Corn Earworm / Borer (2026)
Corn, tomato, beans
Quick answer: Corn Earworm / Borer attacks corn, tomato, beans. Start with the organic/IPM steps below; use the chemical option only if damage escalates, and always follow the product label. Early planting; resistant varieties; destroy stalks in fall.
Your Corn Earworm / Borer IPM card
Select your state to see whether this pest is common there, then print.
Corn Earworm / Borer in Iowa: Listed among the most-reported pests in your state — watch for it.
Corn Earworm / Borer
Targets
Corn, tomato, beans
Signs
Holes in ears or stems; frass at entry.
Organic / IPM first
Bt (kurstaki) sprays; mineral oil on silk; crop rotation.
Chemical option (follow label)
Spinosad or pyrethroid at tassel stage.
Prevention
Early planting; resistant varieties; destroy stalks in fall.
Corn Earworm / Borer by host plant
Host-specific signs and control — see the full pest × host reference.
More pests
Treatments follow integrated pest management (IPM): identify first, least-toxic fix second. Product specifics and labels vary by state — confirm with your county extension.