Corn leaf aphid is a sporadic pest of field corn and other field crops in Minnesota. It is an early season pest that migrates into Minnesota from southern overwintering sites. Beneficial insects usually are capable of keeping corn leaf aphids at sub-economic levels, and treatment is seldom necessary. However, damage can be significant in outbreak years, and corn leaf aphid is capable of transmitting several crop diseases.
Aphids give birth to live young.
Nymphs are difficult to distinguish from adults, but are generally smaller and lighter in color. Adult aphids are most often present as wingless adults, though winged forms become more evident as plant development passes the tasseling stage. The winged forms disseminate to form new colonies when environmental conditions are unfavorable or when colonies become overcrowded. Males are seldom seen, and asexual reproduction is the norm. Aphids have a wide host range, but show preferences for barley, sorghum and corn.