Jepson Interchange (more information)
Print edition is available from the University of California Press
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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 |
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TREATMENT FROM THE JEPSON MANUAL |
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Jepson Interchange (more information) |
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©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, 1–many, generally arrayed in cymes, generally subtended by ± calyx-like involucre; flowers 1–many 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)4–5; stamens 4–5, 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):1–28. See glossary p. 25 for illustrations of general family characteristics.
Species in genus: 1 sp
Etymology: (Greek: double pappus)
Reference: [Porter 1943 Amer J Bot 30:481–483]
| Native |
Shrub, glabrous
Stems much-branched, widely spreading to ascending, generally < 6 dm, striate, smooth, white above, grayish below; leafless stems spiny
Leaves short-petioled, generally < 2 cm, obovate or elliptic, entire, sometimes ± thick, light yellow- or gray-green
Inflorescence: heads radiate, in crowded, flat-topped clusters generally 3–5 cm wide; involucres cylindric, ± 5 mm, < 3 mm wide; phyllaries 7–12, ovate, whitish or pale green
Ray flowers 1–2, barely > involucre, tips 2- or 3-toothed, yellow
Disk flowers 3–7, staminate; corollas narrowly funnel-shaped, sinuses deep, lobes reflexed, style-branch appendages lanceolate to rounded
Fruit of ray flowers < or = 3 mm, hairy; pappus of 15–20 stout bristles fused at base, generally 1 mm; ovary of disk flowers < or = 1 mm, glabrous; pappus of 25 flattened, twisted bristles generally < or = 3 mm
Chromosomes: 2n=18
Ecology: Rocky or gravelly flats, slopes, canyons
Elevation: < 1600 m.
Bioregional distribution: c&e Mojave Desert
Distribution outside California: to Utah, Nevada, Arizona
Varieties not known to intergrade.
| Native |
Leaves minutely scabrous on surfaces and margins
Ecology:Habitats of sp.
Bioregional distribution: east-central Mojave Desert
Distribution outside California: to Utah, Nevada, Arizona
Synonyms: subsp. s. (A. Nelson) D.D. KeckHorticultural information: TRY.
| 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). |
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