Atriplex obovata |
Atriplex argentea |
|||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
broadscale, mound saltbush, New Mexico saltbush, silver saltbush |
maidenhair spleenwort, silver orach, silver orache, silver saltbush, silverscale, silverscale orache, silverscale saltbush, silvery orache |
|||||||||||||||||
Habit | Subshrubs, dioecious, clump forming, mainly 2–8 dm and as wide, woody at base. | Herbs, simple or freely branched, 0.5–6 dm; branches rather stout, angled, scurfy when young. | ||||||||||||||||
Stems | stiffly erect; branchlets terete. |
|||||||||||||||||
Leaves | tardily deciduous, alternate or proximal-most subopposite, shortly petiolate; blade gray green, oblong-ovate to elliptic or orbiculate, 8–30(–35) × 6–20 mm, margin entire or rarely dentate, apex rounded to retuse or obtuse. |
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). |
||||||||||||||||
Flowers | in axillary glomerules and terminal, interrupted spikes. |
|||||||||||||||||
Staminate flowers | yellow, in clusters 2–3 mm wide, borne in panicles 6–30 cm. |
borne in distal axils, or in short dense spikes or panicles, or intermixed with pistillate, with 4–5-parted calyx. |
||||||||||||||||
Pistillate flowers | in small, very numerous glomerules in axils of elongated, terminal leafy-bracteate spikes or finally paniculate. |
|||||||||||||||||
Seeds | brown, 2.4–2.8 mm. |
brown, 1.5–2 mm wide; radicle superior or lateral. |
||||||||||||||||
Fruiting | bracteoles sessile or substipitate, 4–5 × 5–9 mm, base broadly cuneate, margin sharply toothed, apical tooth subtended by 2–6 equal or smaller teeth, faces smooth or rarely tuberculate. |
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. |
||||||||||||||||
2n | = 18, 36, 54. |
|||||||||||||||||
Atriplex obovata |
Atriplex argentea |
|||||||||||||||||
Phenology | Flowering summer–fall. | |||||||||||||||||
Habitat | Fine-textured substrates, with salt desert shrub and lower pinyon-juniper communities | |||||||||||||||||
Elevation | 1500-2000 m (4900-6600 ft) | |||||||||||||||||
Distribution |
AZ; CO; NM; TX; UT; Mexico
|
AZ; CA; CO; ID; KS; MT; ND; NE; NM; NV; OK; OR; SD; TX; UT; WA; WY; AB; BC; MB; SK; Mexico
|
||||||||||||||||
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.) |
|||||||||||||||||
Key |
|
|||||||||||||||||
Source | FNA vol. 4, p. 371. | FNA vol. 4. | ||||||||||||||||
Parent taxa | Chenopodiaceae > Atriplex > subg. Pterochiton | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Argenteae | ||||||||||||||||
Sibling taxa | ||||||||||||||||||
Subordinate taxa | ||||||||||||||||||
Synonyms | A. greggii, A. jonesii, A. obovata var. tuberata | Obione argentea | ||||||||||||||||
Name authority | Moquin-Tandon: Chenop. Monogr. Enum., 61. (1840) | Nuttall: Gen. N. Amer. Pl. 1: 198. (1818) | ||||||||||||||||
Web links |
|