Combined impact of aerification, postemergence herbicides, and post-herbicide irrigation on goosegrass control in bermudagrass putting greens

Abstract

Goosegrass [Eleusine indica (L.) Gaertn.] is a difficult-to-control grassy weed occurring in compacted soils or heavy-traffic areas including golf greens. In Florida, goosegrass survives as a short-lived perennial, and eradication becomes more challenging as the plant matures. Currently, only foramsulfuron (FOR) is registered for postemergence goosegrass control in hybrid bermudagrass [Cynodon dactylon (L.) Pers. × Cynodon transvaalensis Burtt-Davy] putting surfaces. A 2-year study evaluated the impact of three aerification treatments (none vs. once year⁻¹ or twice year⁻¹) followed by herbicide applications (FOR at 0.029 kg ha⁻¹, simazine at 0.525 kg ha⁻¹, metribuzin at 0.210 kg ha⁻¹, topramezone [TOP] at 0.006 kg ha⁻¹, and mesotrione [MES] at 0.175 kg ha⁻¹) to control mature goosegrass in a TifEagle hybrid bermudagrass putting green in Davie, FL. The impact of immediate post-herbicide irrigation on turf safety was also investigated. Aerification treatments were initiated in June, and herbicides were applied approximately 1 week after each aerification event. FOR did not effectively control goosegrass, while tank-mixes of mesotrione + topramezone tank-mix and simazine + mesotrione tank-mix provided effective control but produced unacceptable phytotoxicity. Post application irrigation reduced turf injury with TOP and MES alone in 2021, and weed control in both years. Aerification did not influence goosegrass control or turf safety.