Corn earworm
Helicoverpa zea (Boddie)
(Insecta: Lepidoptera: Noctuidae)
Adult moths have highly variable color patterns. Forewings are yellowish brown with reddish brown, olive green, or gray markings. Hind wings are creamy white at the base and dark gray distally. All four wings usually show a small, dark, central spot. Wingspan measures 32 to 45 mm. Larvae also vary in color. Their heads are orange or light brown and their thoracic plates are black. Bodies may be yellow, green, pink, brown or almost black, laterally bearing a dark brown band above and a yellowish white band below the spiracles. Larval length ranges from 1.5 mm (first instar) to 24.8 mm (sixth instar). Pupae are mahogany brown, 17 to 22 mm long, and 5.5 mm wide.
Adults live 15 to 30 days, and one female may lay up to 35 pale green eggs per day. Larvae hatch within three to four days, each instar lasts about two to four days, and the pupal stage lasts on average 13 days. The life cycle can be completed in 30 days. Northern geographical regions support one generation, but tropical and subtropical climates allow continuous activity with up to seven generations per year.
Corn earworm is highly dispersive and occurs throughout North America except for Alaska and northern Canada, although it may not overwinter in the northern areas.
Helicoverpa zea is highly polyphagous. Corn, sorghum and tomato are preferred hosts, but numerous vegetable, field, and fruit crops frequently are damaged by corn earworm larvae. In addition, adults feed on nectar from many tree and shrub species.
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Eggs of corn earworm, Helicoverpa zea (Boddie)
(Photographer: James Castner, University of Florida)
Larva of corn earworm, Helicoverpa zea (Boddie), feeding on corn
(Photographer: Lyle Buss, University of Florida)
Adult moth of corn earworm, Helicoverpa zea (Boddie), with spread wings
(Photographer: Lyle Buss, University of Florida)
Adult moth of corn earworm, Helicoverpa zea (Boddie)
(Photographer: James Castner, University of Florida)