Small, shiny black, stout-bodied beetle with black legs adapted for jumping, ~1/16" long.

Feeds on leaves; causes narrow white strips by scraping off the green tissue between veins. May transmit Stewart's wilt.

May and into June (primarily eastern and southern Nebraska)

Count flea beetles on 25 corn plants in each of several locations in the field. Rate leaf damage according to scraping damage.

Four to five flea beetles per plant and corn < 6" tall, or leaves of seedlings with 30% of the green tissue removed and corn < 3-leaf stage.

http://www.unl.edu/entomology/extension/crops/fieldcorn.shtml