REPORT OF THE SOCIETY 31 



the abundance of food plants of various species which extend throughout the 

 Valley. Owing to the different conditions it is necessary to modify the work in 

 the two provinces. In New Brunswick the infested area is only examined once, 

 whereas, in Nova Scotia it is often necessary to examine certain localities, where 

 the nests are plentiful, two or three times in order to clean them up. 



For a number of years the infestation was confined to the western end of the 

 Annapolis Valley, and it was hoped that it would be confined to this area by the 

 artificial barrier of Kings county to the east. This county has a large acreage in 

 orchard, most of these being well taken care of and thoroughly sprayed. Unfor- 

 tunately the pest passed this barrier and has extended as far east as Windsor. As 

 soon as this fact was established a counter attack was planned, and the present 

 policy is similar to that adopted by the United States Government in their 

 gipsy moth and brown-tail moth control work; that is, confining the pest to 

 its present area by laying particular stress on the outside territory of the infesta- 

 tion and gradually working towards the centre. 



Local infestations have caused a good deal of trouble in handling the control 

 work in Nova Scotia and in several instances radical measures have been necessary. 

 In 1915-16 two thousand nests were collected on a hillside atTorbrook. The 

 vegetation consisted largely of thorn and it was soon seen that hand picking of 

 the nests would not be effective. The entire area was sprayed with oil and burned 

 over. Excellent control resulted from this treatment and the area has been com- 

 paratively free ever since. The same year a small island in the Sissiboo river at 

 Weymouth Falls was found to be heavily infested. The vegetation consisted of 

 scrub thorn, rose, etc. and many of the nests were found close to the ground. The 

 island was accorded the same treatment as that at Torbrook, with the result that 

 the entire area was entirely freed of the brown-tail moth, no nests being found 

 during the past two years. 



Although there has been a gradual reduction in the number of nests collected 

 in Nova Scotia during the past few years, as is shown by the following table, we 

 realize that the brown-tail is breeding extensively ; furthermore the most con- 

 scientious inspector may miss nests, and in a mild winter the mortality rate among 

 the hibernating larvae will be low. Consequently it is necessary to continue a 

 vigourous campaign to keep this pest within bounds. 



Nests Collected in Nova Scotia 



