This page is based on the 1993 Jepson Manual.
Please see the Jepson eFlora for up-to-date information about California vascular plants.
|Jepson Flora Project: Jepson Interchange|
|TREATMENT FROM THE JEPSON MANUAL||
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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California
Print edition is available from the University of California Press
|The second edition of The Jepson Manual (2012) is available from the University of California Press|
|See also the Jepson eFlora, which parallels the Second Edition|
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.
Perennial 510 dm, dioecious; rootstock creeping; herbage green
Stem colonial, very leafy
Leaves 520 cm, mostly cauline, gradually reduced upward, sessile, tapered at base, sometimes decurrent as spiny wings, subentire to coarsely dentate or 12 X lobed; main spines 35 mm
Inflorescence: heads severalmany, cymes tight to ± open, rounded or flat-topped; peduncles 04 cm; involucre hemispheric to ovoid, 12 cm, 12 cm diam, generally ± purplish, ± tomentose when young; outer phyllaries ovate, tipped by spines ± 1 mm, inner lanceolate, tips flat, membranous
Flowers: corollas generally purplish, sometimes white or pink
Staminate flower: corollas 1213 mm, > pappus, tube 8 mm, throat 11.5 mm, lobes 34 mm
Pistillate flower: corollas 1420 mm, generally < pappus, tube 1016 mm, throat ± 1 mm, lobes 23 mm
Fruit 23 mm; pappus 1323 mm
Ecology: Disturbed places
Elevation: < 1800 m.
Bioregional distribution: California Floristic Province (except San Joaquin Valley, s Sierra Nevada), East of Sierra Nevada, w Mojave Desert
Distribution outside California: N.America.; native to Europe
Flowering time: JunSep
|YOU CAN HELP US make sure that our distributional information is correct and current. If you know that a plant occurs in a wild, reproducing state in a Jepson bioregion NOT highlighted on the map, please contact us with that information. Please realize that we cannot incorporate range extensions without access to a voucher specimen, which should (ultimately) be deposited in an herbarium. You can send the pressed, dried collection (with complete locality information indicated) to us (e-mail us for details) or refer us to an accessioned herbarium specimen. Non-occurrence of a plant in an indicated area is difficult to document, but we will especially value your input on those types of possible errors (see automatic conversion of distribution data to maps).|