What Is Corn Sweat?
It’s so hot this summer, even the corn is “sweating.”
When the mercury soars, it’s not just the sun that makes the air feel stifling. If you spend the season in the Midwest, you may already be familiar with the phenomenon called “corn sweat” causing already oppressive summer heat waves to feel even more uncomfortable. Rooted in plant biology, the natural process contributes to the region’s high humidity levels that push the heat index even higher during peak growing season.
While corn sweat doesn’t create storms or control weather patterns, it does act as a localized amplifier in the Midwest, intensifying that sticky feeling you get when you walk outside on a hot summer afternoon.
See more: Farm Flavor Guide to Corn
What Is Corn Sweat?
The nickname “corn sweat” refers to the scientific process of evapotranspiration, or the process in which plants release water vapor into the atmosphere. Like all plants, corn takes up water from the soil through its roots and then releases some of it through pores in the plant’s leaves.
During the summer, when the corn plants are tall and fully grown, a field can release huge amounts of water vapor into the air. According to one U.S. Geological Survey study, just 1 acre of corn can give off a whopping 3,000 to 4,000 gallons of water per day. In Midwestern states like Illinois, home to nearly 11 million acres of corn, and Iowa, growing nearly 13 million acres, that adds up to tens of billions of gallons each day. All that water vapor then combines with other water molecules in the air to increase humidity, making hot conditions even more unpleasant.
Corn Sweat vs. Weather Patterns
While corn sweat undoubtedly contributes to higher moisture levels in the air, weather patterns remain the most significant factor in heat and humidity across the Midwest. All the extra water vapor released from cornfields can intensify the humidity on a more localized level, making hot days feel even hotter, but large-scale weather systems ultimately drive the region’s climate.
See more Field Corn and Sweet Corn: What’s the Difference?
Does Corn Sweat Have Benefits?
Despite making the summertime feel even muggier, corn sweat is actually a sign of a healthy crop. Just like sweating cools people, transpiration cools plants and protects them from heat stress. The process of evapotranspiration also helps corn release excess water taken up from the soil and is vital to the plant. If it stopped sweating, that would signal that the plant was stressed or suffering from drought.