Senecio flaccidus |
Senecio flaccidus var. monoensis |
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Douglas' groundsel, Mono groundsel, shrubby butterweed, shrubby ragwort, threadleaf groundsel, threadleaf ragwort |
Mono groundsel, smooth threadleaf ragwort |
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Habit | Subshrubs or shrubs, (30–)40–120+ cm (taproots forming woody crowns). | |||||||||
Herbage | glabrous or ± lanate-tomentose. |
glabrate or glabrous. |
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Stems | usually multiple (little branched, arching-erect). |
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Leaves | ± evenly distributed; sessile or obscurely petiolate; blades narrowly linear to filiform (or pinnatifid, the segments linear to filiform), 3–10(–12) cm, bases ± linear, ultimate margins entire or remotely toothed (fascicles of smaller leaves sometimes borne in axils of larger leaves). |
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Involucres | campanulate. |
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Ray florets | usually ± 8 or ± 13, sometimes ± 21; corolla laminae 10–15(–20) mm (mostly yellow, sometimes ochroleucous). |
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Phyllaries | ± 13 or ± 21+, 5–10(–12) mm, tips green or minutely black. |
(± 13) ± 21, 7–10+ mm. |
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Calyculi | usually of 3–5+ bractlets (lengths often to 1/2+ phyllaries), sometimes 0. |
bractlets well developed (lengths, at least some, 1/2 phyllaries). |
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Heads | (1–)3–10(–20+) in corymbiform or subcorymbiform clusters, often gathered in larger, showy arrays (involucres campanulate or cylindric). |
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Cypselae | hairy. |
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2n | = 40. |
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Senecio flaccidus |
Senecio flaccidus var. monoensis |
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Phenology | Flowering mostly summer–fall, less commonly spring. | |||||||||
Habitat | Open, rocky or sandy sites, especially desert basins and washes | |||||||||
Elevation | 600–2000 m (2000–6600 ft) | |||||||||
Distribution |
AZ; CA; CO; KS; NM; NV; OK; TX; UT; Mexico
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AZ; CA; NM; NV; TX; UT; Mexico (Baja California) |
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Discussion | Varieties 3 (3 in the flora). The varieties of Senecio flaccidus are distinguished by morphologic tendencies and geography. The species occurs southward to central Mexico; a sound understanding of the infraspecific taxonomy must await revisionary studies that include the Mexican plants. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Senecio flaccidus var. monoensis intergrades with var. douglasii and with var. flaccidus in areas of range overlap. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 558. | FNA vol. 20, p. 559. | ||||||||
Parent taxa | Asteraceae > tribe Senecioneae > Senecio | Asteraceae > tribe Senecioneae > Senecio > Senecio flaccidus | ||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Synonyms | S. monoensis, S. filicifolius, S. lathyroides, S. pectinatus | |||||||||
Name authority | Lessing: Linnaea 5: 161. (1830) | (Greene) B. L. Turner & T. M. Barkley: Phytologia 69: 54. (1990) | ||||||||
Web links |