suggest either a YOUNG (before it develops the "shaggy" bark) shagbark (carya ovata) or perhaps mockernut (c. tomentosa) hickory????.

You can get a best idea from the # of leaflets per "stem"

7-13 pecan
5 = shagbark hickory
7 = shellbark hickory

the other unedible hickories I'm not fluent to identifying.
Pignut however is 5 and not very often 7. So it's not pignut.

always count several leaflet groups because with all, there is occasionally an oddball number. on shagbarks you may see 7 at times but the other 95% of the time it's always 5.

I see 7 mainly on your sample. Check the length and width of the leaves and compare it to shellbark hickory and if that doesn't match then begin to cross check with other species.

Dax

My guess would be that its a hickory and not a pecan. Both from the bark (texture and color) and the leaves (their color and shape). Maybe mockernut?

Not enough details, but the interlacing ridges look like pignut/mockernut. The number of leaves on a very small tree can vary enough to make IDing difficult from that, tho my shellbark even small had much larger leaves.

Definitely hickory.
Trunk is still small enough that it's just now beginning to exhibit some bark characteristics - but probably not enough yet to make the call on whether it's pignut or mockernut, shagbark - or even red hickory(C.ovalis).
But, I'm leaning toward pignut or red hickory...