I'm gonna have to agree with LW. I think she nailed it. When looking in my "Knowing Your Trees" book, the leaves and nut match up to Shellbark Hickory, Bigleaf Shagbark Hickory, Kingnut, Big Shellbark. This would be different names for the same tree.
A friend of mine gave me some dried hickory he had in his firewood pile. I mounted a chunk on my woodlathe, forgetting I had the speed to highm, and slung that sucker clear across the shop. Sure glad it didn't hit me. I slowed down the lathe and made several real purty woodworking mallets. That is some tough wood that hickory.
