TREATMENT FROM THE JEPSON MANUAL (1993) |
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©Copyright 1993 by the Regents of the University of California
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Annual to tree
Leaves basal or cauline, alternate to whorled, simple to compound
Inflorescence: 1° inflorescence a head, each resembling a flower, 1many, generally arrayed in cymes, generally subtended by ± calyx-like involucre; flowers 1many 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)45; stamens 45, 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):128. See glossary p. 25 for illustrations of general family characteristics.
Annual to subshrubs, generally ± hairy
Leaves alternate or basal, generally petioled, reduced upward, entire and linear or generally elliptic to ovate or obovate and 14-pinnately lobed; 1° lobes longest near middle or base of blade
Inflorescence: heads discoid (but outer flowers often enlarged, ± ray-like), 1many per stem, generally in terminal cymes; peduncle generally hairy like phyllary bases; involucre generally < 15 mm diam, cylindric to obconic or hemispheric; phyllaries in 12 ± equal series, generally linear to lanceolate, tips generally ± flat, generally ± green; receptacle flat to rounded, generally naked
Flowers 10many; 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 420 fringed scales in 1few 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 67:13041309]
Spp. of sect. Chaenactis hybridize.
Native |
Annual
Stems generally 1few, erect to spreading, < 50 cm; hairs thinning with age
Leaves < 11 cm, ± cobwebby, fleshy or not; largest entire or 12-pinnately lobed, 1° lobes 17 pairs, longest near blade middle, tips flat to curled or cylindric
Inflorescence: heads 1several per stem; peduncle < 20 cm; involucre widely cylindric to obconic or hemispheric, generally ± tomentose or glandular-hairy; longest phyllaries 4.59 mm, tips erect, ± rigid, generally blunt
Flowers: corollas ± bright to deep yellow, outer bilateral, greatly enlarged, inner radial, 48 mm
Fruit 39 mm; pappus scales (1)48 in 12 series, scales of outer fruit generally < inner, unequal, scales of inner fruit generally equal, longest 18 mm
Chromosomes: 2n=12
Ecology: Generally dry open places, sometimes dunes or serpentine
Elevation: < 1600 m.
Bioregional distribution: North Coast Ranges, Sierra Nevada Foothills, Tehachapi Mountain Area, Great Central Valley, Central Western California, Southwestern California, w edge Desert
Distribution outside California: n Baja California
Highly variable; some forms like C. stevioides except flower color.