasses (39 vs 36% of dry matter). These data indicate that WW-B.Dahl old world bluestem and Irene tufted digit-grass should be useful in forage-livestock systems in central Texas.
    • Yield and quality of WW-Iron Master and caucasian bluestem regrowth

      White, L. M.; Dewald, C. L. (Society for Range Management, 1996-01-01)
      Old World bluestems (Bothriochloa spp.) have been seeded on over a million hectares of marginal farmland in Oklahoma and Texas, yet we know little about their regrowth yield and quality. The objective was to determine seasonal pattern of forage regrowth yield and quality of leaves and stems of WW-Iron Master (B. ischaemum [L.] Keng) and Caucasian (B. caucasica [Trin.] C.E. Hubb.) bluestem when 4-week regrowth was harvested at weekly intervals from early May through mid-September. Four plots of each bluestem were established in each of the 4 blocks (32 plots total). Harvesting was rotated so that 4-week regrowth of each bluestem was harvested weekly from 1 of the 4 plots in each block during 1988 and 1989 to determine regrowth yield, in vitro dry matter digestibility (IVDMD), and crude protein (CP) of leaves and stems. Forage regrowth of both species peaked in June both years. Regrowth during August averaged 10 and 35% of June regrowth in 1988 and 1989. WW-Iron Master produced 80 and 45 % greater 4-week regrowth than Caucasian in 1988 and 1989. WW-Iron Master produced 75 and 28% greater leaf regrowth than Caucasian in 1988 and 1989 and twice as many stems both years. Leaf and stem IVDMD of WW-Iron Master averaged 2 to 6 percentage units higher than Caucasian. Leaf CP of WW-Iron Master averaged 2 percentage units higher than Caucasian during May and June. However, stem CP of WW-Iron Master averaged 1 percentage unit lower than Caucasian. Grazing management plans need to consider that the majority of bluestem forage production was restricted to a 1 month period in June. This technique of sampling 4-week regrowth every week during the growing season was an effective method for determining the seasonal regrowth pattern.
    • Yield of Three Range Grasses Grown Alone and in Mixtures with Legumes

      McGinnies, W. J.; Townsend, C. E. (Society for Range Management, 1983-05-01)
      Four legumes and 3 grasses in combination, and the 3 grasses alone were evaluated for forage yield and persistence for 9 years in north-central Colorado. Sicklepod milkvetch (Astragalus falcatus), alfalfa (Medicago sativa), sainfoin (Onobrychis viciifolia) or crownvetch (Coronilla varia) were planted in alternate rows with crested wheatgrass (Agropyron desertorum), Russian wildrye (Elymus junceus), or pubescent wheatgrass (A. trichophorum). Crownvetch failed to become established. Sainfoin, a short-lived species under Colorado range conditions, was gone within 5 years. Alfalfa persisted 7 years; it was killed by a combination of drought and pocket gophers. Sicklepod milkvetch persisted for the entire period. This site was too dry for pubescent wheatgrass and its stand declined rapidly. Crested wheatgrass with sicklepod milkvetch or alfalfa, and Russian wildrye with alfalfa produced the highest total yields. All grass-legume mixtures involving crested wheatgrass and Russian wildrye produced significantly more forage than the grasses grown alone in 30 cm row spacing. Crude protein content was higher for grass-legume mixtures than for the grass alone.