Ah, yes, late July in the Midwest: a time for popsicles by the lake, a trip to the county fair, and, of course, extreme humidity made more miserable by…corn sweat.

Corn sweat. It’s a thing!

The term refers to the moisture released by fields of corn during hot and sunny weather. Like all other plants, corn transpires — meaning, it sucks up water from the ground and expels it into the air as a way to stay cool and distribute nutrients. Moisture also enters the air when water in the soil evaporates. Together with transpiration, this process is called evapotranspiration.

So, where you find loads of plants packed tightly into one place, whether the Amazon rainforest or Iowa, humidity can skyrocket during hot and especially sunny periods, making the air feel oppressive.

That’s what’s happening this week: A massive heat dome is bringing dangerously high temperatures to much of the US, including parts of the Midwest where there also happens to be vast fields of corn. Along with plenty of sunlight, that heat is enough to make corn sweat, producing extremely uncomfortable weather and, in some areas, a heat index of 110 degrees or higher.

It’s not that corn sweats more than........

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