Control of Tall Fescue in Kentucky Bluegrass Turf with Selective Herbicides

Abstract

Chlorsulfuron, diclofop, and sulfometuron were evaluated for potential use in selective control of tall fescue (Festuca arundinacea Schreb.) in Kentucky bluegrass (Poa pratensis L.). Polynomial trend analyses indicated highly significant linear and quadratic response curves for percentage of tall fescue reduction for each herbicide. Fall and spring treatments with chlorsulfuron and diclofop provided significant tall fescue control, with slight to moderate initial Kentucky bluegrass phytotoxicity. Fall and spring applications of sulfometuron resulted in excellent tall fescue control, but initial Kentucky bluegrass damage was severe and would be unacceptable for high maintenance turf. Chemical names used: 2-chloro- N -[[(4-methoxy-6-methyl-l,3,5-triazin-2-yl)amino]carbonyl]-benzenesulfonamide (chlorsulfuron); 2-[4-(2,4-dichlorophenoxy)phenoxy]proponoate (diclofop); N -[[(4,6-dimethylpyrimidin-2-yl)amino]carbonyl]-2-methoxycarbonyl-benzenesulfonamide (sulfometuron).