TREATMENT FROM THE JEPSON MANUAL (1993) |
previous taxon |
next taxon
Jepson Interchange (more information) |
|
©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, biennial, perennial herb
Stems erect, simple to much-branched
Leaves simple, basal or alternate, sessile or petioled, entire or divided 1 or more times into linear lobes, dotted with sunken resin glands
Inflorescence: heads generally radiate, solitary or in fewmany-headed cymes; involucre hemispheric; phyllaries in 23 similar or dissimilar series; receptacle flat to rounded, naked
Ray flowers fewmany; corolla yellow, fan-shaped, 35-lobed
Disk flowers many; corolla yellow
Fruit obpyramidal, generally 5-angled, hairy; pappus of ± 5 membranous, often awn-tipped scales
Species in genus: 28 species: w North America, South America
Etymology: (Greek: sharp membrane, from pappus)
Horticultural information: TRY.
Native |
Annual 1560 cm, soft-hairy, ± glabrous in age
Stems branched above
Leaves: basal generally 0 at time of flower; cauline 15 cm, divided into linear lobes 1 mm or less wide
Inflorescence: heads in flat-topped cyme; peduncles 215 cm; involucre generally 57 mm diam; outer phyllaries 35 mm, < inner phyllaries, thickened and fused at base
Ray flowers ± 8; ligules generally 1 cm or less, yellow, fading to cream and ± persistent on fruit
Disk flowers: corolla 34 mm
Fruit ± 2 mm; pappus scales 2 mm, lanceolate
Chromosomes: 2n=11,12,14,15
Ecology: Sandy flats near Colorado River
Elevation: < 150 m.
Bioregional distribution: e Sonoran Desert
Distribution outside California: to Utah, Texas, n Mexico
Flowering time: FebMay
TOXIC range plant outside CA .