Family Noctuidae 
Owlet Moths and Underwings 
This is the largest of all the families of Lepidoptera in North America. There are 
more than 2,900 species in the Noctuidae in North America. The adults are mostly 
nocturnal; many of the moths attracted to lights at night belong to this group. The 
larvae are usually dull colored and naked. Many are foliage feeders, some are 
borers, and others gnaw in fruits. Others are found on the foliage of forest and 
shade trees and shrubs, but they usually do not cause serious damage. A number of 
species attack seedlings in nurseries and young trees in plantations, and occasion- 
ally cause serious injury. This family has received extensive treatment (268, 435, 
684, 1002, 1032, 1108). 
The genus Acronicta contains upwards of 100 species, many of which feed on the 
foliage of forest and shade trees. Some are known as “‘dagger moths” because of the 
presence of a daggerlike mark near the anal angle of the forewing. 
The American dagger moth, A. americana (Harris), occurs throughout the 
Eastern United States and from Newfoundland to Alberta, Canada. Its hosts include 
a wide variety of hardwoods such as boxelder, basswood, red and sugar maples, 
paper and yellow birches, elm, ash, oak, willow, hickory, and sycamore. Full- 
grown larvae are about 50 mm long. They are clothed with fine, yellowish hairs and 
there are long, black hair pencils on the backs of abdominal segments one, three, 
and eight. Larvae are present from June to October, and overwinter in the pupal 
stage in dense silken cocoons. During an outbreak in Maine, larvae were so 
abundant that they literally swarmed all over buildings and gardens. 
The cottonwood dagger moth, A. lepusculina Guenée, occurs from coast to 
coast in southern Canada and the Northern States. Its favorite hosts appear to be | 
willow and quaking aspen, but it also occasionally infests other species of poplar. 
Full-grown larvae are clothed with long, soft, yellowish hairs and are about 37 mm 
long. There are single, long, black hair pencils on the backs of abdominal segments 
one, three, four, five, and eight. Larvae are present from July to October. Winter is 
spent in a cocoon composed of silk and bits of wood. 
Many other species of Acronicta are also found on trees in eastern forests. Some 
of these with some of their more common tree hosts are as follows: A. innotata 
Guenée—hickory and birch; A. morula Grote & Robinson, the elm dagger 
moth—elm and basswood; A. interrupta Guenée—elm, cherry, birch, and apple; 
A. lithospila Grote—hickory and oak; A. funeralis Grote & Robinson, the paddle 
caterpillar—hickory, elm, and birch; A. modica Walker—oak; A. retardata 
(Walker)—maple; A. leporina (L.), the poplar dagger moth—poplar, willow, and 
birch; A. distans (Grote)—birch, cherry, poplar, willow, apple, and alder; and the 
smeared dagger moth, A. oblinita (J. E. Smith)—usually herbaceous vegetation 
but also occasionally poplar, willow, boxelder, pin cherry, alder, and apple. 
The genus Catocala contains many large, conspicuous species, the larvae of 
which feed on the foliage of various forest trees and shrubs. As a group, they are of 
little economic importance. The forewings are usually grayish and mottled with 
lighter and darker spots. This makes them very inconspicuous on the trunks of trees 
when they are resting with their wings folded. The hindwings, in contrast, are 
beautifully marked with bright red, yellow, white, or brown. This has given rise to 
the common name “underwing moths.” More than 50 species have been recorded 
from New York State alone, mostly on oak and hickory. The life histories of many 
species have been discussed (56, 1/055). 
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