Acer triflorium???

I've never head of that. What is the common name?

Do you mean Triflorum?
Or do you mean trident maple (Acer buergerianum)?

The oval habit and washed out color you describe makes me think trident maple but I didn't know they were hardy north of z6 or 7.

That's a good point: trident maple may have persistent leaves and has the synonym A. trifidum.

If it is in fact Acer triflorum, then more sun would likely improve your coloring in the fall.

Yes, I apologize. Triflorum! I should have looked it up before hitting the send button.

I'm not too concerned about the fall color. Under-stated is OK in that regard as long as I've got the leaves hanging on through the winter as my existing specimen's leaves do. Screening is more important than fall color in this part of the yard and a small tree works better than shrubbery in this location because the street in that direction is elevated a few feet higher than the location where the A. trifolium is located and where I'd put another.

I've got plenty of fall color with the Hamamelis Jelena, C. florida, mas and kousa along with giant red and Michauxii oaks, redbuds, a Parrotia and several different Viburnum shrubs. The Calycanthus 'Athens' also has pretty good fall color as do some of my Lilacs. So, clearly, I can get by without another point of notable color.

Thanks...