ENTOMOLOGICAL SOCIETY OF ONTARIO. 



cleared and rubbish burned. By the time the eggs hatched the greater part of the bur- 

 laps had been placed on the trees. Spraying with arsenate of lead was commenced as 

 soon as the leaves developed and was continued until about the middle of June. The 

 poison mixture was applied at the rate of 20-150 gal. water, and about three tons of 

 ingredients for making arsenate of lead were used in this work. The season proved a 

 very unfortunate one for spraying operations. In May there were, I think, twenty 

 days on which rain fell, and in June sixteen. In many cases this nullified the effect of 

 the poison to a great extent and necessitated respraying. But even under these condi- 

 tions from 60 per cent, to 80 per cent, of the larvae in infested sprayed woodlands 

 were destroyed. 



Spraying with the arsenate of lead has this year shown itself as one of the best 

 and cheapest methods for controlling the increase of the Gyp3y moth. The extremely 

 wet season favored a rank growth of foliage ; this gave the insects abundance of shade^ 

 and later a great part of the large caterpillars refused to come to the burlaps, but 

 remained clustered in tree tops. This necessitated the expensive operation of climbing: 

 a large number of trees. The season seemed also very favorable to the growth of cater- 

 pillars aside from food considerations. The abundance of tent caterpillars and canker 

 worms, as well as the Gypsy moth, during the past summer confirmed this view. 

 Thorough attention to the burlaps, however, as the caterpillars matured, together with 

 the climbing of trees and destruction of large numbers by hand, made a great inroad 

 into the ranks of the insect. Active operations were not relaxed until all the nests had 

 been laid, and large numbers of pupae and few moths were destroyed by hand, thus 

 preventing the deposition of a great many egg-clusters. In the summer work from 200 

 to 366 men were employed. By the time the moth ceased laying our funds ran shorty 

 125 men were discharged and the wages of others reduced.. Later, to diminish expenses 

 still further, the entire force was laid off for two weeks. At present writing, a care- 

 ful search is being made of some outlying districts, while in the inner towns a force of 

 men is at work treating nests. As soon as the leaves have fallen the work in the out- 

 lying towns will be prosecuted, so far as means permit. 



Results, of the Tear's Work. 



The results of the year's work may be summarized briefly as follows : The increase 

 and spread of the Gypsy moth has been well controlled, and there has been less strip- 

 ping of trees throughout the whole infested region than ever before. In the outer towns 

 marked progress has been made towards extermination. The number of outlying 

 colonies has never been so small as at present, and the infestations of the territory 

 included within the border of the infested region were never so well known. The num- 

 ber of insects taken this year in the existing outlying colonies is much smaller than 

 that of 1896. For example, in one of the Brookline colonies about 15,000 larvse were 

 destroyed in 1896, where but 191 were found in the same place the past summer, 

 While much good work has been accomplished in the outer towns, it is apparent that the 

 moth has increased near the centre of the infested district. The results of a hasty 

 inspection indicate that the numbers of the moth have increased in Maiden and vicinity, 



Considerable areas of woodland in the large Metropolitan Park system are known 

 to be infested, but their condition, on the whole, is better than that of last year. The 

 destruction of the eggs previously mentioned prevented the increase of the insect in the- 

 woodlands. Owing to the amount of travel through the parks this infestation will 

 menace the surrounding region, until funds permit the prosecution of exterminative 

 work in the parks. 



What is Needed. 



So far we have been unable to burn the candle at both ends. With insufficient 

 means we cannot carry on exterminative work over the whole region. Either the out- 

 side or inside territory must be neglected to a certain extent. To restrict the border- 

 line of infestation has seemed to be a matter of vital importance to the success of the 



