Ailanthus altissima

Here is a link that might be useful: Tree-of-heaven

That's what I thought when I first saw the picture (OP also posted in Weeds), but I thought that Ailanthus does not have a terminal leaflet. I can't see the notch on the leaves, either, but that may be the angle of the picture.

AndiC, what does it smell like when you cut or crush the leaves or stalk?

It smells like old peanuts.

Terminal leaflets seem more common on younger sprouts.
There's one clearly visible in the link I posted above.

The other tree this looks similar to is the staghorn sumac, Rhus typhina. But I believe that you are way out of that tree's normal range. There may be other sumacs that have a similar look when young but I'm not familiar with them.

Anyways, the staghorn sumac has a very fuzzy and downy trunk at this age and it might be something you could check.

FataMorgana