Senecio vulgaris
Common groundsel, birdseed, ground glutton, chickenweed, common butterweed, grimsel, grinsel, grundsel, grundy swallow, old-man-in-the-spring, ragwort, simson, squaw weed
Description: winter or summer annual
Place of origin: Eurasia
Urban habitat: commonly found in neglected residential and commercial landscapes, vacant lots, waste dumps, stone walls, pavement openings; thrives in moist soils and full sun.
Ecological function: disturbance-adapted colonizer of bare ground; food for some birds and insects.
History: Senecio vulgaris arrived early in North America, probably brought by European colonists who valued the plant for its medicinal uses, including use as a diuretic, purgative, and in the treatment of menstrual disorders and nose bleeds. All parts of the plant are toxic to many mammals, including humans, affecting the liver slowly over time cumulatively.