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.
Introduced |
Biennial 320 dm
Stem generally 1, ± openly branched above middle, loosely tomentose, often glandular-hairy
Leaves harshly bristly above, sometimes ± tomentose when young, ± tomentose below; main veins prominently raised on lower surface, ± glandular; lower 1040 cm, sessile or wing-petioled, shallowly to deeply 12 X lobed; cauline gradually reduced, long-decurrent as spiny wings, generally spinier than lower, main lobes generally rigidly spreading, spine-margined, otherwise entire, tip prolonged, main spines < 15 mm
Inflorescence: heads 1several, ± clustered, closely subtended by bract-like uppermost leaves; peduncles 16 cm; involucres 34 cm, 24 cm diam, hemispheric or bell-shaped; phyllaries graduated in 510 series, tips linear to linear-lanceolate, spreading to reflexed, spines 15 mm
Flowers: corollas 2535 mm, purple, tube 1825 mm, throat 56 mm, lobes 56 mm
Fruit 3.54.5 mm, light-brown or tan; pappus 2030 mm
Chromosomes: 2n=68
Ecology: Common. Disturbed areas
Elevation: < 2300 m.
Bioregional distribution: California Floristic Province, Great Basin Floristic Province
Distribution outside California: N.America; native to Europe
Flowering time: JunSep