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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.

CHRYSOTHAMNUS

RABBITBRUSH

Loran C. Anderson

Perennial to shrub
Stems erect, often densely clustered
Leaves alternate, sessile, entire
Inflorescence: heads discoid, arrayed in ± dense cymes, peduncled or subsessile; involucre generally cylindric; phyllaries generally in 3–5 series (± 5 vertical ranks), free, overlapping, keeled; receptacle naked
Flowers 2–20 (often 5) per head; corollas generally yellow, lobes 0.5–3 mm, generally spreading; style branches long, slender, generally exserted
Fruit narrowly cylindric, ± 5-ridged, generally light brown; pappus of many white to brownish bristles
Species in genus: 16 species: sw Can to n Mex
Etymology: (Greek: golden shrub)
Closely related to (perhaps part of) Ericameria.

Native

C. nauseosus (Pall.) Britton

RUBBER RABBITBRUSH

Shrub < 28 dm, ± tomentose; odor strong
Stems whitish to green, ± flexible, very leafy or naked at flower
Leaves 1–7 cm, thread-like to narrowly (ob)lanceolate
Inflorescence dense, flat-topped or rounded, panicle-like; involucre 6–14.5 mm, cylindric; phyllaries ± lanceolate to ovate, in vertical ranks, ± strongly keeled, firm, obtuse to acute
Flowers generally 5; corollas 6–12 mm; style appendage generally > stigma
Fruit 3–8 mm, generally hairy; pappus generally = corolla
Chromosomes: 2n=18
Ecology: Diverse habitats
Elevation: 50–3300 m.
Bioregional distribution: Northwestern California, Cascade Range, Sierra Nevada, Central Western California (except Central Coast), Transverse Ranges, Peninsular Ranges, Great Basin Floristic Province, Mojave Desert
Distribution outside California: to British Columbia, Montana, Wyoming, Colorado, New Mexico, Baja California
Highly variable; 22 subspp. in w US.

Native

subsp. washoensis L. Anderson

Plant 3–10 dm
Stems generally whitish
Leaves ± 3 cm, ± narrowly oblanceolate
Inflorescence: involucre 10–12 mm, sparsely long-hairy and short-tomentose
Flowers: corollas 7.5–9 mm, lobes nearly erect, sparsely long-hairy
Fruit glabrous except white hair-tuft near top
Ecology: Uncommon. Dry juniper or pinyon grassland
Elevation: 1500–1700 m.
Bioregional distribution: Modoc Plateau
Distribution outside California: nw Nevada