TREATMENT FROM THE JEPSON MANUAL (1993) |
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©Copyright 1993 by the Regents of the University of California
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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 shrub, generally glandular, aromatic
Stems generally branched above middle or throughout
Leaves generally cauline (some also basal and cauline), generally alternate, generally linear to (ob)lanceolate, entire to pinnately lobed, generally not spine-tipped; lower generally toothed to lobed; upper generally entire
Inflorescence: heads radiate, generally 1many in open cymes; involucre generally hemispheric; phyllaries generally linear to lanceolate, half-enclosing ray fruits; chaff scales generally in 1 ring between ray and disk flowers (scattered)
Ray flowers 3many; ligules generally 3-lobed, white to yellow
Disk flowers 3many, staminate or fruiting; corollas white to yellow, becoming red; anther tips ovate; style branches long, tips bristly
Fruit: ray achenes ± 3-angled; pappus 0; disk achenes cylindric or obconic, pappus 0 or scales generally linear to lanceolate
Species in genus: ± 25 species: CA, OR, w AZ, n Baja CA
Etymology: (Greek: half girdle, from sheathing phyllaries)
Reference: [Tanowitz 1982 Syst Bot 7:314339; Venkatesh 1958 Amer J Bot 45:7784]
Recent taxonomic note: *See revised taxonomy of Baldwin 1999 Novon 9:462471.
Native |
Annual 112 dm
Stems: branches generally stiff, bristly
Leaves: lower 515 cm, linear-lanceolate, deeply 2 X divided; upper linear, spine-tipped, glabrous to scabrous, margin stiff-ciliate, generally with axillary leaf clusters
Inflorescence sometimes dense; heads ± clustered; involucre 36 mm, generally overtopped by upper leaves; phyllaries keeled, spine-tipped, scabrous; chaff scales scattered, generally spine-tipped
Ray flowers many; ligule 35 mm, 2-lobed, yellow
Disk flowers many, generally staminate; corollas and anthers yellow
Fruit ± 2 mm, beaked; disk pappus 0
Chromosomes: 2n=18
Ecology: Grassland, depressions, marshes
Elevation: < 500 m.
Bioregional distribution: s North Coast Ranges, Cascade Range Foothills, Great Central Valley, n Central Coast, San Francisco Bay Area, South Coast Ranges, alien in Southwestern California
Distribution outside California: to Washington
Recent taxonomic note: *Centromadia pungens (Hook. & Arn.) Greene
Native |
Plant generally erect, 510 dm
Stems loosely branched
Leaves and bracts not scabrous
Inflorescence: heads generally 46 mm diam, scattered
Ecology: Grassland
Elevation: < 500 m.
Bioregional distribution: Cascade Range Foothills, Sacramento Valley
Distribution outside California: to Washington
Recent taxonomic note: *Centromadia pungens (Hook. & Arn.) Greene subsp. septentrionalis (D.D. Keck) B.G. Baldwin