Heavenly heartland

Ah, Iowa. The rustle of cornstalks, chirping of crickets, and distant roar of jet engines is all you're likely to hear this deep in the heartland. Checkered from border to border with rolling cornfields like this, the Hawkeye State leads the country in corn growing, regularly producing more than two billion bushels in a year.But only a tiny portion of that corn will be munched off a cob or scooped from a can. Sweet corn barely makes up a percentage point of the US corn crop (and sorry, snack lovers, but the poppable cultivar is even less common). The vast bulk of the harvest is field corn, destined to become ethanol fuel or livestock feed.