specific Pests i6i 



attached to crevices in the bark or other similar shelter, 

 and in the ground if soft enough, wintering in this condi- 

 tion. The small, pure white or brown and black-dotted 

 moths issue in June or July (the first southern brood in 

 May), and lay their bright golden eggs in large clusters on 

 leaves, usually on the under side and near the end of the 

 branches, from which the caterpillars issue within a week 

 or ten days. 



Besides the damage to the foliage, the disagreeable habit 

 of the worms of dropping from the trees is obnoxious in 

 city streets. Poplars, willows, box-elder, ash, cherry, elm, 

 and basswood suffer most from this pest, but nearly all other 

 trees are attacked if the food su]:)ply is scarce in a year of 

 excessive development. 



The easiest method of combating the pest is to cut off and 

 burn the webs, or burn them on the tree with a torch, with 

 proper caution to a\oid injuring the tree. Spraying with 

 arsenical poisons when the }oung caterpillars appear is 

 also effective. 



Bag Worm. The bags, one to two inches in length, in 

 which the caterpillars enclose themselves while feeding and 

 in which they finally pupate, are the readiest sign of their 

 presence. These bags are made of pine needles, bits of 

 foliage and bark, and are gradually built up by each indi- 

 vidual around itself. The caterpillars appear in May and 

 early June, and at once begin the construction of their 

 bags, lirst carrying them upright on their posterior body, 

 then, as they grow heavier, hanging down. In spite of 

 this impediment, they spin down and wander freely; finally, 

 in September, attaching themselves hanging down from 

 twigs, they pupate within the bag. The inconspicuous 

 males, with black hairy body and glassy wings, f]y in Sep- 

 tember and October; the females are wingless, hairless, and 



