GYPSY AND BROWN-TAIL MOTHS AND THEIR CONTROL 29 



sprayed. A larger area was thinned and cleaned during the fall and 

 winter. 



The work has been intensified and expanded since that time, and 

 there has been a marked decrease in the number of egg clusters treated 

 each year. Some new infested points have been found, and they have 

 been promptly treated. No defoliation has been noted since the 

 first summer. The infested areas and some of the surrounding town- 

 ships have been placed under a State quarantine, and movement of 

 materials likely to carry the insect is not permitted until they have 

 been inspected and certified by officials from the Wilkes-Barre office. 



The area infested in 1935 is shown in figure 15. The present 

 infested area aggregates 680 square miles, and additional areas sur- 

 rounding it totaling 320 square miles are covered by the quarantine 

 and inspection regulations. This includes Coolbaugh and Foster, 

 which were added in 1936. 



Substantial progress has been made on this project in Pennsylvania, 

 and excellent cooperation has been received from the State. The 

 territory is located in the heart of the anthracite district, and much 

 of the country is wooded and mountainous, and therefore difficult 

 to work. Part of this area is in the valley of the Susquehanna and 

 Lackawanna Rivers, and some infestations have been found in the 

 Pocono Mountain range. This infestation is located the farthest 

 west of any in the United States, and the importance of reducing the 

 abundance of the insect and bringing about its final extermination can- 

 not be overestimated. If the work is not continued aggressively, 

 the insect might spread rapidly to surrounding territory and to other 

 States where it is not now known to exist. 



THE BROWN-TAIL MOTH 

 HISTORY OF THE PEST IN THE UNITED STATES 



The brown-tail moth (Nygmia phaeorrhoea Don.) was first found in 

 the United States in Somerville, Mass., in the summer of 1897, and 

 was undoubtedly introduced several seasons previous to that time on 

 imported nursery stock. The insect increased enormously, and as the 

 caterpillars were fond of the foliage of fruit and ornamental trees and 

 shrubs, they became an unbearable nuisance, particularly in residential 

 sections. Not only was complete defoliation common early in the 

 summer, but as the hairs from the caterpillars caused serious poisoning 

 to human beings the presence of this pest became a veritable scourge 

 in densely populated areas. The insect extended its range very 

 rapidly, because the moths of both sexes fly freely. This species 

 occurs in many parts of Europe and is frequently very injurious. 



The State of Massachusetts applied suppressive measures from the 

 winter of 1897 until February 1900, when it discontinued the work 

 along with that of the gypsy moth. By 1905 the brown-tail moth was 

 extremely abundant in eastern Massachusetts. It was also present 

 in enormous numbers in Rhode Island, southern New Hampshire, 

 and southwestern Maine. Not only did fruit and shade trees suffer 

 defoliation, but large areas of oak woodland, particularly sprout 

 growth, were completely defoliated. 



