When drying wet wheat with natural air, fans
should be run day and night until the moisture
content drops to about 15 percent. Wheat on the
bottom of the bin is the first to dry, especially
during hotter and drier daytime hours. As the air
passes through the lower layers, it removes moisture
from the wheat on the bottom layers and
eventually becomes saturated so that it can’t hold
any more moisture. Hence, the wheat on the top
layers does not dry until the wheat in the bottom
layers is relatively dry