A semi-woody plant which sends up erect, pithy shoots 2 to 3 ft high each year, furnished with pinnate leaves 6 to 10 in. long, each composed of an even number of leaflets, usually seven to nine pairs. Leaflets 1 to 21⁄2 in. long, oblong, the midrib terminating in a bristle. Racemes 2 to 3 in. long, terminal or springing from the axils of the leaves; the almost regular flowers crowded towards the end, 1⁄2 in. across; petals yellow, nearly alike; anthers a conspicuous dark purple. Pod 3 to 4 in. long, covered with grey hairs when young.
Native of the south-eastern United States; introduced to England in 1723. It flowers from the end of July until October, and is very handsome then. A sheltered position should be found for it, and, as it is not absolutely hardy in all winters, it is wise to cover the root-stock with a few inches of light litter in severe weather. It can be propagated by breaking up the old root-stock just as growth recommences in spring, and if the pieces can be given a mild bottom-heat and re-established in pots for planting out later, so much the better. But imported seeds can be obtained, and they, of course, give the best and simplest means of increase. The plant has certain cathartic properties resembling those of senna.