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Christopher A Davis - One of the best experts on this subject based on the ideXlab platform.
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environmental controls on the simulated diurnal cycle of Warm Season precipitation in the continental united states
Journal of the Atmospheric Sciences, 2010Co-Authors: Stanley B Trier, Christopher A Davis, David AhijevychAbstract:Abstract The diurnal cycle of Warm-Season precipitation in the Rocky Mountains and adjacent Great Plains of the United States is examined using a numerical modeling framework designed to isolate the role of terrain-influenced diurnally varying flows within a quasi-stationary longwave pattern common to active periods of midsummer convection. Simulations are initialized using monthly averaged conditions and contain lateral boundary conditions that vary only with the diurnal cycle. Together these attributes mitigate effects of transient weather disturbances originating upstream of the model domain. After a spinup period, the final 7 days of the 10-day model integration are analyzed and compared with observations. Results indicate that many salient features of the monthly precipitation climatology are reproduced by the model. These include a stationary afternoon precipitation frequency maximum over the Rocky Mountains followed overnight by an eastward-progressing zone of maximum precipitation frequencies conf...
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corridors of Warm Season precipitation in the central united states
Monthly Weather Review, 2006Co-Authors: John D Tuttle, Christopher A DavisAbstract:Abstract During the Warm Season in the central United States there often exists a corridor of precipitation where a succession of mesoscale convective systems (MCSs) follow similar paths lasting several days. The total cumulative rainfall within a corridor can be substantial while precipitation at nearby regions may be below normal. Understanding the nature of the corridors and the environmental factors important for their formation thus has important implications for quantitative precipitation forecasting and hydrological studies. In this study a U.S. national composite radar dataset and model-analyzed fields are used for the 1998–2002 Warm Seasons (July–August) to understand the properties of corridors and what environmental factors are important for determining when and where they develop. The analysis is restricted to a relatively narrow longitudinal band in the central United States (95°–100°W), a region where convection often intensifies and becomes highly organized. It is found that ∼68% of MCSs we...
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Coherence of Warm-Season continental rainfall in numerical weather prediction models
Monthly Weather Review, 2003Co-Authors: Christopher A Davis, Richard E Carbone, Stanley B Trier, Kevin W. Manning, John D TuttleAbstract:Abstract A recent study by Carbone et al. revealed “episodes” of Warm-Season rainfall over North America characterized as coherently propagating signals often linking multiple mesoscale convective systems over spatial scales of 1000–3000 km and timescales of 1–3 days. The present study examines whether these propagating signals are found in two numerical weather prediction (NWP) models commonly used today, namely, the Eta Model from the National Centers for Environmental Prediction and the newly developed Weather Research and Forecast (WRF) model. The authors find that the diurnal cycle of rainfall over much of the United States east of the Rockies is poorly represented, particularly over the central United States, where a nocturnal rainfall maximum is observed. Associated with this nocturnal maximum is an axis of propagating rainfall emanating from the western High Plains in the late afternoon, extending across the Midwest overnight, and occasionally continuing to the Appalachians on the second day. This...
J L Foster - One of the best experts on this subject based on the ideXlab platform.
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the future of Warm Season tropical and subtropical forage legumes in sustainable pastures and rangelands
African Journal of Range & Forage Science, 2014Co-Authors: James P Muir, José C. B. Dubeux, W. D. Pitman, J L FosterAbstract:Forage legumes have the potential to contribute substantially to Warm-Season, subtropical and tropical pastures and rangelands. Compared to grasses, they have advantages in accessing subsoil nutrients and moisture; legumes typically concentrate protein in forage, even in infertile soils, and they can also provide ruminants with plant proteins and soluble carbohydrates that increase digestibility of grasses when consumed in legume–grass mixtures. Yet their inclusion in Warm-Season, subtropical or tropical pasture seed mixes or rangeland rehabilitation is minimal considering the percentage of grasslands coverage in these regions. Why have past diligent attempts failed to develop the germplasm, agronomic techniques, dissemination and ultimate widespread acceptance by land managers in regions where these legumes are widely adapted? Successful forage legume reports indicate that farmers’ participation in technology development, persistence with minimal management, adequate seed supply following release of new ...
