Probablly Hickory Nuts. I don' t think deer eat them, but, I am not entirely sure of that. I do however know that squirrels absolutely LOVE those things. I have a HUGE hickory tree in my woods that I call the " squirrel tree" . It is hollow from the base to the top, and this thing is FULL of squirrels. The bottom of the tree is open on both sides, and each fall, this little area gets PACKED with hickory nuts by these squirrels!