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when their wings are extended, and in general much resemble the 

 fall web-worm moth, which, however, has no brown tail. 



During July the moths lay their eggs in clusters mixed with the 

 brown hairs from the end of the body. The clusters are usually 

 placed on the underside of leaves and only rarely on the bark, and 

 each includes about three hundred eggs In August the eggs hatch 

 into tiny caterpillars, which feed on the leaves, keeping together in 

 colonies. They may feed on a large number of kinds of plants, but 

 appear to prefer the pear and other fruit trees, the oak, elm and 

 mountain ash, and when abundant may skeletonize the leaves of an 

 entire tree at this time. In September each colony passes to the 

 tip of some twig and here constructs a tent or nest in which to pass 

 the winter. This tent is of very closely woven silk threads, and is 

 rarely over four or five inches long by two or three inches at its 

 greatest diameter. It may easily be distinguished from the tents of 

 other insects by its toughness and firmness, its small size, by its loca- 

 tion at the very tips of the branches, and by the presence within it 

 during the winter of hundreds of caterpillars one-fourth to one-third 

 of an inch in length. After making the tent, the caterpillars may at 

 first leave it on warm days to continue feeding, but they soon retire 

 to it to pass the winter. 



In the spring the caterpillars desert their winter quarters and 

 scatter to feed, attacking buds, blossoms and leaves, and becoming 

 full grown by the middle or latter part of June. They then pupate, 

 usually in the hollows formed by drawing the edges of leaves toward 

 each other, though occasionally in other places, and from these pupae 

 the moths appear early in July. 



Though this insect is less universally destructive to vegetation 

 than the Gypsy Moth, the fact that the hairs of the caterpillar, and 

 to some extent of the moths also, are very brittle, and contain a 

 poison irritating to the human skin, makes them serious pests. The 

 most effective methods of control are to cut off and burn the winter 

 tents before the caterpillars scatter in the spring ; to spray infested 

 trees with arsenate of lead when the caterpillars begin their work in 

 August (except on trees bearing fruit), and also when the leaves de- 

 velop in spring ; to band uninfested trees not touching those which 

 are infested, with Tree Tanglefoot, though this will not prevent moths 

 from flying to such trees in July and laying their eggs there ; and to 

 . destroy the moths which have been attracted to lights. Relief from 



