Impact of different insecticides grouped by mode of action on (a) plant exposure to soybean aphids and (b) yield. Foliar insecticides were applied on August 2, 2005. Means labeled with a unique letter were significantly different (p = 0.05). *Lorsban® + Baythroid® is a tank mix consisting of an organophosphate (Lorsban®) and a pyrethroid (Baythroid®). (SEM = standard error of the mean.)