Jepson Flora Project: Jepson Interchange |
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TREATMENT FROM THE JEPSON MANUAL (1993) |
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Jepson Interchange (more information) |
©Copyright 1993 by the Regents of the University of California
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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.
Perennial, often matted, dioecious; staminate plants generally present
Leaves alternate, entire, generally ± tomentose
Inflorescence: heads discoid or disciform, 1 or in cyme-like clusters; phyllaries many in several series, papery or membranous (staminate wider, more conspicuous); receptacle naked
Staminate flowers 25 mm; corollas white, yellow, or red; pappus bristle tips generally enlarged
Pistillate flowers 210 mm; corollas barely lobed, white, yellow or red
Fruit 0.53.5 mm, ± elliptic; pappus bristles many, soft, weakly barbed
Species in genus: ± 40 species: Am, n Eurasia
Etymology: (Latin: antenna)
Reference: [Bayer 1990 Can J Bot 68:13891397 and Madroño 37:171183]
Many races reproduce by asexual seeds, their populations entirely pistillate plants.
Native |
Stems 513 cm; stolons many, matted
Leaves: basal 619 mm, ± linear to spoon-shaped, 1-veined, densely woolly; cauline 520 mm, linear
Inflorescence: heads 27; involucres 48 mm, base woolly; phyllaries narrow and acute (pistillate) or wide and blunt (staminate), upper part dark brownish black
Staminate flowers: corollas 2.84.5 mm
Pistillate flowers: corollas 34.5 mm
Fruit 0.61.6 mm, papillate or smooth; pappus 45.5 mm
Chromosomes: 2n=56,98,112
Ecology: High meadows, snow basins, ridges
Elevation: 18003900 m.
Bioregional distribution: Klamath Ranges, High North Coast Ranges, High Cascade Range, High Sierra Nevada, San Bernardino Mountains, White and Inyo Mountains
Distribution outside California: to sw Canada, Montana, Colorado, New Mexico
Flowering time: JulAug
Synonyms: A. alpina (L.) Gaertn. var. m. (Greene) JepsHorticultural information: DRN, IRR, SUN: 1, 2, 3, 7, 14, 15, 16, 17; DFCLT.