TREATMENT FROM THE JEPSON MANUAL (1993) |
previous taxon |
next taxon
Jepson Interchange (more information) |
|
©Copyright 1993 by the Regents of the University of California
For up-to-date information about California vascular plants, visit the Jepson eFlora. |
AND IS MAINTAINED FOR ARCHIVAL PURPOSES ONLY |
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 |
Subshrub, branched below middle
Stems several, erect, 1060 cm; hairs near base dense, felt-like, white, persistent
Leaves < 9 cm, tomentose, not fleshy; basal rosette 0 or withering; largest blades 12-pinnately lobed, lobes 25 pairs, ± well separated, longest near base, tips flat
Inflorescence: heads 1few per stem; peduncles 515 cm; involucre cylindric, strongly glandular-hairy, not or scarcely tomentose; longest phyllaries 1417 mm, tips generally erect, ± rigid, generally blunt
Flowers: corollas white to pinkish, all radial, 8.510 mm, ± equal
Fruit 79 mm; pappus scales 1016 in indistinct series, ± equal, longest 79 mm
Chromosomes: 2n=12
Ecology: Dry, open areas
Elevation: 8002100 m.
Bioregional distribution: Klamath Ranges, Cascade Range
Horticultural information: In cultivation.