|Jepson Flora Project: Jepson Interchange|
|TREATMENT FROM THE JEPSON MANUAL (1993)||
previous taxon |
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.
Biennial 130 dm, erect or low, mound-like
Stem generally 1, branched above (near base in dwarf plants), ± tomentose
Leaves ± densely gray- or whitish tomentose, especially below; lower 14 dm, petioles spiny-winged, blade oblanceolate, lobed 1/2+ to midvein, lobes widely triangular, dentate or further lobed, main spines 110 mm; upper gradually reduced, sessile, ± clasping or short-decurrent, linear or oblong, often entire, often spinier than lower, uppermost bract-like
Inflorescence: heads 1several in loose to tight cluster (barely raised above rosette in dwarf plants); peduncles 130 cm; involucres 1.55 cm, 1.58 cm diam, ovoid to spheric; phyllaries ± equal to strongly graduated, linear or linear-lanceolate, straight, ascending and appressed to widely radiating, often connected side-to-side by conspicuous cobwebby hairs, spines 310+ mm, inner with tips flat, straight
Flowers: corollas 1840 mm, white to purple or red, tube 818 mm, throat 57 mm, lobes 510 mm
Fruit 56 mm, shiny, ± brown; pappus 1530 mm
Ecology: Many habitats
Elevation: < 3600 m.
Bioregional distribution: California Floristic Province (except San Joaquin Valley), Modoc Plateau, White and Inyo Mountains, w Mojave Desert
Distribution outside California: to s Oregon, sw Idaho, w Nevada
Variable; ± distinctive, intergrading races often treated as sp.