shining white markings on the forewings and the wingspread is about 21 mm. 
Larvae feed from April to July, dropping to the ground for pupation and overwinter- 
ing. There is one generation per year. E. tocullionana Heinrich, the white pine 
cone borer, has been recorded from Ontario and New Brunswick, Canada, and 
from Wisconsin, Massachusetts, New York, Connecticut, Pennsylvania, Virginia, 
North Carolina, and Tennessee. The larvae feed on the cones of various conifers, 
such as eastern white pine, spruce, balsam fir, and eastern hemlock (996). 
The cottonwood twig borer, Gypsonoma haimbachiana (Kearfott), has been 
recorded from Ontario, from the northern tier of States from New York to Michigan 
and south through the Midwestern States of Missouri, Oklahoma, Arkansas to 
Mississippi, Louisiana, and Texas. Its hosts are listed as various poplars. The adult 
is ash gray and has a wingspread of about 15 mm. The basal portion of the forewing 
is darker than the apical portion. Full-grown larvae are pale and about 15 mm long. 
The head is brownish yellow; the thoracic shield, brownish yellow edged with 
brown; and the anal shield, brown or grayish. 
Winter is spent mostly as young larvae in silk-covered, shallow pits excavated in 
healed-over borer entrance holes, in the margins of corky bark ridges below leaf 
bases, or in depressions of leaf scars. Lesser numbers of late instars overwinter in 
hollowed-out terminal buds. When the younger larvae resume activity in the spring, 
they enter the tender, new shoots to feed and complete their development. When the 
older overwintering larvae resume feeding in the spring, they frequently kill the bud 
and up to 25 cm of the terminal. There appear to be four or five generations per year 
in the Mississippi Delta Region (877). 
This is one of the most destructive of the insects that damage young eastern 
cottonwood trees. Damaged trees are stunted, have crooked trunks, and produce too 
many limbs. This leads to a great reduction in the quality and quantity of merchant- 
able pulpwood, saw logs, or veneer from these trees. 
Proteoteras moffatiana Fernald feeds on terminal buds of maples. The resulting 
disruption in apical dominance causes forking and branching which seriously 
affects tree quality of sugar maple in the Lake States (S557). This insect occurs in the 
Northern United States and southern Canada from the Atlantic Coast to Wisconsin. 
The adult is bright green with irregular, brown forewing markings and has a 
wingspread of about 17 mm. There is one generation per year and adults are present 
in July and August. In late summer, larvae enter and mine terminal buds in which 
they pass the winter. In spring they mine additional buds before shoot elongation is 
completed. 
Proteoteras aesculana Riley occurs throughout southern Canada and the North- 
ern States, south to Tennessee. The adult is olive green with yellow, gray, and black 
markings, and has a wingspread of about 14 mm. The larvae bore in the seeds, leaf 
stalks, and terminal twigs of buckeye and maple and sometimes cause serious 
injury. Seedlings in nurseries have been heavily attacked. Adults emerge in July and 
August. 
The boxelder twig borer, P. willingana (Kearfott), attacks boxelder and maple 
in many of the Northern and Midwestern States and southern Canada. The adult is 
white to brownish, marked with streaks, rings, and clusters of yellowish-tan to 
black scales; it has a wingspread of about 17 mm. The larva destroys dormant leaf 
buds in the fall and early spring. Later in the spring, it burrows in succulent twigs 
(fig. 55), causing the formation of spindle-shaped galls (982). These galls become 
woody when they dry out. This usually prevents further terminal growth. Severe 
damage has been recorded in shelterbelt plantings in the Prairie Provinces of 
Canada. 
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