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

Kleberg orach, Kleberg's saltbush

Habit Herbs, simple or freely branched, 0.5–6 dm; branches rather stout, angled, scurfy when young. Herbs, with ligneous vertical taproot 5–9 mm thick; bark pale.
Stems

erect, diffuse;

branches alternate, numerous, horizontal or distally ascending, terete, 1.5–4 dm, densely white farinose when young, glabrate in age;

bark becoming pale brownish white and flaky;

internodes mostly shorter than 1(–2.4) cm.

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).

alternate, proximalmost subopposite, sessile;

blade ovate-deltoid, 0.5–1.5(–2.5) × 5–12(–15) mm, rather firm and flat, base rounded, truncate, or slightly clasping, margin entire or toothed, apex acute, very densely canescent-farinose with a greenish yellow tinge.

Flowers

in axillary glomerules and terminal, interrupted spikes.

sessile, axillary, inconspicuous, mostly in leafy lateral branches with extremely short internodes, arising toward tips of secondary branches.

Staminate flowers

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

in most distal axils, 2 mm wide;

sepals 3–5, mostly hyaline, curved elliptic, 1.5–1.7 mm, mucronulate, farinose dorsally.

Pistillate flowers

densely farinose;

bracteoles adnate to ovary.

Seeds

brown, 1.5–2 mm wide;

radicle superior or lateral.

dark reddish brown, round-lenticular, 1.5 mm wide, shining;

radicle superior.

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 variably and irregularly 3–7-cleft, ovate-orbicular, 3.1–4.7 × (3.2–)4–7 mm, typically somewhat constricted below middle, with terminal lobes (1–)1.5–2.8 mm, densely scurfy, faces doubly cristate or smooth.

2n

= 18, 36, 54.

Atriplex argentea

Atriplex klebergorum

Phenology Flowering summer.
Habitat In silty or clay loam soils
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
TX; of conservation concern; near sea level
[BONAP county map]
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.)

Of conservation concern.

The species was noted by its author as apparently belonging in sect. Argenteae Standley; I concur with that alignment. The overall shape of the bracteoles with a subterminal constriction is reminiscent of those of Atriplex powellii, but the bracteole shape is otherwise distinctive, and the long marginal teeth and occasional elongate cristate processes on the faces are unmatched elsewhere in the Argenteae.

(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. 353.
Parent taxa Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Argenteae Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Argenteae
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. 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
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
Name authority Nuttall: Gen. N. Amer. Pl. 1: 198. (1818) M. C. Johnston: SouthW. Naturalist 6: 49. (1961)
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