Good question T-bird... we have several large white oak trees and, although they are my favorites, I dread late July since that's when the acorns begin falling. The squirrels (we have five varieties) go crazy of course. The first ones to fall (nuts, not squirrels), like your hazel nuts, are immature, small and green... no matter, the squirrels either gnaw off the shell and bury them (can they possibly remember the location of all the buried nuts come winter?) or simply sit on their haunches looking (at least to me) quzzically at the emptiness in their paws, wondering, I suppose, where did the "stuff" go. (Then, there's the pulling up of all the oak seedlings from the strangest places, next spring.)
By the way, the most hilarious part of the show is when the big red fox squirrels repeatedly traverse the yard picking up more and more nuts until his jaw sacks simply can't hold anymore, and yet still trying to tuck one more in. Often, the try to carry one in a front paw... limping along all the way to their home tree... greedy little critters, no?
At any rate, it's somehow reassuring to know that nut producing trees, squirrels and observers of nature's comedy are the same on both sides of the Atlantic... (no real answer for you, was there?)...