Squirrels know exactly how well the nuts and acorns they find can stay preserved, which means that when they find nuts they know which ones to bury at which time and where. They also have a process to make acorns last longer: taking out the embryo!
They're also really sneaky. Give a squirrel some nuts and he'll dig several "dummy" holes for each actual nut that he buries. This throws off other animals watching them who would try to steal their food. Sometimes they even pretend to bury nuts to send their competition on a wild goose chase.
