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. fremontii A. Gray


Annual, branched below middle, sometimes ± scapose
Stems 1–many, ± erect, < 40 cm, becoming glabrous before flower time except near heads
Leaves < 9 cm, generally glabrous, ± fleshy; basal rosette withering; largest blades entire or 1-pinnately lobed, lobes 1–2(5) pairs, well separated, longest near middle, tips cylindric
Inflorescence: heads 1–few per stem; peduncles < 11 cm, generally glandular-hairy near heads; involucre obconic to hemispheric, ± truncate at base, becoming glabrous; longest phyllaries 8–10(12) mm, tips erect, rigid, sharp
Flowers: corollas white to pinkish, outer bilateral, greatly enlarged, inner radial, 5–7 mm
Fruit (3)6–8 mm; pappus scales in 1 series, smaller and unequal on outer fruit, on inner fruit 4(5), equal, longest generally 6–8.5 mm, > buds, tips visible
Chromosomes: 2n=10
Ecology: Open sand or gravel
Elevation: < 1600 m.
Bioregional distribution: Tehachapi Mountain Area, s San Joaquin Valley, Inner South Coast Ranges, more common in s East of Sierra Nevada, Desert
Distribution outside California: to sw Utah, w Arizona, n Baja California
Flowering time: Spring
Horticultural information: TRY.

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bioregional map for CHAENACTIS%20fremontii being generated

Retrieve Jepson Interchange Index to Plant Names entry for Chaenactis fremontii
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