Abstract/Contents: | "Trials were conducted to evaluate postemergence applications of trifloxysulfuron (Monument 75WG), foramsulfuron (Revolver), rimsulfuron (TranXit GTA), and metsulfuron (Manor) for their effects on winter annual, and cool and warm season perennial broadleaf weeds in warm season turfgrass stands. Trials were initiated in July 2000 on Virginia buttonweed (Diodia virginiana), March 2003 on corn speedwell (Veronica arvensis), June 2003 on wild violet (Viola sp.), and November or December 2003 on Carolina geranium (Geranium carolinianum), henbit (Lamium amplexicaule), ivyleaf speedwell (Veronica hederifolia), lawn burweed (Soliva pterosperma), and white clover (Trifolium repens). In 2004, trials were initiated in January on lawn burweed, and March or April on catsear dandelion (Hypochoeris radicata), common chickweed (Stellaria media), corn speedwell, facelis (Facelis retusa), field pansy (Violarafinesquii Greene), lawn pennywort (Hydrocotyle sibthorpioides), mouseear chickweed (Cerastium vulgatum), and yellow woodsorrel (Oxalis stricta). Trifloxysulfuron was applied at 0.33 ounces of product per acre (oz/A) with the following exceptions; 0.47 oz/A 2X on Virginia buttonweed, 0.47 oz/A 1X on 2004 lawn burweed and wild violet, 0.56 oz/A on Carolina geranium and lawn pennywort, and 0.59 oz/A on 2003 corn speedwell. The foramsulfuron rate was 17 fluid ounces of product per acre (fl oz/A) on all weed species tested. Rimsulfuron was applied at 1 oz/A with the following exceptions; 2 oz/A on Carolina geranium, 2003 corn speedwell, henbit, ivyleaf speedwell, and white clover. Metsulfuron was applied at 0.5 oz/A with the following exceptions; 0.33 oz/A on catsear dandelion, 0.75 oz/A on wild violet, and 1 oz/A on 2003 corn speedwell, and Virginia buttonweed. All treatments except foramsulfuron received a nonionic surfactant at 0.25% (v/v). Winter weed percent control data are presented from late season evaluations in April or May of 2003 or 2004, before weed death or dieback. Summer weed percent control data for Virginia buttonweed are from evaluations 12 and 62 WAT. Wild violet percent control data are from 9 WAT evaluations. Catsear dandelion and lawn pennywort percent control data are from evaluations 8 WAT. Trifloxysulfuron provided 99 to 100% control of common chickweed, 2004 corn speedwell, henbit, ivyleaf speedwell, lawn burweed, lawn pennywort, mouseear chickweed, and white clover. Two 0.33 oz/A applications at 4-wk intervals were needed for total lawn pennywort control. Trifloxysulfuron provided excellent control (94 to 97%) of 2003 corn speedwell, lawn pennywort, and Virginia buttonweed (12 WAT). 94% lawn pennywort control was achieved with a single application at 0.56 oz/A. Two applications of trifloxysulfuron were needed at 0.47 oz/A each for 97% Virginia buttonweed control. At 62 WAT, Virginia buttonweed control was 93%. Field pansy was controlled 79% with 0.33 oz/A of trifloxysulfuron. Trifloxysulfuron provided no control of Carolina geranium or facelis. Foramsulfuron provided total control of henbit. Common and mouseear chickweed were controlled 62 and 81%, respectively. Foramsulfuron provided 61% lawn burweed control when applied in November 2003 when weeds were young and actively growing. No control was observed on lawn burweed when applied in January 2004. Foramsulfuron provided poor control (9 to 26%) of field pansy, white clover, and wild violet. No control was observed on Carolina geranium, corn speedwell, facelis, and ivyleaf speedwell. Rimsulfuron completely controlled common chickweed, henbit, lawn burweed treated in November 2003, and mouseear chickweed. 98% control occurred on lawn burweed treated in January 2004. Poor control (3 to 23%) was achieved with 2 oz/A rimsulfuron on 2003 corn speedwell, and 1 oz/A on field pansy and wild violet. Rimsulfuron did not affect Carolina geranium, 2004 corn speedwell, facelis, ivyleaf speedwell, or white clover. Metsulfuron provided 99 to 100% control of Carolina geranium, catsear dandelion, common chickweed, facelis, field pansy, henbit, ivyleaf speedwell, mouseear chickweed, white clover, wild violet, and yellow woodsorrel. Excellent control (93%) was observed on lawn pennywort. Virginia buttonweed control at 12 WAT was 75% with 1 oz/A metsulfuron, dropping to 61% at 62 WAT. Metsulfuron controlled corn speedwell only 33% in 2003 when applied at 1 oz/A and 0% in 2004 when applied at 0.5 oz/A. These data suggest that recently registered sulfonylurea herbicides , though they target annual bluegrass control and perennial ryegrass removal, can possibly be incorporated into a total grass and broadleaf weed management program, solving multiple weed problems with a single application." |