390 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



by Blephari'pa scutellata was very heavy in the northern part of 

 the infested territory, particularly at certain points in New Hamp- 

 shire, west of the Connecticut River. While this insect was re- 

 covered, it did not occur in as great abundance in the southern part 

 of the infested region. 



Parasitism of the small caterpillars that hibernate in the brown- 

 tail moth webs was slightly greater than last year, and the larvse this 

 spring were rather heavily parasitized by Gompsilura concinnata. 



The Calosoma bettle and its larva have been reported very 

 abundant, particularly in sections where gipsy moth and brown- 

 tail moth infestations have been heavy, and in such localities the 

 wilt disease has attacked the large larvae and pupae and caused 

 heavy mortality. 



Careful study of the biology and habits of the different enemies 

 has been undertaken and many new and important facts of scientific 

 importance have been discovered. Some of this information has 

 already been published in bulletins, but further work is required to 

 secure complete data on many phases of the parasite investigations. 



Data have been secured for a series of years to determine the 

 effect of defoliation on different species of trees growing under 

 varying conditions. The record of mortality of trees under ob- 

 servation has been made and the retardation of growth due to 

 periodic defoliation is being obtained. This information will be 

 extremely useful as soon as this investigation is complete. Experi- 

 ments of importance to all phases of the gipsy moth project and 

 some that have a broader application along the line of insect control 

 are under way. 



Tests designed to secure more effective methods of control work 

 in the field have been conducted. Aircraft of the heavier and 

 lighter than air types have been tested for dusting infested forests, 

 in cooperation with the United States Air Service, but this work 

 has not yet proceeded beyond the experimental stage. Some experi- 

 ments have been made with adhesive materials for the purpose of 

 preventing poisoned sprays from washing from the foliage during 

 wet weather. 



The application of the results of this experimental work is bound 

 to have a far-reaching effect on gipsy moth control in the future. 



Quarantine and inspection work. — The area infested with the 

 gipsy moth and the brown-tail moth has been placed under quaran- 

 tine by the Federal Horticultural Board. 



Products likely to carry these insects must be inspected before 

 they can proceed out of the infested area. State quarantines regu- 

 late the intrastate movement of such products. 



During the year 56,799 shipments have been inspected and certi- 

 fied. The number shows a marked increase over that of the previous 

 year. 



Scouting and extermination w^ork. — The scouting w^ork was 

 carried on during the past year under extreme difficulty. The sup- 

 ply of experienced men was very limited, and it was necessary to 

 train a large force for work in New England and New Jersey. The 

 volume of the work was curtailed in New England on account of 

 heavy snowfall in December, so that much of the scouting in Ver- 

 mont had to be discontinued earlier than usual. 



