Chaenactis douglasii |
Chaenactis santolinoides |
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chaenactis, Douglas' dusty maidens, Douglas' dustymaiden, hoary chaenactis, hoary false-yarrow, hoary pincushion |
santolina chaenactis, santolina pincushion |
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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. | Perennials, 10–25(–35) cm (cespitose or ± matted); proximal indument thinning with age, whitish to grayish, lanuginose. | ||||
Stems | 1–25+, erect to spreading. |
mostly 5–15+, erect to ± spreading. |
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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, (1–)3–11 cm; largest blades linear-cylindric to ± fusiform, 3-dimensional, 1–2-pinnately lobed; primary lobes (7–)10–18+ pairs, ± imbricate, ultimate lobes ± involute, twisted. |
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Peduncles | mostly ascending to erect, 1–10 cm. |
mostly ascending to erect, mostly 8–25 cm. |
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Involucres | obconic to ± hemispheric. |
obconic to ± cylindric. |
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Corollas | 5–8 mm. |
5–7 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 8–13 mm; outer evidently stipitate-glandular and, sometimes, ± arachnoid, apices erect, ± rigid. |
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Heads | 1–25+ per stem. |
1(–3) per stem. |
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Cypselae | 5–8 mm (usually sparsely glandular amidst other indument); pappi: longest scales 3–6 mm. |
4–6 mm; pappi: longest scales 3–4.5 mm. |
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2n | = 12. |
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Chaenactis douglasii |
Chaenactis santolinoides |
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Phenology | Flowering (Mar–)May–Jul. | |||||
Habitat | Exposed sandy to rocky summits, ridges, scree, talus, openings in or above conifer forests, sometimes road cuts or other recent disturbances | |||||
Elevation | (1100–)1500–2800 m ((3600–)4900–9200 ft) | |||||
Distribution |
AZ; CA; CO; ID; MT; ND; NM; NV; OR; SD; UT; WA; WY; AB; BC
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CA
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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.) |
Of conservation concern. Chaenactis santolinoides is known from the southern Sierra Nevada and Transverse Ranges. It is sometimes cultivated in rock gardens and may be found beyond its native range. It may be relatively recently derived from an isolated segment of C. douglasii var. alpina. The morphology of C. panamintensis (here assigned to C. douglasii var. alpina) suggests past convergence toward, or genetic influence from, C. santolinoides. (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. 407. | ||||
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Chaenactis > sect. Macrocarphus | Asteraceae > tribe Heliantheae > subtribe Chaenactidinae > Chaenactis > sect. Macrocarphus | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Hymenopappus douglasii, Macrocarphus douglasii | |||||
Name authority | (Hooker) Hooker & Arnott: Bot. Beechey Voy., 354. (1839) | Greene: Bull. Torrey Bot. Club 9: 17. (1882) | ||||
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