of forest and shade trees and ornamentals. The family has been 
treated by Engelhardt (2303) and MacKay (489). 
The hornet moth, Aegeria apiformis (Clerck), an introduced 
species first observed in North America around 1880, is now 
known to occur in Massachusetts, Connecticut, New York, New 
Jersey, Pennsylvania, and California. Its hosts are poplar and 
willow. The larvae bore in the roots, trunks, or large limbs. The 
adult is brownish-black except for yellow markings on the head 
and sides of the thorax; it has a wingspread of 34 to 44 mm. It 
also has black and yellow bands on the abdomen and brown legs. 
Because of its close resemblance to the giant hornet, it is known 
as the hornet moth. Full-grown larvae are white with reddish 
heads and are about 30 to 50 mm. long. They excavate extensive 
tunnels in their hosts, causing swellings to occur. Young trees are 
often killed. Two years are required to complete the life cycle. 
The first winter is spent in the larval stage in the wood; the 
second, as a larva in a cocoon in wood borings in or close to the 
base or roots. 
Aegeria tibialis (Harr.) attacks poplar and willow from New 
York to Nova Scotia and in the Midwestern States. Adults are 
distinguished by their black abdominal segments, all but the 
second and fourth of which have narrow posterior yellow margins. 
Full-grown larvae are 40 mm. or more long. Infestations are lo- 
cated well down on the trunk or in the roots. 
The dogwood borer, Synanthedon (=Thamnosphecia)  scitula 
(Harris), occurs in southeastern Canada and throughout the 
eastern half of the United States. Although normally a bark 
borer in oaks, it also attacks a wide variety of other deciduous 
hardwood trees, and shrubs, and sometimes pine. It is often an 
important pest of flowering dogwood and pecan. In the South, it 
is commonly called the pecan borer. Abnormal growths such as 
woody galls, excrescences due to fungi, rusts, blight, and bruises 
and healing wounds are attractive as points of attack. Galls, such 
as those produced by the cynipid Andricus cornigerus on black 
and pin oaks, sometimes occur in the thousands on a single tree, 
and nearly every one will be infested by this borer (230). 
The adult is a small, blue-black moth with yellow banded legs 
and yellow stripes on segments two and four of the abdomen. The 
wings are transparent with blue-black margins, and the wing 
spread is from 14 to 20 mm. The larvae are whitish with brown 
heads and are up to 14 mm. long. 
Eggs are laid from late spring to mid-summer on rough bark 
or around wounds. The larvae enter the bark through openings 
and feed in the cambial area. Infested areas are sometimes up to 
2 feet or more in length and may contain up to 50 larvae each on 
the larger trees. A single larva can kill a dogwood 4 inches in 
diameter in one year. There are one and possibly two generations 
per year, depending on locality. Keeping the bark smooth, es- 
pecially at the base of branches has been recommended for control 
on dogwood (737). 
The rhododendron borer, Synanthedon (=Ramosia) rhodo- 
dendri Beutenmuller, attacks rhododendron and sometimes laurel 
and azalea in the Atlantic Coastal States. The adult is blackish, 
except for various white and yellow markings, and has a wing- 
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