its preferred hosts, but many other species of deciduous trees are fed upon in 
heavily infested stands. The adult is greenish gray or brownish gray with splotches 
of creamy white, and has a wingspread of about 50 mm. Full-grown larvae are 
usually gréen with reddish to purple or brown markings on the back, and they are 
about 30 mm long (fig. 95). 
Adults emerge in late May or early July and the female deposits from 200 to 300 
eggs singly on the lower surfaces of the leaves. Young larvae skeletonize the upper 
surface of leaves; older ones eat the entire leaf except the principal veins. They 
often migrate from tree to tree and, where abundant, may collect in large numbers 
about the bases of defoliated trees. Pupation occurs in the leaf mold from mid-July 
until late August. Winter is spent in the pupal stage. There is one generation per 
year in the northern parts of the insect’s range. 
Many outbreaks have been recorded since the turn of the century (222, 96/) 
during which heavy defoliation occurred over large forested areas. In areas suffer- 
ing two consecutive years of defoliation, considerable tree mortality occurred. 
Many of the trees that survived lost some of their large branches as well as large 
portions of their tops. The most damaging effects of defoliation of sugar maple 
occur to sapling and pole-size trees on poor sites (504, 707). 
Figure 94.—The variable oakleaf caterpillar, 
Heterocampa manteo: A, adults; B, larvae. 
F-519533 
Figure 95.—Dorsal and lateral views of larvae of the 
saddled prominent, Heterocampa guttivitta. 
22\ 
