It is a lovely double ROS, and it's been made a standard (tree form) on purpose. I have several in tree form in bloom right now and they make dandy little trees for the right situation. What is all that foliage, however, inside the wire cage? If it's sprouts off the ROS, they should be removed. Yes, barberry will also throw out babies, but it's not rampant if you maintain your plantings and easily pulled. I don't 'prune' them any more than necessary because it interrupts their lovely, natural shapes and turns them into bowling ball hedges. Definitely one of the more deer proof shrubs, if that is an issue. BTW, I've never had deer rub or browse on my ROS, either. They tend to go for the expensive, rare stuff. LOL.

Euonymus alatus, burning bush (a shrub rather than a tree).

I would definitely want a closeup of the leaves in your hand before going any farther than, “it appears to be a tree.”

Christopher, my photo of the larger thicket might be pensylvanica. P. pensylvanica is scarce in my area, and is mostly found in sandy areas like Dunes. There is only one observation for it in my county, whereas there are many observations for P. serotina. I have a small prunus that I think is serotina, and the leaves are smooth on the underside with no pubescence, and I see no nectary glands at all, so it's very hard to tell the leaves apart. The flowers are different though. P. serotina, P. pensylvanica, and P. persica each have distinct flowers.