The saddled prominent, Heterocampa guttivitta (Wlkr.), occurs 
in southeastern Canada and throughout eastern United States. 
Beech, paper birch, and sugar maple are its preferred hosts, but 
practically all other species of deciduous trees are fed upon in 
heavily infested stands, particularly the oaks and poplar. 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 green with purple, gold, and brown markings on the 
back, and they are about 30 mm. long (fig. 120). 
Adults emerge in late May or early June and the female de- 
posits up to 500 eggs singly on the leaves. Young larvae skeleton- 
ize 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 leafmold 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 cen- 
tury (148, 582), during which heavy defoliation occurred over 
large forested areas. In areas suffering 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. 
Other species of Heterocampa likely to be encountered in eas- 
tern forests include: H. umbrata Wlkr.—oak and maple; H. biwn- 
data Wlkr.—beech, paper birch, wild black cherry, and maple; 
and H. bilineata (Pack.)—elm and birch. 
Fentonia marthesia (Cram.) occurs from Maine to Florida and 
Texas and feeds on the leaves of beech, maple, aspen, oak, and 
sycamore. Full-grown larvae are pale green and up to 50 mm. 
long. The head is flat in front, there is a small, double reddish 
tubercle on the prothorax, and the body is marked with a longi- 
tudinal, yellowish white stripe and occasional pink spots on the 
back. Larvae feed from July to October then spin cocoons between 
leaves on the ground in which to pupate and spend the winter. 
Dicentria lignicolor (Wlkr.) feeds on various species of oaks 
and beech throughout eastern United States. The larva is about 
37 mm. long and resembles larvae of the genus Schizura. Its 
prominent characters include a pale, bilobed head, with dark 
branched bands on each side of the face meeting on the vertex. 
There is also a large, slightly cleft tubercle on the first abdominal 
segment and a smaller brownish one on the eighth abdominal 
segment. The sides of the thorax are pea green. Adults appear in 
July and August in the Northeastern States; the larvae, from 
August to October. Winter is spent in a tough, parchment-like 
cocoon on the ground. 
The red-humped caterpillar, Schizura concinna (J. E. Smith), 
occurs throughout the United States and in most of the Canadian 
Provinces. Its hosts include fruit trees and a long list of forest 
and shade trees, such as elm, trembling aspen, willow, hickory, 
black locust, dogwood, sweetgum, persimmon, and paper birch. 
The adult is grayish brown and has a wingspread of about 30 
mm. Full-grown larvae are about 25 mm. long. The head and a 
hump on the eighth abdominal segment are red; the body is 
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