This question is driving me crazy because I haven't been able to figure out a query for what should be an easy answer. Here's an approach I find helpful: 1 - Search for the proper term for the characteristic with something like "retain leaves in winter" (Wikipedia page for "marcescence" shows up as 4th or so item). 2 - Perform an image search with that term; "marcescent trees" in this case. If lucky, you'll find BOTH a photo that matches what you're trying to identify AND a link to a website that includes a name. Here is a link that might be useful: Image search for marcescent trees

Hmmm...maybe...but I am all but positive these do not flower or fruit, and they don't look as vigorous as in the Duke pictures. They are prolific, though...plenty of seedlings/saplings and some 8-9' trees like this one. More time needed for it to leaf out, perhaps?

Looks like Lily of the Valley but it's not blooming. That's a low light plant but I think the blooms need a little light at least.

Brilliant! I was hoping that's what it was, although I've never seen a labeled or IDed specimen before. C. latifolium is one of my favorites.