|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 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.
Annual 18 dm
Stem simple below, branched above
Leaves generally linear to narrowly elliptic, entire to sparsely dentate; lower 518 cm; upper entire, generally densely glandular; leaf clusters in upper axils generally 0
Inflorescence: heads solitary or in small groups, sessile to long-peduncled; involucre 3.512 mm; phyllaries long-soft-hairy and densely stalked-glandular; chaff scales scattered, fused at base, falling with disk flowers, tips blunt, ± hairy
Ray flowers 513; ligules 511 mm, generally white, generally red- or purple-striped below, central lobe narrow
Disk flowers 560, staminate; corollas white to yellow; anthers appearing black
Fruit 23 mm; beak 0; disk pappus 0
Ecology: Common. Grassland, fallow fields
Elevation: < 1400 m.
Bioregional distribution: North Coast Ranges, w&c Great Central Valley, Central Western California
Distribution outside California: sw Oregon
± interfertile races; intergradation compounded by seasonal changes in form.
See the CNPS Inventory for information about endangerment and rarity.
Stem ± soft-hairy and puberulent
Leaves: lower green, finely strigose to puberulent; upper generally glandless
Inflorescence open; heads peduncled; involucre 58 mm, phyllary tips generally < body
Ecology: UNCOMMON. Grassland, fallow fields
Elevation: < 1200 m.
Bioregional distribution: n&c North Coast Ranges
Synonyms: H. t. (Babc. & H.M. Hall) D.D. Keck