Atriplex argentea |
Atriplex pusilla |
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maidenhair spleenwort, silver orach, silver orache, silver saltbush, silverscale, silverscale orache, silverscale saltbush, silvery orache |
dwarf orach, dwarf orache, small scale, smooth saltbush |
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Habit | Herbs, simple or freely branched, 0.5–6 dm; branches rather stout, angled, scurfy when young. | Herbs, freely branched, 0.5–2.5 dm; branches spreading to erect, typically suffused with red, slender, sparsely scurfy. | ||||||||||||||||
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). |
alternate except proximally, not especially numerous; blade elliptic to subelliptic or ovate, 2–12 × 3–6 mm, base acute, rounded, or subcordate, margin entire, gray to almost green scurfy. |
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Flowers | in axillary glomerules and terminal, interrupted spikes. |
solitary or paired in axils, staminate near branch ends, calyx 5-cleft. |
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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. |
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Seeds | brown, 1.5–2 mm wide; radicle superior or lateral. |
brownish, 0.8–1 mm. |
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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 simulating tiny bracteate leaves, sessile, ovate, compressed, 1–2 × 1 mm, united to apex, abruptly acute to acuminate, entire, faces plane. |
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2n | = 18, 36, 54. |
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Atriplex argentea |
Atriplex pusilla |
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Phenology | Flowering Jun–Oct. | |||||||||||||||||
Habitat | Saline substrates in valley bottoms, playas, and along drainages with greasewood, rabbitbrush, shadscale, and sagebrush | |||||||||||||||||
Elevation | 1000-2100 m (3300-6900 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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CA; NV; OR |
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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 pusilla is closely similar to, and possibly a near ally of, the geographically disjunct A. parishii complex of the Great Valley of California, which it simulates in all main features. The very tiny fruiting bracteoles, very difficult to discern among the distal bracteate leaves, are characteristic and apparently closely similar only to those of A. parishii var. minuscula. The red stems are almost universal in plants of this species. (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. 356. | ||||||||||||||||
Parent taxa | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Argenteae | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Pusillae | ||||||||||||||||
Sibling taxa | ||||||||||||||||||
Subordinate taxa | ||||||||||||||||||
Synonyms | Obione argentea | Obione pusilla | ||||||||||||||||
Name authority | Nuttall: Gen. N. Amer. Pl. 1: 198. (1818) | (Torrey) S. Watson: Proc. Amer. Acad. Arts 9: 110. (1874) | ||||||||||||||||
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