Establishment of Kentucky bluegrass and tall fescue seeded after herbicide application

Abstract

AbstractWeed control before seeding is often required for successful turfgrass establishment, since weed interference prior to turfgrass tillering causes a reduction of cover and density. However, herbicides differ widely in the delay required after herbicide application before seeding can occur without injury to seedlings. The objective of this research was to determine the influence of three selective postemergence grass, broadleaf, and sedge herbicides on the cover and density of Kentucky bluegrass (Poa pratensis L.) and tall fescue (Schedonorus arundinaceus Schreb.) seeded 0, 3, 7 or 14 d after herbicide application. Herbicide treatments included: an untreated control, 2,4‐D + 2‐(2‐methyl‐4‐chlorophenoxy)propionic acid (MCPP) + dicamba (1.64 lb acid equivalent acre–1), quinclorac (0.75 lb a.i. acre–1), halosulfuron‐methyl (0.06 lb a.i. acre–1), and dithiopyr (0.50 lb a.i. acre–1), which was included for comparison. Seeding between 0 to 14 d after an application of 2,4‐D + MCPP + dicamba or quinclorac had little or no effect on Kentucky bluegrass or tall fescue cover in Manhattan, KS, and Wooster, OH. Halosulfuron‐methyl reduced the cover of both turfgrass species when seeded 0 or 7 d after application. This research demonstrates that turfgrass managers who unknowingly seed into areas treated with 2,4‐D + MCPP + dicamba or quinclorac within 0 to 14 d after treatment are likely to observe successful establishment of Kentucky bluegrass or tall fescue under the conditions evaluated in these experiments.