The caterpillars are approx. 25-30 mm long, yellowish or reddish-brown in color, and have a dark dorsal line as well as a dark head capsule. The body has numerous black warts (Picture 1). The moths are approx. 12-15 mm long and yellowish-brown in color (Picture 2). The forewings have a span of up to approx. 30 mm and are marked with jagged transverse bands as well as spots.
European corn borer [Ostrinia nubilalis]
Chiefly in maize, but also in other plant species such as potatoes and barnyard grass.
Pattern of damage
Stalks, tassels, or cobs are broken or bent over. Small boreholes surrounded by light-colored frass can be found below the breakage sites (Picture 3). The destructive caterpillars not only mine in the interior of the plants, but also leave distinct signs of feeding damage on cobs and kernels.