Lima bean cultivar ‘Improved Kingston’ was evaluated for sensitivity to herbicide treatments in a field experiment, conducted from 1999 to 2001 in Ontario. Crop was evaluated for visual injury at 7, 14, and 28 d after emergence following preemergence (PRE) applications of metolachlor (1,600 and 3,200 g ai/ha) and imazethapyr (75 and 150 g ai/ha). Crop visual injury to postemergence (POST) applications of imazamox + fomesafen (25 + 200 g ai/ha and 50 + 400 g ai/ha) and quizalopfop-P (72 and 144 g ai/ha) was evaluated at 7, 14, and 28 d after treatment. Plant height and crop yield were also assessed. The imazamox + fomesafen mixture caused significant visual injury and tended to decrease lima bean height and yield. Despite some initial injury observed in the metolachlor, imazethapyr, and quizalofop-P treatments, yield was not significantly decreased. Because of their margin of crop safety, metolachlor applied PRE at 1,600 g/ha, imazethapyr applied PRE at 75 g/ha, and quizalofop-P applied POST at 72 g/ha have excellent potential as weed management tools in Ontario lima bean production.
