woollypod milkweed

Asclepias eriocarpa is an erect perennial herb which is usually coated in a thick layer of white hairs. The leaves are lance-shaped to oval, rippled, and arranged oppositely in pairs or in whorls of 3 or 4. The inflorescence is a large umbel-like cluster of flowers. Each flower is white to cream and usually tinted with bright pink. It has a central array of rounded hoods and a corolla reflexed against the stalk. The fruit is a large, woolly follicle. Flowers bloom May to October.

Asclepias eriocarpa is native to California and adjacent parts of Nevada and Baja California. It grows in many habitat types such as rocky hillsides, woods, deserts, and especially dry areas.

Asclepias eriocarpa is a specific monarch butterfly food and habitat plant. It is one of the most poisonous milkweeds. Natural History July/August 2015 calls it the most poisonous, but most sources put it below A. lancifolia (now known as Asclepias perennis).

Several Californian Indigenous groups, including the Ohlone and Luiseño, used this plant as a source of fiber and medicine. The Concow tribe calls the plant bō'-kō (Konkow language).