During 1984 and 1985 macrolepidopterous larvae were collected by means of pole pruning from foliage of black birch, mixed oaks, black cherry, and red maple at Cooper's Rock State Forest in northern West Virginia. From 46 species of caterpillars, 74 species of parasitoids in eight families were reared. The most abundant parasitoids were Tachinidae (Diptera): Hyphantrophaga virilis (Aldrich and Webber) and Compsilura concinnata (Meigen); Braconidae (Hymenoptera): Protapanteles paleacritae (Riley), Microplitis hyphantriae (Ash.), and Diolcogaster facetosa (Weed); Eulophidae (Hymenoptera): Euplectrus maculiventris (Westwood), Eulophus anomocerus (Crawford), and E. nebulosus (Prov.); and Perilampidae (Hymenoptera): Perilampus canadenis (Crawford).