Jepson Flora Project: Jepson Interchange    

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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California

  • Up-to-date information about California vascular plants is available from the Jepson eFlora.



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.



Willard W. Payne

Leaves alternate, petioled, generally ± lobed, ± hairy
Inflorescence: staminate heads in clusters, involucre 0, receptacle chaffy; pistillate heads 2-flowered, 2-beaked, spiny, bur-like; phyllaries 0 or minute; chaff scales many, spirally arrayed, fused below, free tips spiny, hooked
Staminate flowers many; corolla translucent; filaments fused, attached to corolla tube base, anthers free; ovary slender
Pistillate flowers generally 2 per head; corolla 0; style branches long
Fruit 2, enclosed in bur, germinating in successive years; pappus 0
Species in genus: 2 species: worldwide
Etymology: (Greek: yellow, from fruit-extract dye)

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