What kind of tree is this?

[FiragaDemon]

A few of these trees sprouted up in pots I had on my deck. This one is doing the best. I was hoping someone could tell me what is was, and also how to best take care of it. I plan on keeping it in a pot.

[img]https://img269.imageshack.us/img269/994/sdc10011t.jpg[/img]

Thanks!!

[Woolly]

Do you have any choke cherry trees near by? It almost looks like ones that are coming up around our place. We have both the red and the green types, and that one in your pic looks just like it.....

[!potatoes!]

looks like there's a couple of compound leaves near the top, which would rule out cherries of any kind...my guess is a nut of some kind - hickory, walnut, pecan, something like that...transplant it, it may become obvious.