10 FARMERS' BULLETIN 845 



THE BROWN-TAIL MOTH. 



SEASONAL HISTORY. 



' (Fig. 4.) 



As is the case with, all other moths, the brown-tail moth in its 

 development is first an egg, then a larva or caterpillar, then a pupa, 

 and finally an adult moth. 



The eggs. The female brown-tail moth deposits a small cluster of 

 eggs on the underside of a leaf. These eggs usually are laid in July 

 and are covered with brown hairs taken from the body of the female. 

 Hatching begins about the 15th of August. 



The larvse. The newly hatched larvae of this insect feed on the 

 epidermis of the leaf and after molting once or twice begin to con- 

 struct a winter web. This is made by drawing together several termi- 

 nal leaves and securely fastening them by silk which is secreted by 

 the caterpillars. The larvse from one or more egg clusters live and 

 feed in common, and as cold weather approaches they retire to the 

 web, in which they remain during the winter. In the spring these 

 larvse leave the web as soon as the buds begin to develop and feed 

 upon the bud scales and small leaflets. They become full-grown 

 about the middle of June. 



The pupsd. After the caterpillars finish feeding they spin loose 

 silken cocoons and pupate within them. These cocoons sometimes 

 are constructed separately, but in many cases large numbers of 

 them are spun in a single mass. About two weeks are spent in the 

 pupa state. 



The adults. Emergence of the moth usually begins the first week 

 in July. The adult brown-tail moth is pure white. The abdo- 

 men of the female is much larger than that of the male, but in 

 both sexes the tip of the abdomen is covered with dark-brown hairs. 

 These moths are attracted to strong light, such as electric arc lights, 

 and as they fly at night it is often possible to secure'many specimens 

 around the arc lights in cities and towns during the first half of the 

 month of July. 



POOD PLANTS. 



The caterpillars of the brown-tail moth commonly feed on apple, 

 pear, plum, oak, and willow, and sometimes they are found in con- 

 siderable numbers on elm, maple, and rose and in smaller numbers 

 on other common deciduous trees and shrubs. They never attack 

 conifers and are seldom found on hickory, ash, chestnut, or birch. 



INJURY CAUSED BY 1HE BROWN-TAIL MOTH. 



The principal injury caused by the brown-tail moth is due to the 

 feeding habits of the larvse in the spring. If the infestation is bad, 

 the caterpillars often are numerous enough to devour the leaves as 



