SHADE TREE INSECTS 23 



The mature caterpillar is about IV^ inches long with four dense, white, brush- 

 like tufts of hair on its back. Behind these are two shiny red wartlike growths. 

 The head is brilliant coral red. There are two long pencils of black hair, about 

 ]/2. inch long, which extend forward, arising just back of the head, one on each 

 side. A single pencil of hair extends backward from the rear of the body. A 

 broad black band extends almost the entire length of the back and is bordered by 

 a yellow band on each side. The yellow bands are bordered with dark gray. 

 Through the spiracles along the side there extends a thin black stripe. On the 

 sides of the body are clusters of white bristles, with a brilliant black bristle oc- 

 casionally intermingled. 



When ready to pupate, the mature caterpillar spins a thin cocoon into which 

 are woven the long hairs from its body. Sometimes the cocoons occur in great 

 masses. Inside the cocoon the caterpillar transforms to a yellowish-white pupa 

 which is more or less shaded with dark brown or black. The male cocoons average 

 about 9/16 inch in length; the female, about 11/16 inch. 



Life History. The insect passes the winter in the egg stage. The eggs hatch 

 in early May and the tinj' caterpillars feed on the green tissues of the lower leaf 

 surface, skeletonizing the leaves. When disturbed the caterpillars drop, sus- 

 pending themselves on silken threads, and may then be blown by the wind some- 

 times for a considerable distance. When nearly full grown, the caterpillars crawl 

 about, often migrating to other trees. In about 5 weeks they mature and spin 

 their cocoons on the bark of the trunks, branches, and even twigs, among leaves, 

 or sometimes in protected places on near-by buildings and fences. The moths 

 emerge in about 2 weeks. After mating, the females deposit their eggs for the 

 next generation. In the vicinity of Albany there is normally one generation 

 annually; in the vicinity of Boston and New York City and in Connecticut there 

 are two generations a year. 



Control. Spraying the foliage thoroughly, especially the under side of the 

 leaves, when the caterpillars of the first generation are still very small in the 

 spring, is the preferred method of control. About 4 pounds of lead arsenate to 

 100 gallons of water should be used, with 2 pounds of flour or 1 pound of calcium 

 caseinate added as a sticker. 



Egg masses may be collected and burned or they may be painted with creosote 

 as are those of the gypsy moth. Many of the egg masses of this insect, however, 

 are laid near the tops of the trees and in other inaccessible places. If the infested 

 trees are small and other conditions are such that most of the egg masses can be 

 reached and destro^'ed, this method gives good protection. The degree of in- 

 festation should also be considered. Hand-picking operations are too expensive 

 for use in severe outbreaks. 



Isolated trees which are free from attack may have the trunks banded with 

 tanglefoot or other sticky substance to prevent mature, migrating caterpillars 

 and wingless female moths from climbing up into them. 



The parasitic insects, diseases, and insectivorous birds which prey upon this 

 insect are instrumental in holding it in check except for occasional outbreaks. 



Balch, R. E. Jour. Econ. Ent. 25:1143-1148. 1932. 



Britton, W. E. Conn. State Ent. Rpt. 16:105-111. 1917. 



Britton, W. E., and Friend, R. B. Conn. Agr. Exp. Sta. Bui. 369:274-276. 1935. 



Felt, E. P. N. Y. State Mus. Bui. 156:14-17. 1912. 



Felt, E. P. N. Y. State Mus. Mem. 8(1) :132-142. 1905. 



Fernald, C. H. Hatch Exp. Sta. Mass. Agr. Col. Bui. 20:13-16. 1893. 



Houser, J. S. Ohio .\gr. Exp. Sta. Bui. 332:207-213. 1918. 



Lintner, J. A. N. Y. State Mus. Rpt. 49:124-126. 1896. 



McDaniel, E. I. Mich. Agr. Exp. Sta. Spec. Bui. 243:15-17. 1933. 



