U.S. Department of Agriculture (USDA) scientists in Peoria, Ill., are investigating the pest-fighting potential of anthocyanins, healthful chemical compounds in the form of plant pigments that give blueberries, plums, grapes and flowers such as petunias their blue and purple color.

Like the swallows that return to Capistrano, it seems that purpling in young corn returns every year somewhere, says Bob Nielsen, Purdue University corn agronomist.