Atriplex argentea |
Atriplex graciliflora |
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maidenhair spleenwort, silver orach, silver orache, silver saltbush, silverscale, silverscale orache, silverscale saltbush, silvery orache |
Blue Valley orach, slenderflower saltbush |
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Habit | Herbs, simple or freely branched, 0.5–6 dm; branches rather stout, angled, scurfy when young. | Herbs, branching from base, mainly 1–3 dm. | ||||||||||||||||
Stems | often suffused with red-purple, terete, sparingly farinose when young. |
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Leaves | often opposite proximally, petiolate or distal bracteate ones subsessile, blade lance-ovate, lanceolate, deltoid, or cordate, 5–75 × 4–50(–75) mm, base subhastate or obtuse to acute, margin entire or essentially so, sometimes closely repand-dentate, apex obtuse to acute or rounded, scurfy (glabrous). |
mainly alternate, numerous; petiole 2–12(–16) mm; blade cordate-ovate to orbicular, subreniform, cordate, or deltoid, (5–)8–20(–25) mm and about as wide or wider, base truncate to cordate (or attenuate when young), apex rounded to obtuse or acute. |
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Flowers | in axillary glomerules and terminal, interrupted spikes. |
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Staminate flowers | borne in distal axils, or in short dense spikes or panicles, or intermixed with pistillate, with 4–5-parted calyx. |
in loose, deciduous, terminal panicles overtopping foliage, rachis and branches filiform, glomerules often beadlike in alternate position along rachis, perianth 5-lobed. |
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Pistillate flowers | axillary. |
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Seeds | brown, 1.5–2 mm wide; radicle superior or lateral. |
white, 3 mm wide, dull. |
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Fruiting | bracteoles sessile, subsessile, or stipitate (stipe 0.5–5 mm), cuneate-orbicular, (2.5–)4–11.2 × 2–8.8(–14) mm, margin foliaceous below apex, subentire or dentate to laciniate, face smooth, tuberculate, or crested, processes sometimes again toothed, teeth then aligned with axis of process. |
bracteoles on stipes 2–6 mm, samaralike, suborbicular, oblong or cordate in outline, winged, compressed, 6–16 mm wide, margins 2–4 times as wide as body, wings undulate or entire, surfaces smooth. |
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2n | = 18, 36, 54. |
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Atriplex argentea |
Atriplex graciliflora |
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Phenology | Flowering summer. | |||||||||||||||||
Habitat | Saltbush, mat-atriplex, seepweed, greasewood, rabbitbrush, and tamarix communities on saline, often salt encrusted and semibarren substrates derived from Mancos Shale, Tropic Shale, Entrada, and other fine-textured formations | |||||||||||||||||
Elevation | 1100-2000 m (3600-6600 ft) | |||||||||||||||||
Distribution |
AZ; CA; CO; ID; KS; MT; ND; NE; NM; NV; OK; OR; SD; TX; UT; WA; WY; AB; BC; MB; SK; Mexico
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CO; UT |
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Discussion | Varieties 5 (5 in the flora). Herbarium materials have tended to represent a catchall for annual specimens not readily assignable to other taxa. Indeed, the distinguishing features of the Atriplex argentea complex are shared singly and often in combination with other taxa. Only by use of combinations of features can this taxon be defined. Those features, with much variation, center around the broad, typically ovate to deltoid leaf blades (often definitely 3-veined) and more-or-less compressed, sessile to subsessile (or short stipitate), fruiting bracteoles on which the marginal processes, or teeth, are mainly aligned with the plane compression, and with the faces quite smooth to variously appendaged. Still some specimens are apparently intermediate with other species, especially with the closely allied A. saccaria, with which it is at least partially sympatric. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Atriplex graciliflora is unique among our indigenous atriplices in having samaralike, entire fruiting bracteoles. When the bracteoles are considered along with the slender, terminal, staminate panicles of alternating beadlike glomerules, the species is unmatched. Its relationship is apparently with A. saccaria, which has undergone considerable morphologic radiation within the Four Corners region. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 4. | FNA vol. 4, p. 346. | ||||||||||||||||
Parent taxa | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Argenteae | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Graciliflorae | ||||||||||||||||
Sibling taxa | ||||||||||||||||||
Subordinate taxa | ||||||||||||||||||
Synonyms | Obione argentea | Obione graciliflora | ||||||||||||||||
Name authority | Nuttall: Gen. N. Amer. Pl. 1: 198. (1818) | M. E. Jones: Proc. Cali f. Acad. Sci., ser. 2, 5: 717. (1895) | ||||||||||||||||
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