Very possibly a hickory. I think you're spot on in the genus. But the end leaf is more pointed on mine than on the black hickory. Perhaps is it this white hickory or Mockernut Hickory: https://www.thoughtco.com/mockernut-hickory-tree-overview-1343190

https://www.forestryimages.org/browse/detail.cfm?imgnum=1582130

Looks a lot like my pecans.

Yes, my first thought was a pecan. But the distinctive, dead-give-away pungent pecan leaf odor isn't present. It also looks a lot like an Ash leaf, but I think ash leaves are much smaller/slimmer than these.

Walnut? Is there anything growing around it?

Just another one of the same plant (also still in its trade pot) that is 100% dead from lack of water and care. I'm going to nurture this live one hopefully back to a healthy state and just wait and see what grows. I think it's some kind of nut tree. Time will tell, if I live long enough to se it produce "fruit". LOL

Looks to be a tree in the Juglandaceae family which include pecans, hickory, and walnuts.

Is there not a label on the pot? Or maybe someone dug up something unknown and plunked it in the pot to give away.

It looks a lot like the nogalito trees (Texas Walnut) we have growing here, though it's hard to say from the photos. They're an understory to our escarpment oaks with light gray smooth bark and a leaf pattern like yours. Squirrels eat the walnuts -- they're too small and hard for human consumption.

No nursery label on pot or tree. I think the Nogalito has slimmer leaves than this specimen. My plant's leaves are QUITE large and wide.

OK, mystery tree finally identified. Why the leaves did not have the distinctive pecan odor when crushed last year is still a mystery. But yesterday while watering plants at the cabin, I crushed some more leaves and it IS INDEED a pecan tree. I'm kind of glad that's what it is after all. So all of us that thought that up front were right! Of course, I'll probably be dead and gone before this 6' tree produces a pecan, but somebody will enjoy something besides hickory nuts (mostly what's down there). Never see squirrels, that love hickory nuts, because the daily hawks and a few copperheads have likely scared them all off.

I've not gotten up the nerve to taste a hickory nut yet, but they are edible, I have read. We have bazillions of them on the ground each year. I hate stepping on them but also don't want to pick them all up, unless we can find an efficient/fast way to do that without killing my very bad back.

YAY! What do we win if we were right ? :-) wink, wink I have a lot of pecan seedlings come up in the yard, so I was pretty confident. Don't be so sure that you won't get pecans sooner than later! We left a few squirrel-planted pecans in our yard next to some mesquites, in order to have shade as the mesquites fall apart. A few years ago we started getting pecans, very surprised that they showed up so quickly!

CG, you get the first pecans I get from it shelled and ready to eat! Like I said, I wouldn't hold my breath on that prize. LOL