The soybean aphid is an invasive insect pest that threatens the stability of the current soybean management system in Indiana. During the past six years, researchers at Purdue University have documented the impact of soybean aphids on soybean yield, identified key natural enemies of the aphid, found overwintering hosts and contributed to the development of management options including an economic threshold, sampling methods and Extension materials .

Researchers have noted that outbreak years (2001, 2003 and 2005) have been followed by years of low aphid densities (2002, 2004 and 2006). This is seen both by scouting aphids in soybean fields and in suction traps that collect flying (migrating)...