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sustainable low input Warm Season grass legume grassland mixtures mission nearly impossible
Grass and Forage Science, 2011Co-Authors: James P Muir, W. D. Pitman, J L FosterAbstract:Grazing lands in Warm-temperate and subtropical North America have become less diverse. Pastures are typically grass monocultures, while rangelands are generally managed for the grass components. Overstocking, selective herbicides, fire exclusion and heavy rates of nitrogen fertilizer have contributed to near exclusion of native, Warm-Season legumes. The simplicity of managing grass monocultures, pasture production responses to nitrogen fertilizer and profitability of grass-only systems have limited interest in legume-based approaches. Changing economics and ecological concerns with ecosystem accumulation of industrial inputs contribute to an increasing interest in legumes. Unlike the development of temperate pasture legumes and recent research in the tropics, legumes tolerant of both freezing temperatures and hot weather have received less attention. Poor establishment, limited persistence and potential invasiveness limit currently available introduced species. Native, herbaceous, Warm-Season legume species occur throughout Warm-temperate North America, but little attention has been directed to these plants as potential forage species. Some success with a few native legume species, primarily in the genus Desmanthus, suggests potential for expanded assessment of forage value of the many species available. Current assessments of native legumes, primarily for conservation purposes, provide an opportunity to expand evaluations of these species for pasture and rangeland potential while economics of livestock production and public interest in ecosystem health are supportive. Experiences with legumes of Warm-temperate origin in North America, along with results with temperate and tropical pasture legumes globally, provide a starting point for future efforts at incorporating greater legume diversity in pastures and rangelands of subtropical and Warm-temperate regions around the world.
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intake digestibility and nitrogen retention by sheep supplemented with Warm Season legume haylages or soybean meal
Journal of Animal Science, 2009Co-Authors: J L Foster, J N Carter, A T Adesogan, A R Blount, R O Myer, Sharad C PhatakAbstract:The high cost of commercial supple- ments necessitates evaluation of alternatives for rumi- nant livestock fed poor quality Warm-Season grasses. This study determined how supplementing bahiagrass haylage (Paspalum notatum Flugge cv. Tifton 9) with soybean (Glycine max (L.) Merr.) meal or Warm-Season legume haylages affected the performance of lambs. Forty-two Dorper × Katadhin lambs (27.5 ± 5 kg) were fed for ad libitum intake of bahiagrass haylage (67.8% NDF, 9.6% CP) alone (control) or supplemented with soybean meal (18.8% NDF, 51.4% CP) or haylages of annual peanut (Arachis hypogaea (L.) cv. Florida MDR98; 39.6% NDF, 18.7% CP), cowpea (Vigna un- guiculata (L.) Walp. cv. Iron clay; 44.1% NDF, 16.0% CP), perennial peanut (Arachis glabrata Benth. cv. Flo- rigraze; 40.0% NDF, 15.8% CP), or pigeonpea (Cajanus cajan (L.) Millsp. cv. GA-2; 65.0% NDF, 13.7% CP). Haylages were harvested at the optimal maturity for maximizing yield and nutritive value, wilted to 45% DM, baled, wrapped in polyethylene plastic, and en- siled for 180 d. Legumes were fed at 50% of the dietary DM, and soybean meal was fed at 8% of the dietary DM to match the average CP concentration (12.8%) of legume haylage-supplemented diets. Lambs were fed each diet for a 14-d adaptation period and a 7-d data collection period. Each diet was fed to 7 lambs in period 1 and 4 lambs in period 2. Pigeonpea hay- lage supplementation decreased (P < 0.01) DM and OM intake and digestibility vs. controls. Other legume haylages increased (P < 0.05) DM and OM intake vs. controls; however, only soybean meal supplementation increased (P = 0.01) DM digestibility. All supplements decreased (P = 0.05) NDF digestibility. Except for pi- geonpea haylage, all supplements increased (P < 0.01) N intake, digestibility, and retention, and the responses were greatest (P = 0.04) with soybean meal supple- mentation. Microbial N synthesis was reduced (P = 0.02) by pigeonpea haylage supplementation, but unaf- fected (P = 0.05) by other supplements. Efficiency of microbial protein synthesis was unaffected (P = 0.05) by diet. Ruminal ammonia concentration was increased (P = 0.01) by all supplements, but only soybean meal and annual peanut haylage increased (P < 0.03) plasma urea-N concentrations. Perennial peanut, annual pea- nut, and cowpea haylages are promising protein supple- ments for growing lambs.
