Asclepias eriocarpa

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.[2]

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.[2]

The plant was used as a source of fiber and medicine by several California Indian groups, including the Ohlone and Luiseño.[3] The Concow tribe calls the plant bō'-kō (Konkow language).[4]

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).

• Jepson Manual Treatment: Asclepias eriocarpa
• Asclepias eriocarpa Photo gallery