When corn is ready to pick, carefully select the best ears, husk and silk them, leaving the last bit of stump-end (close to the ear) and the tip-end intact. The stump makes a good handhold, and the tip a good rest, when cutting the corn from the cob.
Work as quickly as possible in preparation so none of the goodness is lost. First, plunge the ears into a large covered kettle of boiling water for five minutes to set the milk in the kernels, then dunk them in cold water with ice cubes to stop the cooking.
After the corn is cooled enough to handle, cut the kernels off the cob, holding the ear upright by the little stump and using a sharp paring knife to cut downward toward the tip-end, being careful not to cut too close to the cob. Then scrape the cob, using the back of the knife, to get all the milk and kernel hearts.
Set the oven on warm, spread the corn evenly in large trays or cake pans to a depth of no more than one to one and a half inches, then slide the pans into the oven and leave them there for two or three nights or until corn is thoroughly dried. Mornings, take the trays out of the oven to rest and to free up the oven for other cooking. Stir the corn a few times each day to ensure even drying throughout. The dried corn will keep for any length of time with no additives whatsoever.
You can expect the corn to shrink up to as much as half its original bulk during the drying process. A gallon jar will hold the equivalent of five dozen ears. Coffee cans, canning jars and even plastic bags will serve as well whatever fits your storage capacity.