Senecio triangularis |
Senecio warnockii |
|
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arrow-leaf groundsel, arrow-leaf ragwort, arrowleaf butterweed, groundsel |
Warnock's ragwort |
|
Habit | Perennials, (20–)50–120(–200) cm (caudices branched, ± woody). | Subshrubs, 20–40 cm (taproots forming woody crowns). |
Herbage | glabrous or sparsely floccose-tomentose when young. |
closely, unevenly lanate-floccose, glabrescent. |
Stems | single or loosely clustered. |
usually multiple (strict or nearly so, arching-erect). |
Leaves | evenly distributed; petiolate; blades narrowly triangular, (3–)4–10+ × 2–6 cm, bases usually ± truncate, sometimes tapered, margins usually dentate, rarely subentire (distal leaves subsessile, smaller). |
(often recurved and thickish-turgid) concentrated distally on stems; sessile or obscurely petiolate; blades narrowly linear to filiform (2–7 cm × 1 mm), bases ± linear, margins entire. |
Ray florets | ± 8; corolla laminae 9–15 mm. |
usually ± 8, rarely 0; corolla laminae 5–10 mm. |
Phyllaries | (± 8) ± 13 (± 21), 6–10 mm, tips usually green, rarely black. |
± 13, 5–8 mm, tips green or minutely black. |
Calyculi | of 2–6 bractlets (rarely more than 2 mm). |
0 or of 3–5 bractlets (lengths less than 1/2 phyllaries). |
Heads | 10–30(–60) in corymbiform to subracemiform arrays. |
3–10 in corymbiform arrays (involucres weakly campanulate). |
Cypselae | glabrous. |
glabrous. |
2n | = 40, 80. |
|
Senecio triangularis |
Senecio warnockii |
|
Phenology | Flowering summer. | Flowering fall (perhaps spring–summer). |
Habitat | Damp places, open woodlands, especially rocky stream banks in coniferous forests | Open sites, gypseous soils |
Elevation | 100–3300 m (300–10800 ft) | 800–1500 m (2600–4900 ft) |
Distribution |
AK; AZ; CA; CO; ID; MT; NM; NV; OR; WA; WY; AB; BC; NT; YT; PH
|
NM; TX |
Discussion | Plants of Senecio triangularis with narrow, subentire leaves that taper to the petioles are occasionally encountered in acid bogs in Oregon and Washington and less frequently elsewhere. They are regarded as edaphic variants; they have been recognized as var. angustifolius. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Senecio warnockii is infrequently collected; additional study may show it to be an edaphic phase of S. flaccidus. The restriction to gypseous soils and the gross aspect combine to make it distinctive. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 566. | FNA vol. 20, p. 559. |
Parent taxa | Asteraceae > tribe Senecioneae > Senecio | Asteraceae > tribe Senecioneae > Senecio |
Sibling taxa | ||
Synonyms | S. gibbonsii, S. saliens, S. triangularis var. angustifolius | |
Name authority | Hooker: Fl. Bor.-Amer. 1: 332, plate 115. (1834) | Shinners: Sida 1: 379. (1964) |
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