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intake digestibility and nitrogen retention by sheep supplemented with Warm Season legume haylages or soybean meal
Journal of Animal Science, 2009Co-Authors: J L Foster, J N Carter, A T Adesogan, A R Blount, R O Myer, Sharad C PhatakAbstract:The increasing cost of feed supplements necessitates evaluation of alternatives for ruminant livestock grazing poor quality Warm-Season grasses. This study determined how supplementing bahiagrass hay (Paspalum notatum Flugge cv. Pensacola) with soybean [Glycine max (L.) Merr.] meal or Warm-Season legume hays affected intake, digestibility, and N utilization by lambs. Dorper x Katadhin crossbred lambs (30.6 +/- 5.5 kg; n = 42) were fed bahiagrass hay (73.8% NDF, 8.1% CP) for ad libitum intake and supplemented with nothing (control), soybean meal, or hays of annual peanut [Arachis hypogaea (L.) cv. Florida MDR98; 46.2% NDF, 14.7% CP], cowpea [Vigna unguiculata (L.) Walp. cv. Iron clay; 62.2% NDF, 11.7% CP], perennial peanut (Arachis glabrata Benth. cv. Florigraze; 43.3% NDF, 15.2% CP), pigeonpea [Cajanus cajan (L.) Millsp. cv. GA-2; 78.6% NDF, 12.2% CP], or soybean (cv. Pioneer 97B52; 59.0% NDF, 13.5% CP). Legume hays were supplemented at 50% of total diet DM, and soybean meal was supplemented at a level (4.25% of diet DM) that matched the average dietary CP content (10.8%) of the legume hay-supplemented diets. The cowpea, pigeonpea, and soybean were harvested at respective maturities that maximized DM yield and nutritive value, and the peanuts were first cuttings. Diets were fed to 6 lambs per treatment for 2 consecutive 21-d periods. Supplementation with hays of annual and perennial peanut, cowpea, and soybean increased (P < 0.01) DMI vs. control, but apparent DM digestibility was only increased (P = 0.03) by supplementation with annual or perennial peanut hay. Compared with the control, N intake, digestibility, and retention were increased (P < 0.01) by supplementation with legume hay or soybean meal. Responses were greatest when annual or perennial peanut hays were fed. Ruminal ammonia concentration was increased (P < 0.01) by all legume hay supplements vs. the control. Microbial N synthesis and ruminally degraded OM were increased (P = 0.03) by perennial and annual peanut hay supplementation, but efficiency of microbial synthesis was not different (P = 0.52) among diets. Unlike other supplements, annual and perennial peanut hays increased DM and N intake and digestibility and improved microbial N synthesis; therefore, they were the best supplements for the bahiagrass hay under the conditions of this study.
John D Tuttle - One of the best experts on this subject based on the ideXlab platform.
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rainfall occurrence in the u s Warm Season the diurnal cycle
Journal of Climate, 2008Co-Authors: Richard E Carbone, John D TuttleAbstract:The diurnal occurrence of Warm-Season rainfall over the U.S. mainland is examined, particularly in light of forcings at multiple scales. The analysis is based on a radar dataset of 12-Seasons duration covering the U.S. mainland from the Continental Divide eastward. The dataset resolves 2-km features at 15-min intervals, thus providing a detailed view of both large- and regional-scale diurnal patterns, as well as the statistics of events underlying these patterns. The results confirm recent findings with respect to the role of propagating rainfall systems and the high frequency at which these are excited by sensible heating over elevated terrain. Between the Rockies and the Appalachians, 60% of midsummer rainfall occurs in this manner. Most rainfall in the central United States is nocturnal and may be attributed to the following three main forcings: 1) the passage of eastward-propagating rainfall systems with origins near the Continental Divide at 105°W; 2) a nocturnal reversal of the mountain–plains solenoid, which is associated with widespread ascent over the plains; and 3) the transport of energetic air and moisture convergence by the Great Plains low-level jet. Other features of interest include effects of the Appalachians, semidiurnal signals of regional significance, and the impact of breezes along the Gulf of Mexico. A modest effort was put forth to discern signals associated with El Nino and the Southern Oscillation. While tendencies in precipitation patterns are observed, the record is too short to draw conclusions of general significance.
