Potential Use of Metamifop for Weed Control In Turfgrass.

Metamifop is an aryloxyphenoxypropionate herbicide that controls various turfgrass weeds including barnyardgrass (Echinochloa crus-galli), crabgrasses (Digitaria spp.), and goosegrass (Eleusine indica). Research was conducted to evaluate the response of bermudagrass (Cynodon dactylon x C. transvaalensis), bentgrass (Agrostis stolonifera), crabgrass (Digitaria spp.), dallisgrass (Paspalum dilatatum), tall fescue (Festuca arundinacea), Kentucky bluegrass (Poa pratensis), seashore paspalum (Paspalum vaginatum), and zoysiagrass (Zoysia matrella) at the Auburn University Turfgrass Research Unit in Auburn, AL and FarmLinks golf course in Sylacauga, AL. Treatments included metamifop applied up to 0.8 kg ai/ha, a nontreated check, and relevant standard herbicide comparisons. Results indicate that metamifop is safe to cool-season turfgrasses including bentgrass, tall fescue, and Kentucky bluegrass. However, metamifop is injurious to warm-season turfgrasses including bermudagrass and seashore paspalum, but safe to zoysigrass. Metamifop may be useful to control crabgrass in the early postemergence stage, but the herbicide does not adequately control dallisgrass. Therefore metamifop may have a role of suppressing or controlling warm-season grasses in cool-season grasses as well as controlling certain weeds.