The genus Senecio is one of the largest among higher-plant genera: it embraces about 1,500 species distributed literally all over the globe from tiny plants of the tundra belt to the so-called rosette trees of African tropics! Among Senecio species there are annuals, biennials, perennials, vines, shrubs, subshrubs, succulents... Gray called Senecio "a tremendous genus."