Farmer: Because water content is what makes popcorn pop, the kernels must dry at just the right speed to trap the correct amount of water. The best way to achieve this effect is to have the sun dry the corn while the corn is still in the field, but I always dry the ears on a screen in a warm, dry room.
The statement 'When popcorn does not dry sufficiently, it will still pop, but it will take several minutes to do so, even under optimal popping conditions' most helps to resolve the apparent discrepancy between the farmer's theory and practice.