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 or branched
Leaves simple, basal and alternate, petioled or upper sessile; blades entire, toothed or pinnately lobed
Inflorescence: heads radiate or discoid, 1few, terminal; peduncles long, stout; involucre disk-shaped; phyllaries in 13 equal or unequal series, spreading or reflexed; receptacle conic to columnar, chaffy; chaff scales oblong, entire folded around fruits
Ray flowers 0 or many, sterile
Disk flowers many; corolla yellow to dark brown, diam of tube and throat ± equal; style tips blunt-triangular
Fruit oblong, 4-angled, ± flattened; pappus a crown of fused scales or 0
Species in genus: ± 15 species: North America
Etymology: (O.J. Rudbeck, 16301702, and O.O. Rudbeck, 16601740, professors of botany at Uppsala, Sweden)