The rapid advance westward of the European corn borer in 1926 has aroused the whole nation, particularly the corn belt states. New infestations were found all thru southern Michigan, across northern Ohio and into six counties in northeastern Indiana. An isolated infestation was discovered in Kankakee County, Illinois, only about 150 miles from Iowa.

A number of caterpillars occurring in Iowa are frequently mistaken for the Eropean corn borer. Some of these are of about the saine size and quite similar in color markings and general appear.ance, while others, even tho they are very different in appearance, cause injury which resembles somewhat the work of the European corn borer. This circular is issued . to acquaint farmers and Iowa people in general with the habits and characters of these caterpillars. By careful consideration of the larval descriptions, the time of appearance, and character of the injury, the European corn borer may be distinguished from most of the caterpillars discussed in this circular. The smartweed borer and the lotus borer are exceptions, because they so closely resemble the European corn borer that it requires an expert and a microscope to identify them with certainty.