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1	Herbicide Safening to Aid in the Establishment of Three Native Warm Season Grass Species Smith, Jesse Spencer 17 May 2014 (has links) Difficulties with stand establishment are a major factor limiting further agronomic use of native warm season grasses. One significant cause of stand failure is competition with rapidly growing annual weed species during the early development of the perennial native grass. Broad spectrum preemergent herbicides can provide the needed weed control, but only if tolerance exists in the desired grass. Herbicide safeners, synthetic compounds that protect crops from herbicide injury, applied as seed treatments offer a potential strategy to achieving the needed herbicide tolerance where it does not naturally occur. This study tested the efficacy of five herbicide safeners (benoxacor, fenclorim, fluxofenin, naphthalic anhydride, and oxabetrinil) in protecting three native warm season grass species (big bluestem, Andropogon gerardii Vitman; little bluestem, Schizachyrium scoparium (Michx.) Nash; indiangrass, Sorghastrum nutans (L.) Nash) from herbicidal injury caused by preemergent application of S-metolachlor and quantifies this establishment method’s impact on early stand performance. metolachlor benoxacor fenclorim fluxofenin oxabetrinil naphthalic anhydride big bluestem little bluestem indiangrass
2	Growth Response of Mixed Native Grass Stands to Simulated Grazing In Mississippi: Forage Yield and Species Dynamics Temu, Vitalis Wilbald 06 August 2011 (has links) Some native warm-season forage grasses [indiangrass (IG, Sorghastrum nutans), big bluestem (BB, Andropogon gerardii) and little bluestem (LB, Schizachyrium scoparium)] are gaining popularity for improving summer forage production and wildlife habitat in the southeastern USA. Paucity of information about appropriate harvest management limits their restoration success. An experiment was conducted to assess effects of harvest intervals (30-, 40-, 60-, 90 or 120-d) and harvest duration on forage yield and quality, plant growth, sward structure and botanical composition of their mixed stands at Bryan Farms, Clay County, MS. Total season forage was greatest for 30-d and more from first (8472 kg ha-1) than second year plots (7627 kg ha-1). Yield was reduced by up to 43% in the second harvest year. Forage quality (crude protein content and in vitro digestibility) decreased with lengthening of harvest interval and across the harvest season. Tiller weight increased while specific leaf area and relative growth rate decreased with lengthening of harvest interval in first and second year plots. Harvesting reduced sward heights the following May, but treatment did not affect sward heights. Season mean sward heights were shorter for short harvest intervals. Light interception was greatest in the control and decreased with shortening of harvest intervals. Continuous harvesting controlled Solidago canadensis, increased herbaceous forbs, and LB, but decreased IG without substantial effect on BB. Rotational harvesting at 30- or 40-d intervals may improve forage production without compromising breeding cover during recovery. Studies on other management practices including fertilizer application and timing of harvest are needed. cover composition digestibility fiber crude protein growth rate Forage warm-season grass defoliation frequency harvest sward stand height. leaf area assimilation ground-nestig wildlife habitat recovery summer harvest little bluestem big bluestem indiangrass canopy

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Herbicide Safening to Aid in the Establishment of Three Native Warm Season Grass Species

Growth Response of Mixed Native Grass Stands to Simulated Grazing In Mississippi: Forage Yield and Species Dynamics