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corridors of Warm Season precipitation in the central united states
Monthly Weather Review, 2006Co-Authors: John D Tuttle, Christopher A DavisAbstract:Abstract During the Warm Season in the central United States there often exists a corridor of precipitation where a succession of mesoscale convective systems (MCSs) follow similar paths lasting several days. The total cumulative rainfall within a corridor can be substantial while precipitation at nearby regions may be below normal. Understanding the nature of the corridors and the environmental factors important for their formation thus has important implications for quantitative precipitation forecasting and hydrological studies. In this study a U.S. national composite radar dataset and model-analyzed fields are used for the 1998–2002 Warm Seasons (July–August) to understand the properties of corridors and what environmental factors are important for determining when and where they develop. The analysis is restricted to a relatively narrow longitudinal band in the central United States (95°–100°W), a region where convection often intensifies and becomes highly organized. It is found that ∼68% of MCSs we...
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Coherence of Warm-Season continental rainfall in numerical weather prediction models
Monthly Weather Review, 2003Co-Authors: Christopher A Davis, Richard E Carbone, Stanley B Trier, Kevin W. Manning, John D TuttleAbstract:Abstract A recent study by Carbone et al. revealed “episodes” of Warm-Season rainfall over North America characterized as coherently propagating signals often linking multiple mesoscale convective systems over spatial scales of 1000–3000 km and timescales of 1–3 days. The present study examines whether these propagating signals are found in two numerical weather prediction (NWP) models commonly used today, namely, the Eta Model from the National Centers for Environmental Prediction and the newly developed Weather Research and Forecast (WRF) model. The authors find that the diurnal cycle of rainfall over much of the United States east of the Rockies is poorly represented, particularly over the central United States, where a nocturnal rainfall maximum is observed. Associated with this nocturnal maximum is an axis of propagating rainfall emanating from the western High Plains in the late afternoon, extending across the Midwest overnight, and occasionally continuing to the Appalachians on the second day. This...
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inferences of predictability associated with Warm Season precipitation episodes
Journal of the Atmospheric Sciences, 2002Co-Authors: Richard E Carbone, John D Tuttle, David Ahijevych, Stanley B TrierAbstract:Herein preliminary findings are reported from a radar-based climatology of Warm Season precipitation ‘‘episodes.’’ Episodes are defined as time‐space clusters of heavy precipitation that often result from sequences of organized convection such as squall lines, mesoscale convective systems, and mesoscale convective complexes. Episodes exhibit coherent rainfall patterns, characteristic of propagating events, under a broad range of atmospheric conditions. Such rainfall patterns are most frequent under ‘‘weakly forced’’ conditions in midsummer. The longevity of episodes, up to 60 h, suggests an intrinsic predictability of Warm Season rainfall that significantly exceeds the lifetime of individual convective systems. Episodes are initiated primarily in response to diurnal and semidiurnal forcings. Diurnal forcing is dominant near the Rocky and Appalachian Mountains, whereas semidiurnal forcing is dominant between these cordilleras. A most common longitude of origin is at or near the east slope of the Continental Divide (1058W). These observations are consistent with a condition of continual thermal forcing, widespread hydrodynamic instability, and the existence of other processes that routinely excite, maintain, and regenerate organized convection. The propagation speed of major episodes is often in excess of rates that are easily attributable either to the phase speeds of large-scale forcing or to advection from low- to midlevel ‘‘steering’’ winds. It is speculated that wavelike mechanisms, in the free troposphere and/or the planetary boundary layer, may contribute to the rates of motion observed. Once understood, the representation of such mechanisms in forecast models offers the opportunity for improved predictions of Warm Season rainfall.
James P Muir - One of the best experts on this subject based on the ideXlab platform.
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the future of Warm Season tropical and subtropical forage legumes in sustainable pastures and rangelands
African Journal of Range & Forage Science, 2014Co-Authors: James P Muir, José C. B. Dubeux, W. D. Pitman, J L FosterAbstract:Forage legumes have the potential to contribute substantially to Warm-Season, subtropical and tropical pastures and rangelands. Compared to grasses, they have advantages in accessing subsoil nutrients and moisture; legumes typically concentrate protein in forage, even in infertile soils, and they can also provide ruminants with plant proteins and soluble carbohydrates that increase digestibility of grasses when consumed in legume–grass mixtures. Yet their inclusion in Warm-Season, subtropical or tropical pasture seed mixes or rangeland rehabilitation is minimal considering the percentage of grasslands coverage in these regions. Why have past diligent attempts failed to develop the germplasm, agronomic techniques, dissemination and ultimate widespread acceptance by land managers in regions where these legumes are widely adapted? Successful forage legume reports indicate that farmers’ participation in technology development, persistence with minimal management, adequate seed supply following release of new ...
