Experiments were conducted from 2003 through 2006 to compare annual grass control by graminicides applied alone or with other pesticides and to determine whether graminicide formulation affected annual grass control and interactions with co-applied pesticides. Formulation and rate had no affect on broadleaf signalgrass or large crabgrass control by clethodim. The efficacy of clethodim in tank mixtures with acifluorfen plus bentazon, bentazon, chlorothalonil, imazapic, pyraclostrobin, or tebuconazole were not affected by clethodim formulation. Broadleaf signalgrass and large crabgrass control by clethodim was slightly reduced by acifluorfen plus bentazon, chlorothalonil, imazapic, and pyraclostrobin, but not by tebuconazole. Chlorothalonil and pyraclostrobin reduced broadleaf signalgrass control with quizalofop-P but did not reduce fall panicum control. Azoxystrobin, propiconazole, and tebuconazole did not affect efficacy of quizalofop-P.

Nomenclature: Acifluorfen; azoxystrobin, methyl (E)-[2-[2-6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl]-3-methoxyacrylate; bentazon; chlorothalonil, tetrachloroisophthalonitrile; clethodim; imazapic; propiconazole, 1-[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl-methyl]-1H-1,2,4-triazol; pyraclostrobin, carbamic acid, [2-[[[1-(4-chlorophenyl)pyrazol-3-yl]oxymethyl]phenyl]methoxy-, methyl ester; quizalofop-P; sethoxydim; tebuconazole, α-[2-(4-chlorophenyl)ethyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol; broadleaf signalgrass, Urochloa platyphylla (Nash) R.D. Webster UROPP; fall panicum, Panicum dichotomiflorum Michx. PANDI; large crabgrass, Digitaria sanguinalis (L.) Scop. DIGSA