Metcamifen safeguards fluazifop for the gradual conversion of hybrid bermudagrass fairways to manilagrass

Golf courses throughout the southern United States have begun converting fairways from hybrid bermudagrass ( Cynodon dactylon × C. transvaalensis Burtt‐Davy) to manilagrass [ Zoysia matrella (L.) Merr.]. Recognition (trifloxysulfuron + metcamifen) can be tank‐mixed with fluazifop to gradually remove hybrid bermudagrass during conversion, eliminating the need for glyphosate applications prior to sprigging and reducing disruption of play due to surface imperfections. Trials were conducted in Georgia and Tennessee during the summer of 2022 aimed at chemical plus cultural conversion of TifTuf hybrid bermudagrass fairways to Zorro manilagrass. Treatments consisted of sequential applications of glyphosate + fluazifop (industry standard) and various rates of fluazifop + Recognition applied before and after sprigging. Two applications of glyphosate + fluazifop and three applications of fluazifop + Recognition resulted in days to 80% effective manilagrass conversion (Days 80 ) values of 76–82 days, regardless of rate, while two applications of fluazifop + Recognition resulted in Days 80 values of 88–99 days, regardless of rate. Effective hybrid bermudagrass control (≥90%) was observed 13 weeks after sprigging in response to all treatments in Tennessee, regardless of rate, while a similar trend was observed in Georgia except for two applications of fluazifop + Recognition (47%–78% control). No phytotoxicity was observed on manilagrass throughout each trial. When combined with fluazifop, the inclusion of Recognition provides a non‐phytotoxic option for the gradual conversion of hybrid bermudagrass to manilagrass without disruption in play. Further research should investigate safety of additional manilagrass cultivars and application timings.