OK, got another one for you. There's a tree that I've wondered about in a neighbor's backyard, but I couldn't get a decent photo of it. Weird tree! Dark, thickly ridged lower trunk, but the upper branches are smooth and white like a birch. I thought it was an anomaly (maybe one tree sprouted from the trunk of another?) until I spotted this similar example:
Got any ideas?
Y'all were able to name the last mystery tree (a sycamore) quite handily, so I'm sure you'll be able to help me out here, too.