Staphylea trifolia
Staphyleaceae

As with fringtree (May 13), I don’t have any pictures of an entire specimen, because I’ve never seen one that wasn’t crowded in among other trees and shrubs.  Whereas you’re likely to find fringetree on bluffs, you’ll find bladdernut right along the river.  It, too, is an understory tree, but one that prefers a bit more light and a lot more water.

Bladdernut is more of a Mid-Atlantic and Midwest tree, fairly common throughout its range.  It’s small, usually standing about 12 feet tall or less, and unremarkable except for the lovely flowers.  And interesting seed-pods.