| Abstract: | In the climatic transition zone and especially in the piedmont region of Virginia, cool-season grasses have been primarily used for sports turf in the past due to poor winter survival of warm-season grasses. However, new seeded bermudagrass (SB) varieties promise to replace cool-season turf in these areas because they tolerate cold temperatures and make renovating damaged sports turf easier than sprigging. Previous studies have evaluated the use of various chemicals both pre- and postemergence on sprigged bermudagrass establishment, however few studies provide herbicide options for control of troublesome weeds during SB establishment. Field studies were conducted to evaluate Riviera SB response to foramsulfuron and flazasulfuron applied before and after seeding. Excluding the highest rate applied 1 wk after seeding, foramsulfuron at 0.029, 0.057, and 0.086 kg ai/ha applied 2 wk before seeding, at seeding, and 1, 2, and 4 wk after seeding did not injure SB or decrease green cover. In contrast, flazasulfuron at 0.027 and 0.053 kg ai/ha severely injured bermudagrass when applied 4, 2, 1, and 0.5 wk before seeding and 0.5, 1, and 2 wk after seeding but not 4 wk after seeding at the low rate. Data suggests that foramsulfuron can be applied anytime except 1 wk after seeding but flazasulfuron should not be applied within 4 wk of seeding. |