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	©Copyright 1993 by the Regents of the University of California Print edition is available from the University of California Press

	The second edition of The Jepson Manual (2012) is available from the University of California Press
	See also the Jepson eFlora, which parallels the Second Edition

ASTERACEAE

SUNFLOWER FAMILY

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.

ASTER

ASTER

Geraldine A. Allen

Annual or perennial herb from caudex or rhizome
Stem generally erect, 1–20 dm
Leaves basal, cauline, or both, alternate, generally entire; basal generally petioled
Inflorescence: heads generally radiate, solitary or in a cyme or panicle; involucre obconic to hemispheric; phyllaries in 2–6 series, outer generally < inner, free, at least inner with pale, papery margins; receptacle ± flat, naked
Ray flowers 0–many; corolla violet to pink or white
Disk flowers many; corolla and anthers generally yellow, tube generally < throat; anther tips ± triangular; style branches flat on inner face, base ± warty, tip acute, hairy
Fruit generally rounded, ± ribbed, ± brown; pappus of bristles, white to brownish
Species in genus: ± 250 species: North America, Eurasia, Africa
Etymology: (Greek: star)
Reference: [Allen 1984 Syst Bot 9:175–191]
Recent taxonomic note: *See also revised taxonomy of Nesom 1994 Phytologia 77:141–297.

Native

A. occidentalis (Nutt.) Torr. & A. Gray

Perennial; rhizomes long
Stems 2–8 dm, glabrous to ± hairy
Leaves basal and cauline, 5–15 cm, ± smaller upward, ± linear to narrowly elliptic, acute, ± entire, ± glabrous
Inflorescence: heads in an open cyme; phyllaries linear to oblong, acute or outer ± obtuse, green at tip, ± pale-margined at base
Ray flowers many; corollas 8–12 mm, violet
Fruit hairy
Chromosomes: 2n=16,32, 48,64
Ecology: Meadows
Elevation: 1200–2800 m.
Bioregional distribution: Northwestern California, Cascade Range, Sierra Nevada, Transverse Ranges, San Jacinto Mountains, Great Basin Floristic Province
Distribution outside California: to British Columbia, Colorado, Baja California
Variable.

Native

var. yosemitanus (A. Gray) Cronquist

WESTERN BOG ASTER

Stems 3–8 dm
Leaves ± linear
Chromosomes: 2n=16,32
Ecology: UNCOMMON. Meadows
Elevation: 1200–2100 m.
Bioregional distribution: Klamath Ranges, Cascade Range, Sierra Nevada
Distribution outside California: s Oregon
Synonyms: A. paludicola Piper
Recent taxonomic note: *Symphyotrichum spathulatum (Lindl.) G.L. Nesom var. yosemitanum (A. Gray) G.L. Nesom, in part.