| 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, 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.
Perennial; sap milky; herbage generally long-hairy
Stems erect, 1–10 dm
Leaves basal or cauline, alternate
Inflorescence: heads ligulate, few–many in cymes or panicles; involucre cylindric; phyllaries in 2–4 series of different lengths; receptacle naked
Flowers few–many; ligules yellow, white, or orange, readily withering
Fruit cylindric, slender; pappus of many slender bristles, brittle, dull white, tawny, or brownish
Species in genus: ± 250 species: ± worldwide
Etymology: (Greek: hawk)
Many reproduce only by asexual seeds.
| Introduced |
Stolons and leaf rosettes many
Stems 2–7 dm, densely hairy
Leaves all or mostly basal, 0.5–2 dm, oblanceolate to narrowly elliptic, entire or obscurely toothed, densely soft-hairy
Inflorescence scapose; heads in dense to loose cymes; involucres 5–9 mm; phyllaries glandular and black-hairy
Flowers 32–45; ligules orange-red, often drying ± purple
Fruit 1.5–2 mm; pappus white
Chromosomes: 2n=30,36,45,54
Ecology: Invasive weed of lawns, disturbed places
Elevation: ± 300 m.
Bioregional distribution: n Sierra Nevada Foothills (Grass Valley, Nevada Co.), expected more widely
Distribution outside California: native to Europe; noxious weed in ne US