TREATMENT FROM THE JEPSON MANUAL (1993) |
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©Copyright 1993 by the Regents of the University of California
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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 to perennial herb (sometimes short-lived, dying after flowering once)
Stem generally erect
Leaves: lower generally tapered or petioled, often wavy-margined, generally pinnately lobed, ± dentate, lobes and teeth spine-tipped, margin generally spiny-ciliate, glabrous to tomentose; upper generally sessile, ± reduced
Inflorescence: heads discoid, 1many; involucre cylindric to spheric; phyllaries many, graduated in several series, outer spine-tipped; receptacle flat, long-bristly
Flowers generally many; corollas ± bilateral, white to red or purple, tube long, slender, lobes linear; anther bases sharply sagittate, tips oblong; style tip with slightly swollen node, appendage (above node) long, cylindric, branches very short
Fruit ovoid, glabrous; scar slightly angled; pappus bristles many, plumose, ± persistent or falling in ring
Species in genus: ± 200 species: North America, Eurasia
Etymology: (Greek: thistle)
Taxa difficult, incompletely differentiated, hybridize.
Native |
Perennial (appearing biennial) 0.57(9) dm, compact, low, sometimes erect, taprooted from rootstock
Stem 1several, few-branched
Leaves loosely tomentose above, becoming green, ± glabrous, generally ± persistently gray-tomentose below; lower < 35 cm, petioles smooth or spiny, blades ± 13 X lobed, main spines 27 mm; middle and upper well developed
Inflorescence: heads 1several, ± clustered, often closely subtended by upper leaves; peduncles 03(12) cm; involucres 2.55 cm, 26 cm diam, hemispheric to widely bell-shaped, soon becoming glabrous; phyllaries strongly graduated in 510 series, generally tightly appressed, outer and middle ovate to lanceolate, generally rounded or obtuse, tipped by spines 12(5) mm, inner tips thin, flat
Flowers: corollas 2530 mm, white to purple, tube 1015 mm, throat 710 mm, lobes 58 mm
Fruit 56.5 mm, ± compressed, brown; pappus 2040 mm
Chromosomes: 2n=16
Ecology: Open places, grassland, woodland
Elevation: < 350 m.
Bioregional distribution: c&s North Coast, Outer North Coast Ranges, n&c Central Coast, San Francisco Bay Area, n Outer South Coast Ranges
Synonyms: var. walkerianum (Petr.) J.T. Howell; C. w. Petr.; var. xerolepis Petr