4 Farmers’ Bulletin 1294. 
Recent advices from the Canadian authorities report the European 
corn borer as present in an area of about 7,690 square miles, com- 
prising most of the southern Ontario peninsula bordering Lake Erie 
and including Pelee Island. The infested area extends on the north 
to Goderich on Lake Huron, and on the east to Lake Ontario and the 
Niagara River. There is also a small isolated infestation on the 
northern shore of Lake Ontario. 
PROBABLE METHOD OF INTRODUCTION. 
The exact date and manner in which this European pest gained 
entrance to the United States is not definitely known, but circum- 
stantial evidence accumulated since its discovery indicates strongly 
that broom corn imported from Hungary and Italy in 1909 and 1910 
was the carrier. Broom factories which received this foreign ma- 
terial were located near the centers of infestation at Everett, Mass., 
and Amsterdam, N. Y. An apparent confirmation of this probable 
method of introduction was afforded when two shipments of broom 
corn, received at the port of New York from northern Italy during 
February and March, 1920, were found to be infested and shipments 
received from Hungary during April, 1922, were found to be simi- 
larly infested. Broom corn is commonly infested by this insect in 
Europe. 
Raw hemp formerly was believed to be the most likely medium 
through which the insect gained entrance to this country, but this 
theory has been abandoned. 
From present indications it is believed that the infestations on the 
islands and along the shore of Lake Erie in Michigan, Ohio, and 
Pennsylvania may have originated from the badly infested area just 
across Lake Erie, in the Province of Ontario. The history and in- 
tensity of this Canadian infestation indicate that it is probably the 
oldest colony of the pest in this region. The infestation in western 
New York may also have originated from the same source, although 
the origin of this infestation is more obscure. The method of dis- 
persion from Ontario may have been by forced flight of the moths or 
by the drift of infested plant material in the waters of Lake Erie; 
at the present writing, however, no traces of such material have been 
discovered. A study of the wind and water currents in the Lake 
Erie section, in conjunction with the known habits of the insect, 
shows the possibility of such dispersion through either of these 
agencies. Recent experiments have shown the moth to be capable of 
a flight of nearly 20 miles. 
PLANTS ATTACKED BY THE INSECT IN THIS COUNTRY. 
Corn is injured by the larve, or borers, of the European corn borer 
to a greater extent than any other cultivated crop attacked by the in- 
sect in this country. The borer attacks sweet corn, field corn (both 
dent and flint), pop corn, and corn planted for fodder or silage. 
Corn doubtless is the preferred host of the insect in North America, 
as it is in Europe. In the badly infested area in New England 
the borers also attack a variety of other plants, including field crops, 
vegetables, flowers, grasses, and weeds. (Fig. 1.) 
