Following the rate of drydown using kernel milkline is a good way to predict the order fields should be harvested. In a typical year a common benchmark is that fields should be dented by the first week in September. Kernel moisture at black layer will average 32 to 35 percent. The tightness of the husk, thickness of the seed coat and daily weather conditions influence the speed of kernel drydown. After black layer formation several hard frosts followed by sunny weather with temperatures in the 80's and a slight breeze is the ideal drying environment.
Hybrids differ in the time it takes to reach harvest moisture from black layer.
Scout for corn standability. Fields that have lodging problems can be identified and targeted for the earliest possible harvest. Look for visible symptoms and test stalk firmness by pinching the lower internodes with your thumb and forefinger. Healthy stalks are firm and can't be compressed. If a stalk can be compressed or feels soft, it is rotted and is a good candidate for lodging.