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bract orache, glabrous orach, scotland orache

rillscale, saline orache, saline saltbush, spike saltbush, thick-leaf orache, thickleaf orach, thinleaf orache

Habit Herbs, monoecious, prostrate or sprawling, or sometimes erect, branched, (1–)2–10 dm; branches opposite or subopposite. Herbs, monoecious, typically erect and often branching, 3–15 dm; stems green or striped, angular.
Stems

green and striped, often blue-green when fresh, weakly ridged, sparsely scurfy to glabrous.

Leaves

petiole 0.2–2.5(–3.5) cm;

blade all entire or some or all triangular or lance-hastate with lobes spreading to antrorse, 5–100 × 3–80 mm, base abruptly to narrowly cuneate, entire or irregularly toothed.

opposite or subopposite at least proximally;

petiole 1–3 cm;

blade strongly 3-veined from near base, lanceolate to linear-lanceolate or often triangular-ovate or lance-ovate, 30–125 × 25–60(–80) mm, thickened, basal or subbasal lobes spreading to mainly antrorse, obtuse, blade otherwise entire to sparingly dentate, typically scurfy.

Flowers

in loose glomerules, arranged in foliose, interrupted spikes or axillary, terminating stems and branches.

in terminal or terminal on lateral branches, in spiciform spikes, 2–9 cm, naked except at base.

Seeds

dimorphic: brown, 2.5–4 mm wide (often the only ones present), or black, (1.2–)1.5–2.9(–3) mm wide;

radicle median, ± antrorse, of brown seed basal and spreading.

ellipsoid, wider than long, dimorphic: brown, 1.5–3 mm wide, flattened at base, or black, 1–2 mm wide, shiny;

radicle inferior.

Bracteoles

green, becoming black or reddish to yellow brown, sessile or some short stipitate, venation obscure, ovate-triangular to rhombic-triangular, 5–13 mm, margin united almost to middle, with few irregular teeth or entire, apex abruptly acuminate, faces irregularly muricate, tuberculate, or smooth, inflated, spongy inner layer strongly developed at bracteole base.

Fruiting

bracteoles green, blackening in age, sessile, veined or veins obscure, broadly triangular to ovate, 3–10 mm, thick, usually longer than wide, base truncate to obtuse, margin united at base, apex acute lateral angles entire or with short, sharp teeth, faces smooth or with 2 tubercles, with an inflated inner spongy layer.

2n

= 18, 36.

= 36, 54.

Atriplex glabriuscula

Atriplex dioica

Phenology Flowering summer–fall.
Habitat Sea beaches, other saline habitats
Elevation 0-1500 m (0-4900 ft)
Distribution
from FNA
CT; MA; ME; NH; PA; AB; MB; NB; NS; PE; QC; Europe
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; CO; IA; ID; KS; MA; ME; MN; MT; ND; NE; NH; NJ; NM; NV; OK; OR; RI; SD; UT; WA; WY; AB; BC; MB; NF; NS; NU; ON; QC; SK; YT
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 3 (3 in the flora).

Members of the Atriplex glabriuscula complex occupy saline or brackish marshes and saline coastal strands mainly in the eastern maritime provinces of Canada, with extensions in similar habitats into the northeastern United States. They are seldom, if ever, ruderal weeds and appear to be indigenous or perhaps early introduced in some part from similar European habitats. The constituent taxa have been regarded at specific level (P. M. Taschereau 1972; I. J. Bassett et al. 1983). They are, however, alike in all major morphologic features, and are apparently closely allied. For those who wish to treat them at specific level, the names are supplied in the synonymy.

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

The distribution of the species is evidently bipartite, with an eastern coastal series extending northward mainly from New Jersey to Newfoundland and along the St. Lawrence seaway, and perhaps extending to James Bay of Hudson Bay. The western grouping lies mainly west of the 95th meridian of longitude, where it has been collected since early historical times to the present in saline marshes or other saline sites from the Yukon Territory and Northwest Territories, southward to southern California, northern Arizona, northern New Mexico, and Oklahoma.

Rafinesque gave the following information: “Stem upright angular branched, leaves petiolate, deltoid, acute, thick, scaly, the proximal opposite toothed, the distal alternate, hastated, entire: flowers dioical glomerate, male spiked naked, female unequal, sepals deltoid, warty-crested.”

The name Atriplex dioica Rafinesque antedates Chenopodium subspicatum Nuttall by half a year, being published in December 1817. Hence, it is the correct name for the widely ranging species, which has passed most recently under the name A. subspicata. Nuttall’s description of the habitat of Chenopodium subspicatum is: “In saline soils around Mandan Village, Missouri,” a designation of habitat that applies to this day.

The species forms a mirror-image set of specimens with the remarkably similar Atriplex prostrata, from which it may be distinguished in most cases by the thickened, merely ovate to lanceolate leaf blades, and less commonly but in some localities exclusively triangular-hastate to lanceolate, mostly scurfy and prominently 3-veined leaf blades. In some specimens, including the types of both Chenopodium subspicatum and Atriplex carnosa, the blades bear a hastate lobe at or above the base and sometimes match triangular-hastate profile of A. prostrata. The leaves of A. prostrata are typically thin-textured, green, not scurfy, and the veins of the blade are obscure. I. J. Bassett et al. (1983) disallowed within A. dioica (as A. subspicata) any but those with lanceolate blades, including those with the proximalmost leaves with a pair of subbasal hastate lobes. However, there are numerous specimens in which the blades are thickened and transitional in that regard to the triangular-hastate profile as in A. prostrata. Certainly those specimens with triangular or triangular-hastate leaves taken prior to the introduction of A. prostrata sometime late in the nineteenth or early twentieth century, clearly belong to the indigenous A. dioica. Whether there are intermediates between diploid (2n = 18) A. prostrata and tetraploid or hexaploid (2n = 36, 54) A. dioica is not known. There does not seem to be any consistent feature or combination of features by which all specimens can be assigned to one or the other of the two taxa. It seems probable, however, that A. prostrata is a late introduction from Europe, and that it, along with the related A. heterosperma, is now invading habitats previously occupied exclusively by the indigenous A. dioica.

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

Key
1. Bracteoles thin throughout; black seeds 2.0-2.9 mm; bracteoles entire or with tooth on each margin, ovate-triangular
var. acadiensis
1. Bracteoles often if not always spongy-thickened at the base; black seeds rare or lacking, or of various size; bracteoles variously toothed
→ 2
2. Bracteoles sessile or nearly so; inflorescence with leafy bracts throughout; black seeds rare (or lacking), 1.5-2.5 mm; United States and Canada
var. glabriuscula
2. Bracteoles, at least some axillary ones, short stipitate; inflorescence with leafy bracts only near base; black seeds 1.2-2 mm; Canada
var. franktonii
Source FNA vol. 4. FNA vol. 4.
Parent taxa Chenopodiaceae > Atriplex > subg. Atriplex > sect. Teutliopsis Chenopodiaceae > Atriplex > subg. Atriplex > sect. Teutliopsis
Sibling taxa
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. 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. 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
Subordinate taxa
A. glabriuscula var. acadiensis, A. glabriuscula var. franktonii, A. glabriuscula var. glabriuscula
Synonyms A. patula var. subspicata, A. subspicata
Name authority Edmondston: Fl. Shetland, 39. (1845) Rafinesque: Amer. Monthly Mag. & Crit. Rev. 2(2): 119. (1817)
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