Corn Earworm

Cotton Bollworm

Sorghum Headworm

Tomoto Fruitworm


Helicoverpa zea

Corn Earworm larva on an ear of corn
Corn Earworm larva on an ear of corn. Photo courtesy of R.L. Croissant. Licensed under CC BY 3.0.
Corn earworm larva feed on a large number of crops, including corn, tomatoes, and cotton making them a significant pest. They overwinter in the southern U.S. and migrate each summer into the north as far as Canada.
Adults range in color from green to brown and have a wing span of 1-1.5".
Corn Earworm adult on peanut
Corn Earworm adult on a peanut plant. Photo courtesy of Scott L. Brown. Licensed under CC BY 3.0.
The larva have a broad range of colors from light brown or pink to dark green or brown. The head is orange or light brown which distinguishes it from similar larva.
Corn Earworm larva on an ear of corn
Corn Earworm larva. Photo courtesy of cyanocorax. Licensed under CC BY-SA 2.0.
Small light-colored flattened spheres which are laid singly on leaves or silks and have a reddish brown ring at the top.
Corn Earworm eggs
Corn Earworm eggs. Photo courtesy of USGS Bee Inventory and Monitoring Lab from Beltsville, Maryland, USA. Licensed under CC BY 2.0.
Corn Earworm larva directly attack ear/fruit, resulting in yield losses and making fresh market produce unmarketable. They are cannibalistic and so typically only one larva will be found at a feeding site.
Several insecticides are available for controlling Corn Earworm, although it has developed resistance to many kinds. Timing is crucial since the larva is protected once it burrows into the ear or fruit. Always read and follow all label instructions.
Some Bt corn hybrids provide partial protection against corn earworm, although the pest has developed resistance to some strains and so protection varies.