Postemergence applications of nicosulfuron and primisulfuron were compared to preplant glyphosate and atrazine plus simazine for quackgrass control in reduced tillage and no-till corn. The level of quackgrass control was reduced by no-till practices. At 6 wk after planting, glyphosate and atrazine plus simazine were most effective in controlling quackgrass. Quackgrass biomass 12 wk after planting indicated that the performance of the herbicides were generally similar, although primisulfuron was less effective in no-till. One year after corn planting, levels of quackgrass control in the tilled plots were the same as or better than in the no-till treatments. Atrazine plus simazine was the most effective herbicide treatment over tillage systems, while primisulfuron was the least effective.
