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Belgian orach, frosted orache

quelite

Habit Herbs, procumbent, many branched, alternate except basally, 0.06–3 dm. Herbs, annual.
Stems

reddish or yellowish, smooth or subangular.

erect, ascending, or procumbent, much branched, obtusely angled, 1–6 dm, stout, scurfy when young.

Leaves

with blade ovate to lance-ovate or lanceolate to oblong, 15–45 mm, large basal lobes, obtuse, cuneate to a short petiole, margin sinuate-dentate, scurfy on both sides.

alternate or proximalmost opposite or subopposite;

petiole to 1.5 cm or sessile;

blade paler abaxially, oblong or oval, lanceolate, or elliptic to broadly obovate or narrowly oblong, 10–40(–60) × (2–)4–20 mm, base rounded to cuneate, margin entire or undulate, rarely with 1–2 teeth, apex rounded to acute, mucronate, thin, often densely white scurfy beneath, grayish green and glabrate above.

Flowers

in glomerules in distal leaf axils, axillary or in short terminal spikes.

Pistillate flowers

fascicled in axils.

Seeds

monomorphic, light brown, 3.5–4 mm wide;

radicle inferior.

reddish brown, 2 mm.

Fruiting

bracteoles whitish green, sessile or subsessile, broadly rhombic, (4–)6–7(–8) mm, thickened at base, becoming scaly in age, cartilaginous in basal 1/2, lateral angles strongly produced and with margin mostly entire, faces smooth or irregular, pointed, or flattened and winglike tubercles in basal 1/2.

bracteoles subsessile or with stipes to 1 mm, cuneate-orbiculate, compressed, 4.5–7 × 3.5–5.6 mm, typically longer than wide, united to middle, apex rounded, 3–5-toothed, teeth subequal, sides irregularly tuberculate or with 2 lateral dentate crests, rarely not appendaged.

Staminate

glomerules terminal or in dense or interrupted, terminal or axillary, naked spikes or shortly branched panicles.

2n

= 18.

= 18.

Atriplex laciniata

Atriplex mucronata

Phenology Flowering summer–fall. Flowering summer–fall.
Habitat Sand, cobble on more or less protected beaches, on Zostera and Fucus wrack Sandy seashores, salt marshes
Elevation 0-50 m (0-200 ft) 0 m (0 ft)
Distribution
from FNA
NB; NS; PE; QC; Europe [Introduced in North America]
[BONAP county map]
from FNA
AL; FL; LA; MA; MD; MS; NC; NH; NJ; TX; VA
[BONAP county map]
Discussion

Atriplex laciniata is evidently rare in North America.

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

Problems with prior applications of the name Atriplex mucronata lie in the mistaken determination of the place of publication as Amer. Monthly Mag. & Crit. Rev. 2: 176. 1818 (where the name is only mentioned), instead of 2: 119. 1817 (where accompanied by a description and notes). H. M. Hall and F. E. Clements (1923) evidently relied on P. C. Standley’s (1916) interpretation, which indicated the wrong citation (see also A. dioica Rafinesque as an identical example). Hall and Clements applied the name mucronata to their interpretation of A. patula subsp. hastata or to A. hastata (i.e., to A. prostrata according to this treatment).

The treatment of Obione by C. H. B. A. Moquin-Tandon (1849) included “A. mucronata Rafin.!” as a synonym of O. arenaria. Possibly a sheet in the Prodromus herbarium at Geneva was the basis for that decision. It has two mounted specimens, one labeled A. arenaria Nuttall, collected by Nuttall in “N. Jersey, 1826,” and a second labeled “Atriplex mucronata Rafinesque (A. arenaria Nuttall, N. Jersey) Maritime NY, Rafinesque 1819.” From that information (although the year is 1819, not 1817), and from the description of the taxon, it seems clear that A. arenaria Nuttall is a later synonym of A. mucronata Rafinesque by at least half a year.

H. A. Gleason and A. Cronquist (1991) indicated that this taxon, by whatever name, is “perhaps better treated as a variety of the more tropical Atriplex pentandra (Jacquin) Standley, but the proper nomenclatural combination not yet made.” The present writer agrees with that conclusion, but such subjugation might indicate further contraction into the species of additional closely related taxa, e.g., A. wrightii, which is clearly closely allied as well.

Plants from the coastal states from New England south to New Jersey are much alike and seldom, if ever, display prominent, terminal, naked spikes or panicles with beadlike glomerules of staminate flowers. Plants from Florida westward sometimes have such staminate spikes or panicles.

Specimens from Florida and some from Texas can be distinguished from Atriplex pentandra only with difficulty, especially those individuals with entire leaves. However, the fruiting bracteole length-width ratio and overall shape, with some allowance for overlap, can serve to distinguish most specimens; those of A. mucronata are proportionately longer than broad and, on average, larger.

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

Source FNA vol. 4, p. 341. FNA vol. 4, p. 362.
Parent taxa Chenopodiaceae > Atriplex > subg. Atriplex > sect. Sclerocalymma Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Arenariae
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. glabriuscula, A. gmelinii, A. graciliflora, A. heterosperma, A. holocarpa, A. hortensis, A. hymenelytra, A. joaquiniana, A. klebergorum, 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. 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
Synonyms A. arenaria, A. cristata var. arenaria, A. pentandra subsp. arenaria
Name authority Linnaeus: Sp. Pl. 2: 1053. (1753) Rafinesque: Amer. Monthly Mag. & Crit. Rev. 2(2): 119. (1817)
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