Females are larger than males. Neither sex has scattered small black specks. Females lay eggs in the early evening in clusters on oak leaves.
Young caterpillars feed together, but become solitary as they grow.
Fully-grown caterpillars pupate and overwinter in shallow underground chambers. One brood from July-August. G4 - Apparently secure globally, though it might be quite rare in parts of its range, especially at the periphery. The moths of America north of Mexico, fasc. E. W. Classey Limited and R. B. D. Publications Inc., Middlesex, England.