: an orange-flowered milkweed of the genus Asclepias (A. tuberosa) of eastern North America that is a source of asclepias—called also pleurisy root
North American plant (Asclepias tuberosa) of the milkweed family (Apocynaceae), a stout, rough-haired perennial with long horizontal roots. The leafy, erect, somewhat branching stem is about 1–3 ft (0.3–0.9 m) tall. In midsummer it bears numerous clusters of bright orange flowers. Unlike most milkweeds, it has a scanty milky juice. It is native to dry fields and is often planted in wild gardens or grown as a border plant.