Pre-Emergent Goosegrass Control in Common Bermudagrass with Flumioxazin.

Goosegrass (Eleusine indica (L.) Gaertn.) is problematic summer annual weed in both cool season and warm season turfgrass. Recently, flumioxazin was registered for use in dormant bermudagrass (Cynodon dactylon (L.) Pers).  Flumioxazin inhibits protoporphyrinogen oxidase enzyme and it can be utilized for pre- and post-emergence weed control. Dormant turf application of flumioxazin has exhibited efficacy for post-emergence winter annual weed control and pre-emergence summer annual weed control.  The objective of this study was to evaluate flumioxazin for its pre-emergent control of goosegrass in common bermudagrass.  This study was conducted at Cimarron Trails Golf Course in Perkins, OK.  Seven herbicide treatments, including flumioxazin, indaziflam, prodiamine, and oxadiazon, were applied to dormant common bermudagrass.  All treatments included a non-ionic surfactant as 0.25 % V/V. Applications were applied using a CO₂ pressurized R&D Brand bicycle sprayer. The sprayer utilized a 1.5 m wide boom with three Spraying System TeeJet 8002 VS nozzles and 1.5 m x 3 m plots were assigned in a randomized complete block design with 4 replications. Treatment applied to this study did not delay bermudagrass green-up in spring 2013 and there was no significant herbicide injury observed in all plots.  On the first rating date (26 weeks after initial treatment), all flumioxazin treatments showed significantly less goosegrasses on the plots. There was no significant difference between sequential flumioxazin treatments and indaziflam on all rating dates. Compared with prodiamine and oxadiazon, flumioxazin treatments maintained greater goosegrass control throughout this study.