Senecio pseudoarnica Less. (redirected from: Senecio pseudo-arnica)
Family: Asteraceae
[Senecio pseudo-arnica Less.]
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Perennials, (15-)20-60(-100) cm (caudices erect). Herbage arachno-tomentose to sericeous-lanate (especially on abaxial faces of phyllaries), unevenly glabrescent. Stems single (turgid). Leaves evenly distributed (proximal withering before flowering); subsessile or petiolate; blades obovate to oblanceolate, 5-15(-25) × 2-6(-10) cm, bases tapered, margins serrate-dentate to denticulate or subentire (distal leaves slightly smaller). Heads 1-5(-15+) in corymbiform arrays (involucres notably large, 20-40 mm diam.). Calyculi of 6-10 linear bractlets (longest nearly equaling phyllaries). Phyllaries ± 21, 8-15 mm (sometimes purplish or pinkish-tinged), tips greenish. Ray florets usually ± 21, rarely 0; corolla laminae 20-25 mm. Cypselae glabrous. 2n = 40.

Flowering summer. Sandy-gravelly ocean shores and upper beaches; 0 m; St. Pierre and Miquelon; B.C., N.B., Nfld. and Labr., N.S., Que.; Alaska, Maine; ne Asia.

Rayless individuals of Senecio pseudoarnica have been recognized as var. rollandii or forma rollandii (Victorin) Fernald; they are not otherwise distinctive.

Stout perennial 1-7 dm, thinly tomentose or partly glabrate; lvs early deciduous near the base of the stem, otherwise persistent, crowded, and only gradually if at all reduced upwards, oblanceolate to obovate, 7-20 נ1.5-7 cm, coarsely toothed to subentire, the lower commonly tapering to the petiole or petiolar base; heads 1-5, very large, the disk 2-4 cm wide; invol 10-16 mm; rays ca 21, 1.5-2.5 cm (rarely wanting); achenes glabrous; pappus very copious; 2n=40. Sea-beaches; Me., N.B., and the lower St. Lawrence R., n. to the Arctic; Alaska and Siberia. July, Aug.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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