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 to tree-like, generally ± loosely hairy, becoming ± subglabrous; roots generally fibrous, branched
Stems generally 1few per rosette
Leaves alternate; lower generally petioled; middle generally weakly clasping; uppermost generally bract-like
Inflorescence often ± flat-topped; heads radiate or discoid, 1many; involucre cylindric to hemispheric; main phyllaries in 1 equal series (often subtended by few, much-reduced outer phyllaries)
Ray flowers 013; ligules generally yellow to orange
Disk flowers generally < 40; corolla generally ± yellow; style tips truncate to obtuse, generally hair-tufted
Fruit cylindric; ribs shallow, often stiff-hairy; pappus of thin, minutely barbed deciduous bristles ± = fruit body
Species in genus: ± 1500 species: worldwide; some cultivated, some of unusual form
Recent taxonomic note: *For revised taxonomy of Senecio, see Barkley 1999 Sida 18(3):661672.
Etymology: (Latin: old man, from white pappus)
Reference: [Barkley 1978 North America Flora II 10:50139]
Among largest genera of flowering plants.
Introduced |
Annual 36 dm, from taproot, branched upward, sticky
Leaves 38 cm; lower, oblong, deeply toothed or lobed; petiole bases expanded
Inflorescence: heads radiate, many; main phyllaries < 10 mm, tips black
Ray flowers ± 13; ligules 1015 mm, (red-)purple
Disk flowers < 40; corolla yellowish
Fruit ribbed, glabrous
Chromosomes: 2n=20
Ecology: Uncommon. Disturbed coastal habitats
Elevation: < 100 m.
Bioregional distribution: Central Coast, San Francisco Bay Area, South Coast
Distribution outside California: native to s Africa
cultivated as ornamental.