Corn plants; photo by Linda on Flickr (noncommercial use permitted with attribution / no derivative works).
Official State Grain of Wisconsin
Wisconsin designated corn as the official state grain in 1989 to bring attention to its importance as a cash crop in Wisconsin, and to make people more aware of corn's many uses, which include livestock feed, ethanol fuel, sweeteners, and biodegradable plastics. Corn is also featured on the U.S. Mint's Wisconsin quarter. All Food & Agriculture Symbols
Corn is native to the Americas, cultivated by native Americans at least 7000 years ago.
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