If you choose to wait until hulls turn black they are easier to shell, but if you don't wear rubber gloves the messy hulls will stain your hands brown. At this stage the moisture content of both shell and meats is high. Place the hulled nuts in a burlap bag or onion sack and store them out of the weather. About mid-December they should be ready for cracking. If you like chestnuts, now is the time to harvest Chinese chestnuts.
Harvesting is much more critical for chestnuts than pecans or walnuts.
If a chestnut is allowed to stay on the ground for more than 2 or 3 days, it will soon become inedible and turn a white color. As chestnut burs open they should be harvested within a day or so and planced in a semishaded area for a couple of days and then refrigerated or frozen.