Senecio

Senecio, the most numerous genus of the great natural order Compositæ, having a hairy pappus, a naked receptacle, and a cylindrical involucre of linear equal scales, with a few smaller scales at their base. The species are annual, perennial, and half-shrubby plants, natives chiefly of the temperate and cold parts of the world, the half-shrubby species being from the warmer latitudes. Eleven species are reckoned as British, and commonly known as Groundsel (q.v.) and Ragwort (q.v.). S. Saracenicus, probably not a true native of Britain but introduced in the middle ages, has undivided lanceolate leaves, and was once in repute as a vulnerary. The Fireweed of North America is S. hieracifolius. It receives its popular name from its appearing abundantly wherever a part of the forest has been consumed by fire. Many species of Senecio have a strong, disagreeable smell. A few are rather ornamental as flowers; see CINERARIA.