Atriplex coulteri |
Atriplex confertifolia |
|
---|---|---|
Coulter's orach, Coulter's orache, Coulter's saltbush |
shadscale, shadscale saltbush, sheepfat, spiny saltbush |
|
Habit | Herbs, perennial, sometimes flowering as an annual, spreading 0.7–10 dm, slightly woody at base. | Shrubs, dioecious, 3–8 dm, spinescent. |
Stems | frequently tinged with red, much branched, sparsely scurfy. |
|
Leaves | many, sessile or short petiolate; blade obovate, oblong, oblanceolate, or elliptic, (5–)7–20 × 1–3(–5) mm, base cuneate, margin entire, apex acute. |
persistent, alternate; petiole 1–4 mm; blade orbiculate to ovate, elliptic, or oval, 9–25(–45) × 4–20(–25) mm, margin entire, apex obtuse. |
Staminate flowers | in glomerules in distal axils and short terminal spikes. |
yellow, in clusters 2–4 mm wide or in spikes to 1 cm, axillary, in foliose-bracteate, divaricately branched panicles 3–15 cm. |
Pistillate flowers | in small axillary clusters. |
in similar paniculate inflorescences. |
Seeds | brown, 1.3–1.5 mm. |
1.5–2 mm wide. |
Fruiting | 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. |
bracteoles sessile or subsessile, suborbiculate to rhombic or elliptic, 4–12 mm and wide, body indurate, terminal teeth distinct, foliaceous, shorter than bracteoles, entire or toothed below, terminal teeth spreading at maturity, faces smooth, lacking appendages. |
2n | = 18, 36, 54+. |
|
Atriplex coulteri |
Atriplex confertifolia |
|
Phenology | Flowering spring–fall. | Flowering spring–fall. |
Habitat | Somewhat alkaline or clay low places, valley grasslands, coastal sage scrub, coastal slopes | Gravelly to fine-textured soils in greasewood, mat-atriplex, other salt desert shrub, sagebrush, pinyon-juniper, and ponderosa pine communities |
Elevation | 0-500 m (0-1600 ft) | 600-2200 m (2000-7200 ft) |
Distribution |
CA
|
AZ; CA; CO; ID; MT; ND; NM; NV; OR; TX; UT; WY
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Discussion | 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.) |
Shadscale forms hybrids with Atriplex canescens, A. garrettii, A. corrugata, and A. gardneri varieties. It is, however, closely allied to A. parryi and A. spinifera. The plants are widely dispersed, typically on saline substrates but less commonly on essentially non-saline ones, through large areas of the western United States and adjacent Canada and Mexico, on both raw and exposed geological strata and on alluvium. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 4, p. 363. | FNA vol. 4. |
Parent taxa | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Arenariae | Chenopodiaceae > Atriplex > subg. Pterochiton |
Sibling taxa | ||
Synonyms | Obione coulteri | Obione confertifolia, A. collina, A. subconferta, Obione rigida |
Name authority | (Moquin-Tandon) D. Dietrich: Syn. Pl. 5: 537. (1852) | (Torrey & Frémont) S. Watson: Proc. Amer. Acad. Arts 9: 119. (1874) |
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