TREATMENT FROM THE JEPSON MANUAL (1993) |
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©Copyright 1993 by the Regents of the University of California
For up-to-date information about California vascular plants, visit the Jepson eFlora. |
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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, 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 1several, generally barbed
Species in genus: ± 230 species: worldwide
Etymology: (Latin: 2 teeth)
Reference: [Sherff & Alexander 1955 North America Flora 2(2):70129]
Introduced |
Annual, glabrous
Stems erect, 415 dm
Leaves simple, petioled; blades < or = 20 cm, lanceolate, acuminate, serrate
Inflorescence: heads generally discoid, erect; peduncles 16 cm; involucre 720 mm diam (except leafy tips of outer phyllaries), hemispheric; outer phyllaries 45, generally 13 cm, ± linear, spreading; inner phyllaries 78 mm, ovate; chaff scales 810 mm, black or greenish with fine black lines
Ray flowers generally 0
Disk flowers: corollas ± 3 mm
Fruit wedge-shaped, ± flat; outer achenes 3.54 mm, 23-angled; inner achenes 58 mm, 4-angled; barbs of angles ascending below, reflexed above; pappus awns generally 4, 13.6 mm
Chromosomes: 2n=48, 72
Ecology: Freshwater wetlands
Elevation: 501600 m.
Bioregional distribution: c Sierra Nevada, San Joaquin Valley
Distribution outside California: native to e N.America, Europe
Synonyms: B. connata Muhlenb. var. petiolata (Nutt.) Farw