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.

GUIZOTIA

Annual, perennial herb
Stems erect
Leaves simple; lower opposite; upper sometimes alternate, sessile
Inflorescence: heads radiate, borne in a terminal, leafy-bracted cyme; peduncles slender; involucre bell-shaped; phyllaries few, outer ± leaf-like in texture, inner membranous; receptacle conic, chaffy; chaff scales flat
Ray flowers few; corollas yellow; ligules wide, conspicuously 3-lobed
Disk flowers many; corollas yellow; style tips tapering
Fruit 4-angled, ± flattened, glabrous, shining; pappus 0
Species in genus: 6 species: Africa
Etymology: (Pierre Guizot, 1787–1874; French politician, historian)