Atriplex truncata |
Atriplex covillei |
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truncate saltbrush, wedge orach, wedge orache, wedgeleaf orache, wedgescale, wedgescale orache, wedgescale saltbush |
Coville's orach |
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Habit | Herbs, typically erect. | Herbs, spreading, 1–4(–5) dm and as broad. |
Stems | simple or more commonly branched throughout, mainly 2–8(–10) dm, branches mostly obtusely angled; herbage scurfy, becoming glabrate. |
terete, sparsely scurfy when young. |
Leaves | alternate or proximalmost opposite, short petiolate proximally, sessile and often cordate-clasping distally; blade ovate to deltoid or oval, 4–30(–40) × 3–30 mm, base truncate or subhastate to rounded, margin entire or dentate, apex acute to obtuse. |
petiole to 1/2 as long as blade (becoming subsessile distally); blade green or finally stramineous, (10–)20–50 × 6–30 mm, firm, base abruptly acute to narrowly cuneate, apex acute to attenuate, sparsely scurfy. |
Flowers | in axillary glomerules. |
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Staminate flowers | in glomerules mainly in distal axils; sepals 3–5. |
in sessile glomerules in distal axils, often mixed with pistillate ones, staminate calyx deeply 5-cleft; lobes obtuse, not appendaged. |
Pistillate flowers | with calyx of (1–)3(–5) hyaline sepals. |
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Seeds | brown, 1–2 mm wide. |
dark reddish brown, 1–1.5 mm. |
Fruiting | bracteoles scarcely compressed, 2–3 mm and as wide, apex truncate to broadly rounded, with 3 (or more) teeth across summit, surfaces smooth (or rarely tuberculate). |
bracteoles sessile or stipitate, 6–12 × 4–7 mm, margin mostly 3-lobed, with elongate terminal lobe triangular to lanceolate, 2 short rounded lobes at base or sides merely rounded at base, united to beyond middle. |
2n | = 18. |
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Atriplex truncata |
Atriplex covillei |
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Phenology | Flowering summer–fall. | Flowering summer–fall. |
Habitat | Saline saltgrass-greasewood-rabbitbrush communities, and other pans or palustrine or lacustrine habitats | Mixed saltbush-greasewood, rabbitbrush, warm desert shrub, and salt grass communities in saline substrates |
Elevation | 400-2700 m (1300-8900 ft) | 800-1700 m (2600-5600 ft) |
Distribution |
CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC; SK
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CA; NV; OR |
Discussion | Endolepis covillei was treated within the synonymy of Atriplex phyllostegia (Torrey) S. Watson by H. M. Hall and F. E. Clements (1923). H. C. Stutz et al. (1993) placed Atriplex covillei within Endolepis, based in large part on the presence of a perianth subtending the pistil within the fruiting bracteoles and on the lack of Kranz anatomy in the leaves. The pattern of venation is, nevertheless, very similar to that in species with Kranz anatomy. The presence of perianth scales in the pistillate flowers of A. covillei has been regarded as evidence of relationship with A. suckleyi. Despite placement of these taxa within Endolepis by Stutz et al. Atriplex covillei is possibly more closely allied to the morphologically similar and partially sympatric A. phyllostegia than it is to strongly dissimilar and the distantly disjunct A. suckleyi. Stutz and his associates placed great emphasis on the presence of reduced perianth segments subtending the pistil within the fruiting bracteoles of A. covillei. Calyces per se, otherwise known only in A. suckleyi and A. pleiantha, probably have arisen independently. Their presence does not necessarily indicate a close relationship. Stutz et al. pointed to other differences aside from the calyx of the pistillate flowers, and it is apparent that the two entities can stand as distinct species. To segregate A. covillei within a separate genus and to ally it with a species to which its relationships are obscure at best, stretches logic beyond reason. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 4, p. 354. | FNA vol. 4. |
Parent taxa | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Truncatae | Chenopodiaceae > Atriplex > subg. Obione > sect. Covilleiae |
Sibling taxa | ||
Synonyms | Obione truncata, A. subdecumbens, A. truncata var. stricta | Endolepis covillei |
Name authority | (Torrey ex S. Watson) A. Gray: Proc. Amer. Acad. Arts 8: 398. (1873) | (Standley) J. F. Macbride: Contr. Gray Herb. 53: 11. (1918) |
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