Chaenactis douglasii |
Chaenactis nevii |
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chaenactis, Douglas' dusty maidens, Douglas' dustymaiden, hoary chaenactis, hoary false-yarrow, hoary pincushion |
John Day pincushion, John Day's pincushion, Nevius' chaenactis |
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Habit | Biennials or perennials, (2–)5–50(–60) cm (rarely slightly woody or flowering first year, sometimes cespitose or ± matted); proximal indument thinning with age, grayish, mostly arachnoid-sericeous to thinly lanuginose. | Plants 10–30 cm; proximal indument greenish to grayish, stipitate-glandular and, sometimes, sparsely arachnoid or villous. | ||||
Stems | 1–25+, erect to spreading. |
mostly 1–3; branches mainly distal. |
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Leaves | basal, or basal (sometimes withering) and ± cauline, (1–)2–12(–15) cm; largest blades ± elliptic or slightly lanceolate to ovate, ± 3-dimensional, usually 2-pinnately lobed; primary lobes (4–)5–9(–12) pairs, ± congested, scarcely imbricate, ultimate lobes ± involute and/or twisted. |
basal (withering) and cauline, 2–5 cm; largest blades ± elliptic, ± plane to 3-dimensional, not succulent, 1–2-pinnately lobed; primary lobes mostly 3–8 pairs, ± remote, ultimate lobes ± plane to involute. |
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Peduncles | mostly ascending to erect, 1–10 cm. |
1–6 cm, distally stipitate-glandular and, sometimes, ± arachnoid to villous. |
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Involucres | obconic to ± hemispheric. |
± hemispheric to campanulate. |
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Florets | corollas bright yellow, 4–6.5 mm; peripheral corollas ± erect, actinomorphic, scarcely enlarged. |
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Corollas | 5–8 mm. |
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Phyllaries | longest 9–15(–17) mm; outer usually stipitate-glandular (sometimes sparsely or obscurely, rarely eglandular) and, often, arachnoid to lanuginose and, sometimes, sparsely villous, apices usually ± squarrose, pliant. |
longest 6–9 mm; outer predominantly stipitate-glandular and, sometimes, ± arachnoid to villous in fruit, apices ± erect, acute, rigid. |
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Heads | 1–25+ per stem. |
mostly 3–9 per stem. |
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Cypselae | 5–8 mm (usually sparsely glandular amidst other indument); pappi: longest scales 3–6 mm. |
3.5–6 mm (compressed); pappi 0 or coroniform (of ± 10 scales, longest 0.1–0.5 mm). |
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2n | = 12. |
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Chaenactis douglasii |
Chaenactis nevii |
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Phenology | Flowering late Apr–mid July. | |||||
Habitat | Nearly barren, heavy clay soils from volcanic ash and tuff, sometimes disturbed or moist sites | |||||
Elevation | 400–1000 m (1300–3300 ft) | |||||
Distribution |
AZ; CA; CO; ID; MT; ND; NM; NV; OR; SD; UT; WA; WY; AB; BC
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OR
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Discussion | Varieties 2 (2 in the flora). Chaenactis douglasii is widespread and variable (see discussion under var. douglasii). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Chaenactis nevii is known from the John Day Basin area in Gilliam, Grant, Jefferson, Wasco, and Wheeler counties. This odd and isolated species combines traits of C. artemisiifolia (sect. Acarphaea) and C. glabriuscula, and might be descended from their common ancestor. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 21, p. 405. | FNA vol. 21, p. 411. | ||||
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Chaenactis > sect. Macrocarphus | Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Chaenactis > sect. Chaenactis | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Hymenopappus douglasii, Macrocarphus douglasii | |||||
Name authority | (Hooker) Hooker & Arnott: Bot. Beechey Voy., 354. (1839) | A. Gray: Proc. Amer Acad. Arts 19: 30. (1883) | ||||
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