Atriplex heterosperma |
Atriplex coulteri |
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orach, Russian atriplex, Russian atriplex orach |
Coulter's orach, Coulter's orache, Coulter's saltbush |
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Habit | Herbs, monoecious, erect, branching from base, mostly 5–15 dm. | Herbs, perennial, sometimes flowering as an annual, spreading 0.7–10 dm, slightly woody at base. |
Stems | frequently tinged with red, much branched, sparsely scurfy. |
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Leaves | alternate except proximal-most; petiole 2–3 cm; blade green on both sides, triangular to lance-triangular, 30–120 × 12–90 mm, hastate or subcuneate, margin subentire or irregularly dentate, farinaceous at first, finally glabrous. |
many, sessile or short petiolate; blade obovate, oblong, oblanceolate, or elliptic, (5–)7–20 × 1–3(–5) mm, base cuneate, margin entire, apex acute. |
Flowers | in terminal or axillary pyramidal panicles 6–25+ cm. |
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Staminate flowers | 5-merous, with bracteoles free to base. |
in glomerules in distal axils and short terminal spikes. |
Pistillate flowers | dimorphic, all bracteolate and lacking sepals. |
in small axillary clusters. |
Seeds | vertical; of larger bracteoles yellowish brown, flat, 2–3 mm wide, dull; of smaller bracteoles black, 1.5 mm wide or less, shiny; radicle inferior, basal. |
brown, 1.3–1.5 mm. |
Fruiting | bracteoles orbiculate-ovate, of 2 sizes; larger ones 5–6 × 5 mm; smaller ones 2 × 2 mm, margin entire, surfaces smooth. |
bracteoles sessile or subsessile, broadly obovate, 2–3 mm and as broad or about as broad, united 1/2 of length, margin free, deeply and sharply dentate, narrowed at summit, faces smooth or sometimes tuberculate. |
2n | = 36. |
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Atriplex heterosperma |
Atriplex coulteri |
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Phenology | Flowering summer–fall. | Flowering spring–fall. |
Habitat | Riparian and palustrine (less commonly ruderal) habitats | Somewhat alkaline or clay low places, valley grasslands, coastal sage scrub, coastal slopes |
Elevation | 0-2000 m (0-6600 ft) | 0-500 m (0-1600 ft) |
Distribution |
CA; CO; ID; ME; NE; NV; NY; OR; SD; UT; WY; AB; BC; MB; ON; QC; Eurasia [Introduced in North America]
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CA
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Discussion | Russian atriplex occurs with greasewood, saltgrass, cottonwood, tamarix, and weedy annuals. It is a handsome, vigorous ruderal, weedy annual indigenous to Europe east to Chinese Turkestan that appears to be invading saline lowland and other disturbed areas throughout much of North America. It is similar to Atriplex prostrata from which it can be distinguished by the entire margin and smooth surfaces of the fruiting bracteoles. Additionally, the leaves are thick-textured and often bear one or more lobes or teeth irregularly along the blade above the subbasal main hastate lobe. The staminate spikes when young are very slender, mainly less than 2.5 mm thick. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Atriplex coulteri is closely allied to the geographically disjunct A. fruticulosa, from which it is said to differ in the compressed, small (2.5–3 mm) versus thickened and larger (3–5 mm) bracts. Specimens of A. fruticulosa, including the type, examined by me have bracteoles compressed-thickened, but hardly “globoid” as stated in the key to the species by H. M. Hall and F. E. Clements (1923). Additional specimens borrowed from California might clarify the situation; otherwise the two species are sufficiently close as to be treated as a single entity. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 4, p. 336. | FNA vol. 4, p. 363. |
Parent taxa | Chenopodiaceae > Atriplex > subg. Atriplex > sect. Teutliopsis | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Arenariae |
Sibling taxa | ||
Synonyms | Obione coulteri | |
Name authority | Bunge: Beitr. Fl. Russl., 272. (1852) | (Moquin-Tandon) D. Dietrich: Syn. Pl. 5: 537. (1852) |
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