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molecular weight and protein precipitating ability of condensed tannins from Warm Season perennial legumes
Journal of Plant Interactions, 2014Co-Authors: H D Naumann, James P Muir, L O Tedeschi, B D Lambert, Ann E Hagerman, M M KothmannAbstract:The beneficial effects of forages containing condensed tannins (CTs) on ruminants are well documented, but the chemical features of CT that yield benefits have not been defined. Some evaluations of limited numbers of highly purified compounds have resulted in positive correlations between CT molecular weight (MW) and biological activity, while others have failed to show a correlation. The objectives of this study were to determine if MW of CT could predict biological activity relative to protein precipitability. MW of condensed tannin, protein-precipitable phenolics (PPP), and the amount of protein bound (PB) were determined for nine species of Warm-Season perennial legumes. There was no correlation between PPP or PB and MW (R2 0.11 and R2 0.02, respectively). However, CT concentration did correlate with PPP and PB (R2 0.81 and R2 0.69, respectively). It was concluded that CT MW does not explain the variation in protein precipitation by CT from the forage legumes surveyed.
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effect of molecular weight of condensed tannins from Warm Season perennial legumes on ruminal methane production in vitro
Biochemical Systematics and Ecology, 2013Co-Authors: H D Naumann, James P Muir, L O Tedeschi, B D Lambert, M M KothmannAbstract:The objectives of the present study were to determine if the molecular weight of condensed tannins (CT) from Warm-Season perennial legumes affects the biological activity of CT relative to suppression of methane (CH4) production by ruminants, and to identify potential North American native forage plants to use for mitigation of enteric CH4 emission. Eight North American native Warm-Season perennial legumes were evaluated: Leucaena retusa Benth. (littleleaf leadtree), Desmanthus illinoensis (Michx.) MacMill. Ex B.L. Rob. & Fernald (Illinois bundleflower), Lespedeza stuevei Nutt. (tall lespedeza), Mimosa strigillosa Torr. & A. Gray (powderpuff), Neptunia lutea (Leavenworth) Benth. (yellow puff), two ecotypes of Acacia angustissima var. hirta (Nutt.) B.L. Rob (prairie acacia), and Desmodium paniculatum (L.) DC. var. paniculatum (panicledleaf ticktrefoil). Two introduced legumes were also included: Arachis glabrata Benth. (rhizoma peanut) and Lespedeza cuneata (Dum. Cours.) G. Don (sericea lespedeza). Forages were fermented with cattle rumen fluid for 48 h anaerobically using an in vitro gas production technique. D. paniculatum, L. stuevei, and M. strigillosa were high in CT, ranging from 11.7 to 12.5%. D. illinoensis, L. cuneata, N. lutea, and two ecotypes of A. angustissima var. hirta had less CT (P < 0.05), ranging from 8.1 to 8.9%, whereas L. retusa and A. glabrata had the least CT (P < 0.05), measuring 3.2 and 0.5%, respectively. Weight-average molecular weight (MW) of CT ranged from 1483 Da for L. cuneata to 552 Da for L. stuevei. In vitro CH4 production was greatest for L. retusa and A. glabrata at 40.7 mg/g DM and 38.2 mg/g DM, respectively. The least amount of in vitro CH4 was produced by fermentation of two ecotypes of A. angustissima var. hirta, which measured 0.8 and 0.6 mg/g DM, respectively. In vitro CH4 production regressed on CT MW resulted in a R2 of 0.0009 (P = 0.80), strongly suggesting that CT MW does not explain the biological activity of in vitro CH4 production by the forage legumes surveyed. Five of the seven North American native Warm-Season perennial legumes have promise for use in ruminant diets for the purpose of CH4 emission mitigation.
