Multiple Herbicide Treatments for Grassy Weed Control in Turf

Abstract

Two applications of benefin (N-butyl-N-ethyl-α,α,α,-trifluoro-2,6-dinitro-p-toluidine), profluralin [N-(cyclopropylmethyl)-α,α,α-trifluoro-2,6-dinitro-N-propyl-p-toluidine], prosulfalin N-[[4-(dipropylamino)-3,5-dinitrophenyl]sulfonyl]-S,S-dimethylsulfilimine, and napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide] provided full-season large crabgrass [Digitaria sanguinalis (L.) Scop.] control in turfgrass. Benefin was applied at 3.3 kg/ha in March and 2.2 kg/ha in May while other herbicides were applied at 2.2 kg/ha in March and May. Satisfactory goosegrass [Eleusine indica (L.) Gaertn.] control was obtained with a single March treatment with prosulfalin, but two applications of napropamide in March and May were required for similar control. None of the herbicide treatments severely injured common bermudagrass [Cynodon dactylon (L.) Pers.] or Kentucky bluegrass [Poa pratensis (L.) ‘Common’] in these studies. Prosulfalin at 6.6 kg/ha applied as single treatment or 3.3 kg/ha in each of two applications resulted in moderate injury to Kentucky bluegrass in 1 of 2 yr.