Echinacea angustifolia (Narrow-leaved purple coneflower, blacksamson echinacea) is a herbaceous plant species in Asteraceae. The plants grow 40 to 70 centimetres (16 to 28 in) tall with spindle-shaped taproots that are often branched. The stems and leaves are moderately to densely hairy.
E. angustifolia blooms late spring to mid summer. It is found growing in dry prairies and barrens with rocky to sandy-clay soils. There are two subspecies: E. a. angustifolia is native from Saskatchewan and Manitoba in the north to New Mexico, Texas, and Louisiana in the south, while E. a. strigosa has a more limited range in Kansas, Oklahoma, Texas, and Louisiana.[1[[|]]]
E. angustifolia is used as a fortifier of the immune system, mainly to prevent flu and minor respiratory diseases.[citation needed]Native Americans learned of E. angustifolia by observing elk seeking out the plants and consuming them when sick or wounded, and identified those plants as "elk root".[2[[|]]]