They cultivated and consumed a large number of crops that were "lost" to the world and only managed to exist through the cultivation by a few natives. Some surprising and interesting vegtetables are starting to be redistributed by genetic preservation organizations.
Having problems getting your kids to eat vegetables? A rediscovered root, maybe on a shelf near you soon, when baked becomes "butterscotch pudding". No, Im not kidding.
Are you allowed to tell us what it is? As a kid, I made sassafrass(sp) tea.