Sorry I disappeared for a while.
The parent tree was growing in my backyard when I was a kid, It was a huge tree! It mysteriously started dying. From what I remember (I was around 11yrs old) the people who came out to remove it said it was a American elm that had dutch elm disease. They just cut the tree down to about a 1ft stump & left it. About a year later this little tree started growing right next to the stump. I do remember the parent tree having very fissured dark bark almost pine tree type of bark. I will have to go though some old pictures because I know I have a few with that tree in it.
I uploaded a few pictures of the leaves. The big leaf is about 2-3" but the others I would say under 1/2" or so. The smaller leaf is the normal for this tree. I cut it back a few months back & it just blew up with growth so the leaves have gotten quite large.
I never looked it up to make sure what it really was I always assumed it was a American elm.
If that grew right next to the stump of the Elm tree they removed due to Dutch elm disease, then it probably grew off it's roots. Elms will frequently do that, send shoots up off of roots especially when the parent is cut back hard and the roots are near the soil surface... If that is the case, it is technically the same tree, and I suspect it is likely infected. Hard to tell on a tree of this size and age I guess... How did that top die? Dutch Elm disease is a fungal thing and though the fungus is spread from one tree to another normally by Beatles... I suspect the shared roots give a high probability of shared disease.
Good luck, hope I am wrong, maybe the tree is fine... I would remove the dead wood down tot he next branch, remove the suckers from the base and let the leader grow for a couple years to see what it does. If it stay healthy, you can develop some taper that way, maybe a bit of movement and form your crown from that. If it is happy, like most Elms you will probably get an insane number of new shoots at random locations along the trunk.
