Mature goosegrass (Eleusine indica) control in bermudagrass (Cynodon dactylon) turf with a metribuzin-diclofop combination

Field studies were conducted to determine if metribuzin-diclofop combinations could provide selective control of mature goosegrass in common bermudagrass turf. In two field trials, diclofop at 1.7 kg ai/ha provided 19% control of mature goosegrass at 7 wk after treatment (WAT), whereas metribuzin at 0.28 or 0.56 kg ai/ha controlled 30 and 53%, respectively. When diclofop at 1.7 kg/ha was combined with metribuzin at 0.28 or 0.56 kg/ha, goosegrass control increased to 68 and 90%, respectively. That degree of mature goosegrass control with a single application of metribuzin at 0.56 kg/ha plus diclofop at 1.7 kg/ha was equivalent to metribuzin at 0.56 kg/ha plus MSMA at 2.2 kg ae/ha followed by MSMA at 2.2 kg/ha 1 wk later. The metribuzin-diclofop combination injured common bermudagrass turf less than or equivalent to the metribuzin-MSMA combination. The injury was transitory; at 3 WAT, none of the treatments injured common bermudagrass.