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.
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 end.
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. Plant may be saved by puncturing the insect. 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.
Notice: Because pesticide labels can change rapidly, you should read the label directions carefully before buying and using any pesticides. Regardless of the information provided here, you should always follow the latest product label when using any pesticide. If you have any doubt, please contact your local Extension agent or pesticide dealer for the latest information on pesticide label changes.
Disclaimer: Commercial products named on this site are for informational purposes only. Virginia Cooperative Extension does not endorse these products and does not intend discrimination against other products which also may be suitable.
Prepared by Alexandra Spring and Eric Day (Modified from a publication by the USDA)