What's eating my corn?

Corn earworm is the single most destructive pest of corn, tunnelling directly into the silk and kernel tip of every ear. Fall armyworm and European corn borer also bore into stalks and ears. Aphids colonise tassels. Birds and raccoons raid ripe ears. Physical barriers and timely Btk applications are key.

Larvae tunnel into silk and feed down through kernels at the ear tip; frass and chewed kernels visible when husked Apply mineral oil with a dropper to silk tips 3–5 days after silk emergence; Btk or spinosad sprayed on silks every 3–4 days; pheromone traps to monitor adult moths

Ragged holes in whorls of young plants; sawdust-like frass in the whorl; stripped tassels and silk on older plants Btk or spinosad applied into the whorl; beneficial nematodes in soil; monitor with pheromone traps; early planting avoids peak pressure

Dense bluish-green colonies on tassels and upper leaves; honeydew stunts pollination; sooty mould reduces photosynthesis Tolerate light infestations (natural enemies usually catch up); insecticidal soap for heavy colonies; avoid excessive nitrogen which fuels aphid outbreaks

Ears stripped and husks torn back; kernels removed or scattered; damage occurs overnight near harvest Electric fencing around the corn block; paper bag ear covers; harvest promptly at peak maturity; motion-activated deterrents