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.

ENCELIA

Curtis Clark

Shrubs
Stems generally many from base
Leaves alternate, generally drought-deciduous, simple, petioled, entire or rarely toothed
Inflorescence: heads radiate or discoid, solitary or in cyme-like panicles; peduncles generally long; involucre hemispheric; phyllaries in 2–3 series, free; receptacle chaffy, scales folded around fruits and falling with them
Ray flowers sterile; style 0; ligules yellow
Disk flowers many; corollas yellow or brown-purple, tube slender, throat abruptly expanded, lobes triangular; anther tips ovate, ± acute; style tips triangular
Fruit strongly compressed, obovate or wedge-shaped; edges long-ciliate; faces glabrous or short-hairy; pappus of 2 narrow scales or 0
Species in genus: 13 species: w North America, w South America
Etymology: (Christopher Encel, 16th century)
Commonly hybridizing, especially in disturbed areas; E. farinosa X E. frutescens is common; E. farinosa X E. californica, E. farinosa X E. actoni, E. actoni X E. frutescens, E. frutescens X E. virginensis, E. farinosa X Geraea canescens have been reported.

Native

E. farinosa Torr. & A. Gray

BRITTLEBUSH, INCIENSO

Shrub 3–15 dm, from 1 or several trunks; sap fragrant
Stems much-branched above; young stems tomentose; older stems with smooth bark
Leaves clustered near stem tips; petioles 10–20 mm; blades 2–7 cm, ovate to lanceolate, obtuse or acute, silver- or gray-tomentose
Inflorescence: heads radiate, 3–9 in panicles; peduncles ± yellow, glabrous except just below heads; involucre 4–10 mm; phyllaries lanceolate
Ray flowers 11–21; ligules 8–12 mm
Disk flowers: corollas 5–6 mm, yellow or brown-purple
Fruit 3–6 mm; pappus 0
Chromosomes: 2n=36
Ecology: Coastal scrub, stony desert hillsides
Elevation: < 1000 m.
Bioregional distribution: e South Coast and adjacent Peninsular Ranges, Desert
Distribution outside California: to sw Utah, Arizona, nw Mexico
Flowering time: Mar–May
Dried resin used as incense
Synonyms: var. phenicodonta (S.F. Blake) I.M. Johnst
Horticultural information: SUN, DRN: 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 19, 20, 21, 22, 23, 24.