The maggots are yellowish-white, ~ 1/4" long, sharply pointed at the head end, legless, and tough-skinned.

Maggots feed inside the kernel; either the seed fails to germinate, or the seedling is weak.

April and May (statewide)

Check for seeds in soil after planting. Dig two linear feet of row in five locations where skips in seedling stand occur. Examine seed for maggots and feeding damage.

Not available. If damage is severe early, replanting may be necessary.

http://www.unl.edu/entomology/extension/crops/fieldcorn.shtml