Abstract
Root growth of three zoysia (Zoysiaspp. ‘Emerald’, ‘Meyer’, and ‘Matrella’) cultivars and four bermudagrasses [Cynodon dactylon(L.) Pers. ‘Tifway’, ‘Tifgreen’, ‘Tifdwarf’, and ‘Ormond’] was determined after several consecutive annual herbicide treatments. Napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide] reduced the root growth of all zoysia and bermudagrass cultivars. Prosulfalin {N-[[4-(dipropylamino)-3,5-dinitrophenyl] sulfonyl]-S,S-dimethylsulfilimine} retarded root growth of Tifgreen and Tifdwarf bermudagrass when treated at any rate. Tifway and Ormond bermudagrass and zoysia cultivars were retarded at the 3X rate (10.2 kg/ha). Zoysia grass roots were not affected by oxadiazon [2-tert-butyl-4-(2,4-dichloro-5-isopropoxyphenyl)-δ2-1,3,4-oxadiazolin-5-one], bensulide [O,O-diisopropyl phosphorodithioateS-ester withN-(2-mercaptoethyl)benzenesulfonamide], or benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine) treatments. DCPA (dimethyl tetrachloroterephthalate) and oxadiazon did not reduce root growth of bermudagrasses, except when Tifgreen was treated with oxadiazon at 3X rate (13.4 kg/ha).