| Abstract/Contents: | "No herbicides are currently registered for preemergence weed control in seeded centipedegrass (Eremochloa ophiuroides) at the time of planting. Herbicide recommendations during the establishment of centipedegrass state to use one-half the recommended rate of pre- or postemergence herbicide after seedlings have emerged. Reduced rates of the postemergence herbicides are not always effective and can injure the grass seedlings if applied when the seedlings are too small. Since the centipedegrass seed needs 14 to 21 days to germinate, weeds usually outgrow the centipedegrass seedlings. A series of studies were initiated to evaluate registered and experimental herbicides for postemergent weed control and crop tolerance in seeded centipedegrass. Herbicides evaluated included atrazine, bromoxynil, imazameth, imazethapyr, metsulfuron, halosulfuron, bentazon, chlorimuron, imazaquin, acifluorfen, XRM 5084, fomesafen, lactofen, mecoprop + 2,4-D + dicamba, and clopyralid + triclopyr. Predominant weeds in the test area were rice flatsedge (Cyperus iria), annual sedge (C. compressus), Virginia buttonweed (Diodia virginiana), doveweed (Murdannia nudiflora), leafflower (Phyllanthus urinaria), and hurricanegrass (Fimbristylis spathacea). Significant injury to the centipedegrass occurred with acifluorfen, fomesafen, and lactofen at two weeks after treatment. At four weeks after treatment most of the injury had disappeared. The following weed control data are based on evaluations made four to six weeks after treaatment. Rice flatsedge was controlled by all herbicide treatments. Annual sedge was controlled by chlorimuron, halosulfuron, triclopyr + clopyralid, imazameth, XRM 5084 at 1.0 lb/A, atrazine at 4.0 lb/A, and acifluorfen at 1.0 lb/A. Leafflower was controlled by imazaquin, triclopyr + clopyralid, imazameth, metsulfuron, XRM 5084, and atrazine. Most effective control of Virginia buttonweed occurred with treatments of atrazine at 4.0 lb/A, triclopyr + clopyralid at 1.5 lb/A, metsulfuron at 0.037 lb/A, and XRM 5084. Hurricanegrass was controlled by chlorimuron, halosulfuron, and bromoxynil. Doveweed was not controlled by any herbicide treatment." |
|---|
