Pleurisy Root, Asclepias tuberosa, is sometimes known as Butterfly Milkweed. Pleurisy Root is a strikingly beautiful herb. This plant and others of this genus are the main source of food for the Monarch Butterfly. Roots used to treat respiratory ailments and rheumatism. Pleurisy Root is native to Canada and North America. Requires rich peaty soils in an open sunny position. Produces tresses of brilliant bright orange or deep yellow flowers during summer. Frost resistant but drought tender. A perennial plant, growing to 1m x 1m.