The soybean aphid, Aphis glycines Matsumura (Homoptera: Aphidididae) has been found throughout Iowa since 2001, and although recommendations are available, questions regarding what constitutes a best practice for soybean aphid management remain. In 2003 Iowa experienced high populations requiring a transition from post-emergent herbicide to aphid insecticide application. Given this transition, we investigated the importance of modifying pesticide application for optimal A. glycines management. Specifically, do application methods intended to reduce the potential for herbicide drift adversely affect insecticide efficacy. In 2004 we compared the efficacy of a pyrethroid (Warrior, lambda-cyhalothrin) when applied as a herbicide (herbicide best practice ‘HBP’; 20 PSI, 10 GPA, 8001 extended range nozzle) to an insecticide best practice (‘IBP’; 40 PSI, 20 GPA, 11002 twin jet nozzle). Data collected in 2004 from an infested field (250 aphids/plant), indicated that sub-optimal coverage (‘HBP’) allowed aphid populations to persist for a longer period of time, increasing plant exposure to post insecticide-application herbivory. In 2005 we are investigating whether A. glycines will respond to reduced coverage of an organophosphate (Lorsban, chlopyrifos) alone or tank-mixed with a pyrethroid in the same manner as it dose to a pyrethroid alone. If volatilization of organophosphates can compensate for a reduction in coverage, then the ‘HBP’ technique could reduce time spent filling equipment verses the ‘IBP’ technique by reducing the amount of carrier, allowing more acres to be covered in an equivalent time period.