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maidenhair spleenwort, silver orach, silver orache, silver saltbush, silverscale, silverscale orache, silverscale saltbush, silvery orache

seas hore orach

Habit Herbs, simple or freely branched, 0.5–6 dm; branches rather stout, angled, scurfy when young. Herbs, annual or perennial, sprawling to erect, often suffrutescent at the base, much branched and clump-forming, 3–10 dm.
Stems

obtusely angled, finely scurfy when young.

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).

sessile or short petiolate;

blade paler abaxially, oblong or rhombic-ovate to broadly obovate or narrowly oblong or narrowly elliptic, 10–30 × (1–)3–15 mm, thin, base rounded to cuneate, margin repand-dentate or sinuate-dentate to undulate or distal ones or all of them entire, apex rounded to acute, mucronate, densely white scurfy abaxially, grayish green and usually glabrate adaxially.

Flowers

in axillary glomerules and terminal, interrupted spikes.

Staminate flowers

borne in distal axils, or in short dense spikes or panicles, or intermixed with pistillate, with 4–5-parted calyx.

in short, dense, naked terminal spikes or panicles;

calyx 5-cleft, lobes green keeled.

Pistillate flowers

fascicled in axils.

Seeds

brown, 1.5–2 mm wide;

radicle superior or lateral.

brown, 1–1.5 mm.

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 sessile or with stipes to 0.5 mm, broadly cuneate-orbiculate, compressed, (2–) 2.5–4.5 × (1.5–)2.6–5 mm, usually as broad as or broader than long, much thickened at maturity, united only at truncate or broadly cuneate base, margin deeply and acutely dentate, faces with 2, sometimes swollen, dentate crests or covered with irregular, conic-acute, corky tubercles, seldom smooth.

2n

= 18, 36, 54.

Atriplex argentea

Atriplex pentandra

Phenology Flowering summer–fall.
Habitat Sandy seashores, coastal salt marshes
Elevation 0-50 m (0-200 ft)
Distribution
from FNA
AZ; CA; CO; ID; KS; MT; ND; NE; NM; NV; OK; OR; SD; TX; UT; WA; WY; AB; BC; MB; SK; Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; CT; FL; GA; LA; MA; MS; NC; SC; TX; West Indies; South America (Venezuela and Colombia to Peru)
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.)

D. S. Correll and M. C. Johnston (1970), treated both Atriplex texana and A. wardii at the specific level. The diagnostic features used to distinguish them, dentate versus entire leaf blades and smooth versus tuberculate faces of fruiting bracteoles, fail singly and in combination. Both taxa were regarded by H. M. Hall and F. E. Clements (1923) as variants of typical A. pentandra, and this worker tentatively agrees with those authors’ conclusions. Specimens from Galveston, Texas—the type locality of A. wardii—are apparently intermediate with A. mucronata (see below) and form the basis on which A. wardii was founded. Some of those specimens have been annotated by me and others as A. mucronata. The plants have entire leaves more closely matching those of A. mucronata, but the small fruiting bracteoles, though usually lacking tubercles on the faces, are of similar proportions to those of typical A. pentandra. Atriplex pentandra and A. mucronata are certainly very closely allied.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Plants low, rounded, mainly 1-3(-4.5) dm; fruiting bracteoles sessile or rarely some short stipitate, the appendages mainly acuminate or acute-attenuate; Nevada and adjacent se California, se Oregon
→ 2
1. Plants rather strict and often taller, mainly 2-4(-5) dm; fruiting bracteoles, at least some, short stipitate; appendages acute to less commonly acuminate to attenuate; other distribution
→ 3
2. Leaf blades typically, but not always, constricted to the petiole; herbage merely scurfy, or with elongate trichomes mainly on the fruiting bracteoles; Nevada (except the southern part), and adjacent se California and se Oregon
var. hillmanii
2. Leaf blades typically, if not always, cuneate to a winged petiole or merely sessile base; herbage copiously covered with elongate trichomes throughout, or mostly on the stems and fruiting bracteoles; Nye County, Nevada and adjacent Inyo County, California
var. longitrichoma
3. Leaf blades elliptic to oval, attenuate to a cuneate base; sw Colorado, se Utah, and nw New Mexico
var. rydbergii
3. Leaf blades triangular-ovate to oval, base broadly obtuse to acute or less commonly cuneate; various or other distribution
→ 4
4. Distal leaves short petiolate; proximalmost leaves alternate; plants mostly less than 4 dm; British Columbia to Manitoba, s through Montana, North Dakota, South Dakota, Wyoming, Nebraska, Idaho, Utah, e Nevada, Colorado, w Kansas, ne Arizona, nw New Mexico
var. argentea
4. Distal leaves sessile; proximalmost leaves opposite; plants mostly over 4 dm; California, s Nevada, Arizona, New Mexico, w Oklahoma, w and n Texas
var. mohavensis
Source FNA vol. 4. FNA vol. 4, p. 362.
Parent taxa Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Argenteae Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Arenariae
Sibling taxa
A. acanthocarpa, A. amnicola, A. californica, A. canescens, A. confertifolia, A. cordulata, A. coronata, A. corrugata, A. coulteri, A. covillei, A. dioica, A. elegans, A. fruticulosa, A. gardneri, A. garrettii, A. glabriuscula, A. gmelinii, A. graciliflora, A. heterosperma, A. holocarpa, A. hortensis, A. hymenelytra, A. joaquiniana, A. klebergorum, A. laciniata, A. lentiformis, A. leucophylla, A. lindleyi, A. linearis, A. littoralis, A. matamorensis, A. mucronata, A. nudicaulis, A. nummularia, A. oblongifolia, A. obovata, A. pacifica, A. parishii, A. parryi, A. patula, A. pentandra, A. phyllostegia, A. pleiantha, A. polycarpa, A. powellii, A. prostrata, A. pusilla, A. rosea, A. saccaria, A. semibaccata, A. serenana, A. spinifera, A. suberecta, A. suckleyi, A. tatarica, A. torreyi, A. truncata, A. tularensis, A. watsonii, A. wolfii, A. wrightii
A. acanthocarpa, A. amnicola, A. argentea, A. californica, A. canescens, A. confertifolia, A. cordulata, A. coronata, A. corrugata, A. coulteri, A. covillei, A. dioica, A. elegans, A. fruticulosa, A. gardneri, A. garrettii, A. glabriuscula, A. gmelinii, A. graciliflora, A. heterosperma, A. holocarpa, A. hortensis, A. hymenelytra, A. joaquiniana, A. klebergorum, A. laciniata, A. lentiformis, A. leucophylla, A. lindleyi, A. linearis, A. littoralis, A. matamorensis, A. mucronata, A. nudicaulis, A. nummularia, A. oblongifolia, A. obovata, A. pacifica, A. parishii, A. parryi, A. patula, A. phyllostegia, A. pleiantha, A. polycarpa, A. powellii, A. prostrata, A. pusilla, A. rosea, A. saccaria, A. semibaccata, A. serenana, A. spinifera, A. suberecta, A. suckleyi, A. tatarica, A. torreyi, A. truncata, A. tularensis, A. watsonii, A. wolfii, A. wrightii
Subordinate taxa
A. argentea var. argentea, A. argentea var. hillmanii, A. argentea var. longitrichoma, A. argentea var. mohavensis, A. argentea var. rydbergii
Synonyms Obione argentea Axyris pentandra, A. texana, A. wardii
Name authority Nuttall: Gen. N. Amer. Pl. 1: 198. (1818) (Jacquin) Standley: in N. L. Britton et al., N. Amer. Fl. 21: 54. (1916)
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