|Jepson Flora Project: Jepson Interchange|
|TREATMENT FROM THE JEPSON MANUAL (1993)||
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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California
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, 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.
Annual or biennial 13 mSee the CNPS Inventory for information about endangerment and rarity.
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
Ecology: Freshwater marshes
Elevation: < 100 m.
Bioregional distribution: San Joaquin Valley.