Response of Selected Forage Grasses to Herbicides

Abstract

Early spring applications of herbicides were evaluated for weed control and phytotoxicity to kleingrass (Panicum coloratum L.) during establishment. In 1986, areas treated with MSMA (monosodium salt of methylarsonic acid) at 2.2 and 4.5 kg ha−1 or chlorsulfuron {2‐chloro‐N‐[ [(4‐methoxy‐6‐methyl‐1,3,5‐triazin‐2‐yl) amino] carbonyl] benzenesulfonamide} at 0.018 and 0.035 kg ha−1 reduced weed yield to <900 and increased kleingrass yield to >9300 kg ha−1. Untreated areas produced 5400 and 4300 kg ha−1 of weeds and kleingrass, respectively. In 1988, kleingrass yields were increased only where weeds were removed by hand or MSMA. Bensulide [O,Obis( 1‐methylethyl) S‐[2‐[(phenylsulfonyI) amino] ethyl] phosphorodithioate], butylate [S‐ethyl bis(2‐methylpropyl)carbamothioate], siduron [N‐(2‐methylcyclohexyl)‐N'‐phenylurea], and sulfometuron {2‐[[[[(4,6‐dimethyl‐2‐pyrimidinyl) amino] carbonyl] amino] sulfonyl] benzoic acid) were highly injurious to kleingrass. In 1989, no treatment increased kleingrass yields. In the greenhouse, ‘Selection 75’ kleingrass, common buffelgrass (Cenchrus ciliaris L.), ‘WW‐Spar’ and ‘WW‐Ironmaster’ old world bluestem [Bothriochloa ischaemum (L.) Keng var. ischaemum (Hack.) Celarier and Harlan], ‘Bell’ rhodesgrass (Chloris gayana Kunth), ‘Cowboy’ laurisiagrass (Penniseturn orientale L.), ‘Haskel’ sideoats grama [Bouteloua curtipendula (Michx.) Torr.], ‘Lameta’ Indiangrass (Sorghustrum nutans L.), 'Alamo' switchgrass (Panicum virgatum L.), and ‘Palar’ Wilman lovegrass (Eragrosfis superba Peyn.) were treated. Based on seedling weight, most grasses tolerated butylate, MSMA, 2,4‐D [(2,4‐dichlorophenoxy) acetic acid], chlorsulfuron, and metsulfuron {2‐[[[[(4 methoxy‐6‐methyl‐1,3,5‐triazin‐2‐yl)amino] carbonyl] amino] sulfonyl] benzoic acid]. Buffelgrass, Indiangrass, and old world bluestem tolerated sulfometuron. Atrazine [6‐chloro‐N‐ethyl‐N'‐(‐methylethyl)‐ 1,3,5‐triazine‐2,4‐diamine] and propazine [6‐chloro‐N,N'‐ bis(l‐methylethyl)‐l,3,5‐triazine‐2,4diamine] were sometimes injurious, but bensulide and siduron were highly injurious to most grasses.

Effect of Safener, Activated-charcoal Coated Seed, and Charcoal Banding on Establishment of Switchgrass Receiving Pre-emergent Herbicides

“…McMurphy (18) reported that 1.4 lb/acre siduron controlled crabgrass and had no effect on ‘Caddo’ upland switchgrass. However, Bovey and Hussey (6) reported excessive injury to ‘Alamo’ lowland switchgrass at 2 lb/acre siduron. ‘Pathfinder’ upland switchgrass has been reported to tolerate pre‐emergent applications of atrazine, which greatly improves establishment (14,16,17,23).…”

Effects of Seeding Date and Weed Control on Switchgrass Establishment

“…We speculate that 2,4-D injury contributed to the reduction in switchgrass density at the second seeding date in 2008. The potential for warm-season grass injury from 2,4-D and other phenoxy-type herbicides seems to vary, with no injury being reported in some research (Washburn and Barnes 2000) to moderate or severe injury reported elsewhere (Bovey and Hussey 1991;Lair and Redente 2004). These results suggest that preemergence 2,4-D applications to switchgrass could require additional precautions, such as delayed crop planting after application, as is suggested for both corn (Zea mays L.) and soybean (Glycine max L.) (Anonymous 2007).…”

Second biomass conference of the Americas: Energy, environment, agriculture, and industry. Proceedings

“…'Alamo' switchgrass, in a greenhouse study, was tolerant to bensulide, MSMA and metsulfuron but was injured by triazines, 2,4-D, and siduron (Bovey, 1991).…”