EFFECT OF TRIFLOXYSULFURON SODIUM RATE AND SEQUENTIAL TREATMENTS ON TRANSITION OF OVERSEEDED BERMUDAGRASS FAIRWAYS

摘要

Three field studies were conducted during 2001 and 2002 on two Virginia golf course fairways near Keswick and Forest,VA to evaluate trifloxysulfuron sodium for control of overseeded perennial ryegrass (Lolium perenne) and effects on bermudagrass (Cynodon dactylon) during spring transition.Trifloxysulfuron sodium completely controlled perennial ryegrass without slowing bermudagrass greenup when applied once at 25 g ai/ha or twice at 12 g ai/ha.When applied twice at 6 g ai/ha trifloxysulfuron sodium controlled perennial ryegrass at a speed comparable to pronamide,but late season control was not complete.All treatments increased turf quality compared to the nontreated check by 8 weeks after initial treatment (WAIT).Trifloxysulfuron sodium applied once at 37 g ai/ha or twice at 25 or 37 g ai/ha rapidly controls perennial ryegrass,but may temporarily slow bermudagrass post-dormancy transition.Trifloxysulfuron sodium applied once at 25 g ai/ha is better for rapid perennial ryegrass control and trifloxysulfuron sodium applied twice at 6 to 12 g ai/ha is better for slower perennial ryegrass control.Turfgrass quality was affected in plots receiving trifloxysulfuron sodium at higher rates than lower rates in 2001,but not in 2002 due to temperature differences between years.