Harvesting acorns is of interest to different people for different reasons. Some gardeners have the desire to grow their own massive oak trees from tiny acorns. Others love eating the tasty little morsels. Acorns are commonly sought for use in handcrafts, and lots of folks just like collecting them to help their wildlife friends through the winter. Whatever your purpose, oak trees are easy to harvest and the bounty is free for the taking. Depending upon the oak tree variety and your location, acorns will drop from late September through October.
Choose a large mature oak tree. Typically the bigger and healthier a tree is, the more abundant its crop of acorns will be. Watch your chosen oak beginning early in September, when it will begin dropping mature acorns. You'll be competing with local wildlife, so be ready to grab the acorns quickly in order to get your fair share.
Check the maturity of the tree's acorns every day. Once they begin falling naturally, you can pluck others right from the tree. Pick a few of the nuts with uniformly golden brown color. If they're ripe enough, the caps will slip easily from their tops with a nudge from your thumb. If the tops don't pop right off, the acorns are still immature and too green to use.
Harvest newly fallen acorns from the ground if the weather has been dry. Nuts ripen on the tree and loosen from their caps upon reaching maturity. They fall to the ground naturally while leaving their tops attached to the tree's stems. Choose those which don't have any blemishes, splits, holes or spots on them. Don't collect nuts that you know have been laying around for a few days, because even the ever-vigilant squirrels have passed them by.
Drop the acorns into an old pillowcase. Quickly scribble a note indicating the tree's species and location, and drop it in with the nuts. If you're not going home right away, keep the acorns shady, cool and dry.
Refrigerate the bag of acorns as soon as possible for further processing.