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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.



G. Ledyard Stebbins

Annual to shrubs; sap milky
Stems erect, smooth, leafy
Leaves basal and cauline, alternate, ± entire to toothed and coarsely pinnate-lobed; cauline generally sessile, clasping
Inflorescence: heads ligulate, in cymes; involucre swollen at base; phyllaries generally in 3 series, outer many, short-triangular, those of inner 2 series linear, tapered; receptacle ± flat, naked
Flowers many; ligules yellow, readily withering
Fruit generally ± flat, beakless; pappus of many fine, white bristles
Species in genus: 54 species: Eurasia, Africa
Etymology: (Ancient Greek name)
Reference: [Boulos 1972–74 Bot Not 125:287–319, 126:155–196; 127:7–37,402–451]


S. tenerrimus L.

Annual to perennial herb 1–8 dm
Stems slender, generally much-branched
Leaves: basal generally < cauline, tapered to clasping bases; cauline 3–20 cm, sessile, clasping, basal clasping lobes acute; blades variously lobed, lobes linear to triangular, often secondarily lobed
Inflorescence: peduncles 0.5–8 cm, tomentose below heads; involucre 10–12 mm
Flowers: ligule ± 1/3 > tube
Fruit 2.5–3.3 mm, 1–3-ribbed on each face; ribs roughened; pappus bristles 6–8 mm
Chromosomes: 2n=14
Ecology: Uncommon. Weed of disturbed sites
Elevation: generally < 500 m.
Bioregional distribution: San Joaquin Valley, Channel Islands, Peninsular Ranges
Distribution outside California: native to s Europe

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