REPOET OF THE SOCIET"i 51 



THE DISCOVERY OF THE EUROPEAN CORN BORER IN SOUTHERN 



ONTARIO 



Leonard S. McLaine, Chief, Division Foreign Pests Suppression, Entomological 



Branch, Ottawa. 



Ever since the European Corn Borer was realized to be a serious pest, that is 

 in the summer of 1918, the Dominion Department of Agriculture has taken 

 steps to warn the general public of the danger of introducing the pest into the 

 corn growing sections of Canada, as well as to find out if the pest had already 

 been introduced. 



It was with this latter object in view that scouting work for the European 

 Corn Borer was carried on in the Maritime provinces in the summer of 1919. 

 In the fall of the same year tliis insect was found in western New York bordering 

 the shores of Lake Erie. Through the co-operation of the United States officials 

 in charge of the work, two Dominion scouts proceeded to the New York out- 

 break to receive instruction in scouting for the pest. They later scouted in 

 Welland County, Ontario, but the work was soon discontinued on account 

 of the lateness of the season and the general weather conditions. Plans were 

 formed, however, for extensive scouting to be carried on in southern Ontario 

 during the summer of 1920, special attention being paid to the districts border- 

 ing on Lake Erie. 



Early in August two scouts equipped with motorcycles, started the scout- 

 ing work as the corn was coming into tassel. On August tenth Messrs. Keenan 

 and Simpson found some suspicious looking larvae in a field of ensilage corn, near 

 Lorraine Station, Humberstone Township, Welland County. The larvae 

 collected were very small and identification was difficult. These and later 

 collections were forwarded to Dr. J. M. ]McDunnough, Chief of the Division of 

 Systematic Entomology, for determination and were identified by him as being 

 larvae of the European Corn Borer {Pyrausta )iuhilah's Hubner). Plans were 

 then formulated to determine the area infested by the insect. 



On August 22nd a farmer in the vicinity of Aylmer, Ontario, submitted 

 samples of larvae to the Dominion Entomologist and these were also determined 

 by Dr. McDunnough as those of the European Corn Borer. A preliminary 

 examination of the fields in this locality indicated that the intensity of the infest- 

 ation was much greater than that in Welland County. 



The season was advancing rapidly and with apparently two distinct infest- 

 ations to deal with, it was necessary to take on additional men and furnish 

 better means of transportation. The Ontario Department of Agriculture co- 

 operated in this scouting work through the courtesy of Professor L. Caesar, 



