Pentanema helveticum

Pentanema helveticum, commonly known as Swiss fleabane and formerly placed in the genus Inula as Inula helvetica, is an erect rhizomatous perennial herb in the family Asteraceae native to mountainous regions of central and southern Europe, including the Alps, the Jura, the Pyrenees and parts of the Balkans, where it occurs in damp meadows, stream banks and the margins of upland hay fields. Plants grow 40 to 120 centimetres tall from a creeping rhizome, with stout, finely grooved, sparsely hairy stems that are typically unbranched below the inflorescence. The alternate stem leaves are lanceolate to elliptic-lanceolate, 5 to 15 centimetres long, sessile and partly clasping at the base, with finely toothed margins, a deep green upper surface and a paler, softly hairy underside. The inflorescence consists of several to many bright golden-yellow flower heads 2 to 3.5 centimetres across borne in an open corymb at the stem apex. Each head has narrow ray florets surrounding a dense yellow disk, subtended by an involucre of several rows of narrow, often outwardly recurved green to brown bracts. The fruits are short, ribbed achenes 1 to 2 millimetres long crowned by a single row of slender white pappus bristles.