TREATMENT FROM THE JEPSON MANUAL (1993) previous taxon | next taxon
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©Copyright 1993 by the Regents of the University of California
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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. laevis (L.) Britton, Sterns & Poggenb.


Annual, perennial herb, generally ± glabrous
Stems 2–25 dm, ± decumbent to erect, ± cylindric
Leaves simple, sessile; bases sometimes fused around stem; blades 5–15 cm, ± lanceolate, acute to acuminate, serrate
Inflorescence: heads radiate, erect in flower, often nodding in fruit; peduncle 2–10 cm; involucre 1–2 cm diam, bell-shaped; outer phyllaries 6–8, 1–2 mm, linear-lanceolate, sparsely ciliate; inner phyllaries 8–16 mm, obovate; chaff scales reddish tipped
Ray flowers 7–8; ligules 1.5–3 cm, yellow
Disk flowers: corollas 4–6 mm, yellow
Fruit narrowly wedge-shaped, flat or 3–4-angled; angles thin, barbed; pappus awns 2–4, 3–5 mm
Chromosomes: 2n=22
Ecology: Freshwater wetlands
Elevation: generally < 300 m.
Bioregional distribution: Great Central Valley, South Coast Ranges, Southwestern California, East of Sierra Nevada, Mojave Desert (Mojave River)
Distribution outside California: to e N.America
Flowering time: Aug–Nov
Much like B. cernua
Horticultural information: WET, SUN: 7, 8, 9, 10, 11, 12, 14, 15, 16, 18, 19, 20, 21, 22, 23, 24.

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