Slender. Young larvae: Creamy white; dark purple band around the body; several brown or purple stripes running lengthwise down the body. Full grown larvae: Creamy white to light purple without band and stripes. Up to 1 and 1/4 inches long when mature.
Common Host Plant(s)
Tomato, corn, pepper and potato.
Eats tunnel in stem, causing plant to wither and die. Tunnel usually has opening up to 1/4 inch in diameter at its lower
Eastern part of United States.
Eggs laid on grassy weeds in late summer or early fall are the overwintering stage of stalk borers. Eggs can be found singly or in groups. Preferred sites for egg laying are often near waterways or field edges, but if fields are overrun with grassy weeds females may deposit eggs throughout the field. In spring the larvae emerge and move to corn as they mature. Larvae experience 7 to 10 instars until full growth is attained in about ten weeks when they enter the soil to pupate. Adult moths appear from August through October. One generation occurs annually.
If one of three plants exhibits stalk borer damage treatment may be warranted. Spot treatment of infested plants may be effective.
Remove and destroy weeds; this insect breeds in weeds. Puncturing the insect may save plant. To locate the borer split the stems lengthwise above opening to tunnel. Bind split stem and keep plant watered. Destroy plants after harvest.
No organic or biological control known for stalk borers.
No chemicals known for control of stalk borer in home gardens.
Virginia Cooperative Extension materials are available for public use, reprint, or citation without further permission, provided the use includes credit to the author and to Virginia Cooperative Extension, Virginia Tech, and Virginia State University.
Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University, and the U.S. Department of Agriculture cooperating. Edwin J. Jones, Director, Virginia Cooperative Extension, Virginia Tech, Blacksburg; M. Ray McKinnie, Administrator, 1890 Extension Program, Virginia State University, Petersburg.
April 25, 2011