Life (root) » Plantae (plants) » Tracheophyta (Vascular Plants) » Angiospermae (Flowering Plants) » Magnoliopsida (Dicots) » Gentianales (gentians, dogbanes, madders, and allies) » Apocynaceae (dogbane family) » Asclepiadoideae (milkweeds) » Asclepiadeae » Asclepiadinae » Asclepias (milkweeds) » Asclepias quadrifolia (four-leaved milkweed)