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.--> |
AND IS MAINTAINED FOR ARCHIVAL PURPOSES ONLY |
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, perennial herb, ± tomentose throughout
Stems 1many from base
Leaves basal and alternate, simple, entire to deeply lobed, ± reduced upward, petioled or upper sessile, tomentose and glandular
Inflorescence: heads radiate, solitary or in few-headed cymes; peduncles short to very long; involucre cylindric to bell-shaped or hemispheric; phyllaries in 12 ± equal series, linear-lanceolate; receptacle flat to slightly rounded, naked or with scattered, narrow chaff
Ray flowers 4many; ligules ovate, 3-lobed, sessile on ovary, yellow, drying cream, papery, reflexed and persistent on fruit when dry
Disk flowers 8many; corollas yellow, gland-dotted, lobes triangular, long-hairy; anther tips triangular; style tips short-triangular
Fruit linear to club-shaped, cylindric or ± angled, short-rough hairy and gland-dotted to glabrous; pappus 0
Species in genus: 3 species: sw US, Mex
Etymology: (J.W. Bailey, Am microscopist, born 1811)
Reference: [Brown 1973 PhD dissertation, AZ State Univ]
Native |
Annual (rarely perennial herb), ± loosely tomentose
Stems 15 dm, generally branched above base
Leaves mostly cauline; basal soon withering; cauline leaves 414 cm, not markedly reduced upward, linear-oblong to lanceolate or oblanceolate, entire or divided into linear lobes
Inflorescence: heads 23 in cymes; peduncles 25 cm; involucre 46 mm diam, cylindric to bell-shaped; phyllaries 810, 46 mm
Ray flowers 48; ligules 410 mm, obovate, shallowly 3-lobed, pale yellow
Disk flowers 820; corolla 2.53 mm
Fruit 45 mm, narrowly club-shaped, evenly ribbed
Chromosomes: 2n=32
Ecology: Sandy desert soils, especially dunes
Elevation: < 1100 m.
Bioregional distribution: Desert
Distribution outside California: w Arizona, n Mexico
Flowering time: FebJun, Oct