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. |
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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 |
Annual or biennial 13 m
Stem generally 1, generally simple below, openly branched above, thinly cobwebby, soft-hairy (hairs jointed), at least below; base < 10 cm diam, hollow
Leaves thinly cobwebby-tomentose above, gray-tomentose below, sometimes midvein with jointed hairs; lower 1.57 dm, petioles spiny-lobed, winged, blades elliptic to widely oblanceolate, 12 X lobed, lobes sometimes dentate, main spines 38 mm; middle and upper smaller, narrower, sessile, spiny-margined, bases wide-clasping; upper much reduced, generally very spiny, spines < ± 10 mm
Inflorescence: heads in loose to crowded cymes (sometimes on short axillary branches), closely subtended by uppermost leaves; peduncles 015 cm; involucres 1.53 cm, 1.53 cm diam, ovoid to ± bell-shaped, ± glabrous; phyllaries ± linear, at least outer irregularly spiny-fringed, outer and middle ascending or ± spreading, spines 35 mm, inner with tips erect, ± twisted
Flowers: corollas 1926 mm, pale rose-purple (white), tube 912 mm, throat 46 mm, lobes 59 mm
Fruit 55.5 mm, dark brown, ± compressed; pappus 1.52 cm
Chromosomes: 2n=32
Ecology: Freshwater marshes
Elevation: < 100 m.
Bioregional distribution: San Joaquin Valley.