Southern Armyworm - Spodoptera eridania (Stoll)

Dr. Phillip Roberts, Extension Entomologist, The University of Georgia, Department of Entomology, Tifton, GA 31793
Dr. Paul Guillebeau, Extension Entomologist, The University of Georgia, Department of Entomology, Athens, GA 30602

Order Lepidoptera: Family Noctuidae

Description: Southern armyworm larvae are gray to nearly black in color. Larvae have a narrow, almost continuous mid-dorsal white stripe and a prominent yellow stripe along each side, interrupted by a black spot on the first abdominal segment, and are marked with yellowish stripes on the back and along each side. Several large spots are present on the segment just behind the third pair of true legs. On small larvae these spots give the appearance of a band around the body. Forewings of the adult are streaked with cream, gray, light brown, and black. The hind wings are white with few dark marks on the margin. Hosts: Sweet potatoes, tomatoes, legumes, cotton, cucurbits, crucifers, and various weeds. Damage: Primarily foliage feeders. Very high infestations may occur in localized spots in a field. Defoliation of plants may occur. Infestations generally occur in the southernmost areas of Georgia.

Southern armyworm immature on cotton leaf Photo by: Eddie McGriff, UGA

Southern armyworm on cotton Photo by: David Jones, UGA

Life Cycle: Moths lay egg masses which are similar to fall or beet armyworm egg masses. However, southern armyworm egg masses are much larger, up to 1 inch in length and 1/2 inch wide. There are four to five generations per year.

Control: Control with insecticides is effective. Generally natural controls will keep populations below economic impact levels. Treat based on a defoliation threshold.

In: Roberts, P. M. and G. K. Douce, Coordinators. 1999. Foliage Feeding Insects. A County Agent's Guide to Insects Important to Agriculture in Georgia. Univ. of GA, Col. Ag. Env. Sci., Coop. Ext. Serv., Tifton, GA USA. Winter School Top Fifty Agricultural Insect Pests and Their Damage Sessions, Rock Eagle 4-H Ctr., Jan. 20, 1999.

Selected References and Suggested Readings