The caterpillars vary from the usual yellowish green to dull red. Mature larvae are about 1.5 inches long, with a narrow white line down the center of the back and two broader yellowish lines along the sides. The head is amber with a light and dark stripe on each side.
Hosts include several hardwoods, including all species of oak, with white oak the preferred species.
Female moths deposit single eggs on leaves in May. Larval feeding occurs through August. Winter is spent in cocoons in the soil. There is one generation per year.
Although severe widespread defoliation can occur, outbreaks rarely last more than two years. Parasites and predators, especially birds, often control populations.
Forest Insect and Disease Leaflet 67 Variable Oak Leaf Caterpillar
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