Corn Sweat Worsens Midwest Heat Wave

The heat wave punishing the central United States feels extra brutal this week. It sounds bizarre, but millions of acres of corn are actually making the weather worse.

"Corn actually produces humidity, if you will, or moisture that wicks off the plant on average about 4,000 gallons per acre per day," says farmer Mark Baker.

That moisture doesn't just disappear. It hangs in the air, driving humidity levels higher and making hot days feel miserable.

Plants That Change the Weather

Meteorologists call it "corn sweat," though the technical term is evapotranspiration. Whatever you call it, the effect is real and measurable. Corn releases far more moisture than other plants—about 40 times more than a mature oak tree, which puts out roughly 100 gallons daily.