Bladdernut
Bladdernut, an ornamental shrub or small tree grown in the Northern Hemisphere. Of the many species, the most common is the American bladdernut, found in the United States and Canada. The shrub grows to a height of 8 to 14 feet (2.4–4.3 m). It has compound leaves and drooping, two-inch (5-cm) clusters of tiny white flowers. The pod containing the hard-shelled seeds is filled with air and resembles a bladder.
The American bladdernut is Staphylea trifolia of the family Staphyleaceae.