to leaves or twigs from which they hang head down. Some, such 
as those of the families Papilionidae and Pieridae, are girdlers 
and do not hang head down. Skippers pupate in cocoons made of 
leaves fastened together with silk. 
The order Lepidoptera contains several destructive forest and 
shade tree insects. Several species such as the spruce budworm, the 
forest tent caterpillar, and the gypsy moth often occur in out- 
breaks covering tens of thousands of acres of woodlands, and 
losses are very great. Large volumes of timber may be killed, and 
larger volumes are lost through reduced growth of surviving 
trees. Many other species cause serious losses by boring into and 
destroying the buds and shoots of seedlings and young trees in 
forest nurseries and plantations, or by mining the tissues be- 
tween the upper and lower surfaces of leaves. The attractiveness 
of shade trees, parks, and other recreational areas is often re- 
duced or destroyed by these insects, fire danger is increased, and 
wildlife habitats are impaired. 
For a more extensive treatment of the order Lepidoptera the 
reader is referred to the following publications: Borror and De- 
Long (90), Dyar (213), Edwards (222), Forbes (258), Fracker 
(262), Holland (364, 365), Klotz (422), McGugan (482), Pren- 
tice (607, 608, 609), McDunnough (478), and Freeman (267). 
Field Key to Some Common Lepidopterous Larvae Attacking 
Eastern Forest and Shade Trees 
LES PADD) Ste Vea OT Spe erect roe) er UNE OR RE RIEL SAVE TNL al ccccasvs 2 
BOG CIS eae Be eek ae not a Rk Be ie ed EE IA ce. 15 
2. Miners. ‘casebearers; bag worms 22 e i ee e. 3 
Skeletonizers (leaves not webbed together) 00.0.0... 9 
leeatrollerscandeleat tiers: =e A Re eccanee 10 
Wielbworme cinodctent makers (ie ae da: 
Hueco CCUei Sars aos Became ere EN EE ede a Se 12 
3S Non=caseneatine leat MINers 266k 4 
Casebearing leaf miners, other casebearers, webworms ..... i 
At. Inthe rollage ot deciduous plants 2.72 ee. 5 
Iinethesneedleswor Pinacede a. 25... JL Pe aan. 6 
5. (1) Oak— 
a. Very small, flat, and reddish brown or black. 
SOMtAGye Lithocolletis hamadryadella. 
b. Very small, flat, and reddish brown or black. 
Gregarious. oe... Lithocolletis cincinnatiella. 
(2) Tupelo—Head and cervical shield dark-brown; body 
pale green and about 8 mm. long 
Antispila nyssaefoliella. 
6. (1) Arborvitae— 
a. Head, cervical shield, and anal plate blackish; 
body, reddish 3... Coleotechnites thuraella. 
b. Head brown; body yellowish-white with shield- 
shaped areas behind the head 
Argyresthia thuiella. 
ce. Head greenish or brownish; body yellowish-green 
to green (also on red cedar) 
Argyresthia freyella. 
275 
