Jepson Flora Project: Jepson Interchange    

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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California

  • Up-to-date information about California vascular plants is available from the Jepson eFlora.



David J. Keil, Family Editor and author, except as specified

Annual to tree
Leaves basal or cauline, alternate to whorled, simple to compound
Inflorescence: 1° inflorescence a head, each resembling a flower, 1–many, generally arrayed in cymes, generally subtended by ± calyx-like involucre; flowers 1–many per head
Flowers bisexual, unisexual, or sterile, ± small, of several types; calyx 0 or modified into pappus of bristles, scales, or awns, which is generally persistent in fruit; corolla radial or bilateral (rarely 0), lobes generally (0)4–5; stamens 4–5, anthers generally fused into cylinder around style, often appendaged at tips, bases, or both, filaments generally free, generally attached to corolla near throat; pistil 1, ovary inferior, 1-chambered, 1-seeded, style 1, branches 2, generally hair-tufted at tip, stigmas 2, generally on inside of style branches
Fruit: achene, cylindric to ovoid, generally deciduous with pappus attached
Genera in family: ± 1300 genera, 21,000 species (largest family of dicots): worldwide. Largest family in CA. Also see tribal key to CA genera: Strother 1997 Madroño 44(1):1–28. See glossary p. 25 for illustrations of general family characteristics.



James D. Morefield

Annual to subshrubs, generally ± hairy
Leaves alternate or basal, generally petioled, reduced upward, entire and linear or generally elliptic to ovate or obovate and 1–4-pinnately lobed; 1° lobes longest near middle or base of blade
Inflorescence: heads discoid (but outer flowers often enlarged, ± ray-like), 1–many per stem, generally in terminal cymes; peduncle generally hairy like phyllary bases; involucre generally < 15 mm diam, cylindric to obconic or hemispheric; phyllaries in 1–2 ± equal series, generally linear to lanceolate, tips generally ± flat, generally ± green; receptacle flat to rounded, generally naked
Flowers 10–many; corollas radial (outer, if enlarged, ± bilateral), generally white to pinkish or yellow, generally opening in daytime; anthers generally exserted
Fruit club-shaped, generally not compressed, stiffly hairy; pappus 0 or of 4–20 fringed scales in 1–few series
Species in genus: 18 species: w North America
Etymology: (Greek: gaping ray, from enlarged outer corollas of some)
Reference: [Mooring 1980 Amer J Bot 67:1304–1309]
Spp. of sect. Chaenactis hybridize.


C. douglasii (Hook.) Hook. & Arn.

Perennial, biennial(?), sometimes flowering first year
Stems 1–several, erect to spreading, < 50 cm, generally thinly grayish cobwebby; hairs thinning with age
Leaves < 15 cm, generally cobwebby to ± tomentose, not fleshy; basal rosette ± persistent; largest blades generally 2-pinnately lobed, 1° lobes 3–7 pairs, ± crowded, longest near middle, tips curled
Inflorescence: heads 1–many per stem; peduncles < 10 cm; involucre obconic to hemispheric, generally glandular-hairy; longest phyllaries 9–14 mm, tips generally erect, ± rigid, blunt
Flowers: corollas radial, 5–8 mm, white to pinkish, outer somewhat enlarged
Fruit 5–8 mm; pappus scales 8–20 in indistinct series, ± equal, longest generally 3–6 mm
Ecology: Dry, open often disturbed areas, alpine crevices
Elevation: 1000–3500 m.
Bioregional distribution: Northwestern California, Cascade Range, Sierra Nevada, Great Basin Floristic Province, n Desert Mountains
Distribution outside California: to British Columbia, Montana, Colorado, Arizona

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