Tolerance of black, cranberry, kidney, and white bean to cloransulam-methyl

The level of tolerance of various market classes of dry bean to cloransulam-methyl is not known. Three field studies were conducted in Ontario, Canada during 2007 and 2008 to determine the level of tolerance of black, cranberry, kidney, and white bean to the pre-emergence (PRE) and postemergence (POST) application of cloransulam-methyl at 17.5, 35, and 70 g ai ha^?1. Cloransulam-methyl applied at 17.5, 35, and 70 g ha^?1 caused between 13 and 23% injury in black, cranberry, kidney, and white bean, respectively. Cloransulam-methyl applied at 17.5, 35, and 70 g ha^?1 reduced the shoot dry weight by between 16 and 28% compared to the untreated control. Cloransulam-methyl applied PRE reduced the height of black bean by 27% and the height of cranberry bean by 25% at 70 g ha^?1 and reduced the height of white bean by 19% at 35 g ha^?1 and by 37% at 70 g ha^?1. Cloransulam-methyl applied PRE reduced the yield of black bean by 29% at 35 g ha^?1 and by 43% at 70 g ha^?1, reduced the yield of cranberry bean by 43% at 70 g ha^?1, and reduced the yield of white bean by 36% at 35 g ha^?1 and by 54% at 70 g ha^?1. Based on these results, there is not an adequate margin of crop safety for the PRE and POST application of cloransulam-methyl in black, cranberry, kidney, and white bean at the rates evaluated.