An employee using the egg punching machine

Twenty-day, egg-laying triangle for the central Corn Belt during the second moth flight indication the best time to sample egg masses on field corn (D. D. Calivin).

Egg-laying period of European corn borer in the central Corn Belt during the second moth flight represented by a 20-day triangle. Shaded area is proportion of total eggs laid if a sample was taken 8 days after the first eggs were deposited (D. D. Calvin).

European corn borer egg mass with numerous eggs on underside of corn leaf (M. E. Rice).

Newly-laid eggs of the European corn borer are milky-white in color. The eggs overlap each other like fish scales.

Newly-laid eggs of the European corn borer are milky-white in color. The eggs overlap each other like fish scales and are often laid near the leaf midrib.

Egg sacs of spiders on corn leaves may be confused with European corn borer eggs because of their similarity in color and size. However, spider egg sacs are usually fuzzy and not overlapping like fish scales.

European corn borer eggs are usually laid on the underside of a corn leaf. This egg cluster contains 38 eggs.

European corn borer eggs are usually laid on the underside of a corn leaf. Often the eggs are found near the leaf midrib.

These eggs have reached the blackhead stage and the larvae will hatch shortly. This egg mass contains 22 eggs.