Atriplex pentandra |
Atriplex linearis |
|
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seas hore orach |
slenderleaf saltbush, thinleaf fourwing saltbush |
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Habit | Herbs, annual or perennial, sprawling to erect, often suffrutescent at the base, much branched and clump-forming, 3–10 dm. | Shrubs dioecious, erect, mainly 10–25 dm; branchlets slender, terete. |
Stems | obtusely angled, finely scurfy when young. |
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Leaves | 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. |
sessile; blade narrowly linear-elliptic, 10–50 × 2–3 mm, firm, revolute, often acute apically. |
Staminate flowers | in short, dense, naked terminal spikes or panicles; calyx 5-cleft, lobes green keeled. |
in glomerules borne in slender interrupted mostly paniculate spikes. |
Pistillate flowers | fascicled in axils. |
paniculate or in few-flowered axillary glomerules. |
Seeds | brown, 1–1.5 mm. |
|
Fruiting | 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. |
bracteoles sessile or subsessile, lanceolate to ovate, 4–6 mm, about as wide, each bract with a pair of thin wings 3 mm broad or less, irregularly dentate or laciniate, free tips of bracts much exceeding the wings. |
2n | = 18. |
|
Atriplex pentandra |
Atriplex linearis |
|
Phenology | Flowering summer–fall. | Flowering spring–fall. |
Habitat | Sandy seashores, coastal salt marshes | Saline deserts, with shadscale, Canotia, Yucca, Opuntia, Rhus, and Eriogonum |
Elevation | 0-50 m (0-200 ft) | 0-800 m (0-2600 ft) |
Distribution |
AL; CT; FL; GA; LA; MA; MS; NC; SC; TX; West Indies; South America (Venezuela and Colombia to Peru) |
AZ; CA; nw Mexico (Baja California, Sonora)
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Discussion | 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.) |
Specimens of Atriplex canescens var. macilenta resemble A. linearis. The taxa have been placed together by some previous workers. Nevertheless, the stems of A. linearis are consistently more slender, the leaves proportionally narrower, and the bracts, though smaller, more closely simulate those of A. canescens. Its diploid nature signals a different evolutionary pathway than that for most of A. canescens, considered broadly. Narrow leaves occur within A. canescens, in the broad sense, sometimes with geographic correlation, sometimes not. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 4, p. 362. | FNA vol. 4, p. 381. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Axyris pentandra, A. texana, A. wardii | A. canescens subsp. linearis, A. canescens var. linearis |
Name authority | (Jacquin) Standley: in N. L. Britton et al., N. Amer. Fl. 21: 54. (1916) | S. Watson: Proc. Amer. Acad. Arts 24: 72. (1889) |
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