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sustainable low input Warm Season grass legume grassland mixtures mission nearly impossible
Grass and Forage Science, 2011Co-Authors: James P Muir, W. D. Pitman, J L FosterAbstract:Grazing lands in Warm-temperate and subtropical North America have become less diverse. Pastures are typically grass monocultures, while rangelands are generally managed for the grass components. Overstocking, selective herbicides, fire exclusion and heavy rates of nitrogen fertilizer have contributed to near exclusion of native, Warm-Season legumes. The simplicity of managing grass monocultures, pasture production responses to nitrogen fertilizer and profitability of grass-only systems have limited interest in legume-based approaches. Changing economics and ecological concerns with ecosystem accumulation of industrial inputs contribute to an increasing interest in legumes. Unlike the development of temperate pasture legumes and recent research in the tropics, legumes tolerant of both freezing temperatures and hot weather have received less attention. Poor establishment, limited persistence and potential invasiveness limit currently available introduced species. Native, herbaceous, Warm-Season legume species occur throughout Warm-temperate North America, but little attention has been directed to these plants as potential forage species. Some success with a few native legume species, primarily in the genus Desmanthus, suggests potential for expanded assessment of forage value of the many species available. Current assessments of native legumes, primarily for conservation purposes, provide an opportunity to expand evaluations of these species for pasture and rangeland potential while economics of livestock production and public interest in ecosystem health are supportive. Experiences with legumes of Warm-temperate origin in North America, along with results with temperate and tropical pasture legumes globally, provide a starting point for future efforts at incorporating greater legume diversity in pastures and rangelands of subtropical and Warm-temperate regions around the world.
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harvest techniques change annual Warm Season legume forage yield and nutritive value
Agronomy Journal, 2008Co-Authors: James P Muir, Twain J Butler, Richard M Wolfe, John R BowAbstract:Comparison among Warm-Season legume forage trials may not be valid if harvest techniques vary. To address this question, herbage dry matter (DM) yields, branching, crude protein (CP), and fiber concentrations for nine Warm-Season annual herbaceous legumes were measured by hand-plucking all leaves and pliable tips or clipping at 7.5- or 15-cm height. The experiment was conducted in Texas on a Windthorst fine sandy loam over 2 yr. Harvest technique did not affect DM yield in 2004, but the hand-plucked harvest technique produced 34 to 39% less forage in 2005 (low rainfall year) compared with the clipped plots. Most entries had greater branching on hand-plucked than on clipped plants (entry by harvest P < 0.05). Crude protein concentration was greater (P < 0.05) and fiber concentrations lower in the hand-plucked compared with the clipped plants. These results suggest that neither yields nor nutritive values of hand-plucked forage trials examining annual Warm-Season herbaceous legumes should be compared with clipped forage trials, whereas clipping heights may be less problematic. Results support a careful choice of experiment harvest technique based on the future field-scale harvest method or degree of target herbivore selectivity.
R.d. Williams - One of the best experts on this subject based on the ideXlab platform.
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seeding cool Season grasses into unimproved Warm Season pasture in the southern great plains of the united states
Grass and Forage Science, 2008Co-Authors: P W Bartholomew, R.d. WilliamsAbstract:Limited availability of herbage during the cool Season creates a problem of a supply of nutrients for livestock producers throughout the southern Great Plains of the USA and, particularly, on small farms where resource constraints limit possible mitigating strategies. Six cool-Season grasses were individually sown into clean-tilled ground, no-till drilled into stubble of Korean lespedeza [Kummerowia stipulacea (Maxim) Makino] or no-till over-sown into dormant unimproved Warm-Season pastures. The dry matter (DM) yields of mixtures of cool and Warm-Season herbage species were measured to test their potential for increasing cool-Season herbage production in a low-input pasture environment. Only mixtures containing Italian ryegrass (Lolium multiflorum Lam) produced greater year-round DM yields than undisturbed Warm-Season pasture with all establishment methods. When cool-Season grass was no-till seeded into existing Warm-Season pasture, there was on average a 0·61 kg DM increase in year-round herbage production for each 1·0 kg DM of cool-Season grass herbage produced. Sowing into stubble of Korean lespedeza, or into clean-tilled ground, required 700 or 1400 kg DM ha−1, respectively, of cool-Season production before the year-round DM yield of each species equalled that of undisturbed Warm-Season pasture. Productive pastures of perennial cool-Season grasses were not sustained beyond two growing Seasons with tall wheatgrass [Elytrigia elongata (Host) Nevski], intermediate wheatgrass [Elytrigia intermedia (Host) Nevski] and a creeping wheatgrass (Elytrigia repens L.) × bluebunch wheatgrass [Pseudoroegneria spicata (Pursh)] hybrid. Lack of persistence and low productivity limit the usefulness of cool-Season perennial grasses for over-seeding unimproved Warm-Season pasture in the southern Great Plains.
