A genus of plants native to the waterways of Asia and the central and southern USA. They have pinnate leaves 30-35 cm long, composed of elongated oval leaflets that are dark green. They produce drooping panicles of fragrant flowers, blooming in late spring and summer, with the second bloom being less showy. The fruits are pods containing toxic seeds. They grow in all loose, permeable soils and are used to cover walls, slopes, old trees, and can be shaped into single trees with an irregular but highly ornamental crown.