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.



Annual, perennial herb, shrubs
Stems prostrate to erect
Leaves simple or pinnate, generally opposite, sessile or petioled
Inflorescence: heads radiate or discoid, generally few in CA; involucre cylindric to bell-shaped; phyllaries in 2 dissimilar series, outer generally ± leaf-like in texture, inner thinner, with transparent or scarious margins; receptacle chaffy; chaff scales narrow, flat
Ray flowers 0 or few; ligules yellow or white
Disk flowers generally many; corollas yellow, radial (or outermost white, bilateral)
Fruit narrowly club-shaped, thick or compressed front-to-back; pappus 0 or awns 1–several, generally barbed
Species in genus: ± 230 species: worldwide
Etymology: (Latin: 2 teeth)
Reference: [Sherff & Alexander 1955 North America Flora 2(2):70–129]


B. frondosa L.


Annual, ± glabrous
Stems 5–12 dm, square
Leaves compound, petioled; leaflets 2–8 cm, lanceolate, generally acuminate, serrate
Inflorescence: heads radiate or discoid, erect; peduncles 2–10 cm; involucre ± 1 cm diam, hemispheric; outer phyllaries 5–8, 1–5 cm, ± linear, ciliate; inner phyllaries 5–7 mm, ovate; chaff scales 5–7 mm, brownish
Ray flowers 0–few; corollas 2–3.5 mm
Disk flowers: corollas ± 2 mm, orange
Fruit 6–10 mm, blackish, narrowly wedge-shaped, flat, ± glabrous to stiffly hairy; pappus awns generally 2, 3–4.5 mm
Chromosomes: 2n=48
Ecology: Uncommon. Damp soil, especially disturbed sites
Elevation: generally < 1600 m.
Bioregional distribution: North Coast Ranges, Great Central Valley, Southwestern California, Great Basin Floristic Province
Distribution outside California: to e N.America
Flowering time: Aug–Oct

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