Cornfields cause more fog late-summer

It's the dog days of summer and you may often notice fog hanging over fields of corn every morning. We have received quite a few photos from viewers showing not only gorgeous sunrises, but also misty fog draping the corn fields. It makes for a picturesque morning, and it is not something that we can see year round at this frequency, it's only common when the corn stalks are nearly full size and have a lot of surface area.

The fog forms as a result of evapotranspiration. The corn stalks absorb water from the ground and release the water through their leaves in the form of vapor. This process is transpiration. The ground also releases moisture through evaporation. During the morning hours the air is always the most saturated, so this causes the water vapor from the corn stalks and ground to condense near saturation as well, forming a layer of fog over the fields.