The bottle-like taper to this tree's trunk gives it its common name.
Ovate to palmately lobed leaves have long petioles, allowing them to quake easily in the wind.
Small (3/4") creamy yellow bell-shaped flowers have a reddish throat. Flowers are present May through July.
Flowers held in terminal 4"-6" panicles.
Fruits are pointed woody ovoid follicles held palmately in clusters of five or more. Follicles are densely hairy inside and burst open along one seam to expose light colored oval seeds. Fruit is present in late summer.
Smooth green, darkening to brown bark with white furrows.