Mature Goosegrass (Eleusine indica) Control in Bermudagrass (Cynodon dactylon) Turf with a Metribuzin–Diclofop Combination

Abstract

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.