Allium campanulatum |
Allium cepa |
|
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dusky onion, rosy Sierra onion, Sierra onion |
cultivated onion, garden onion |
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Bulbs | 1–3, producing cluster of stalked basal bulbels distal to roots or filiform rhizomes to 10 cm and terminated by bulbels, ovoid, 1–2 × 0.6–1.4 cm; outer coats enclosing 1 or more bulbs, brown to gray, membranous, cellular-reticulate, cells ± quadrate, walls very sinuous, without fibers; inner coats pink to white, cells obscure, vertically elongate. |
1–3, not rhizomatous, mostly depressed-globose, varying in size from cultivar to cultivar, 5–8 × 3–10 cm; outer coats enclosing 1 or more bulbs, yellowish brown, red, or white, membranous, without reticulation; inner coats white to pink, cells obscure to quadrate. |
Leaves | persistent, withering from tip by anthesis, 2, basally sheathing, sheaths not extending much above soil surface; blade solid, flat, distinctly concave-convex, 8–40 cm × 1–5 mm, margins entire. |
persistent, 4–10, sheathing proximal 1/6–1/4 scape; blade fistulose, usually ± semicircular in cross section, 10–50 cm × 4–20 mm. |
Scape | persistent, solitary or clustered, 1–3, erect, solid, terete, 10–30 cm × 1–5 mm. |
persistent, solitary, erect, fistulose, inflated below middle, 30–100 cm × 3–20 mm. |
Umbel | persistent, erect, loose, 10–50-flowered, ± globose, bulbils unknown; spathe bracts persistent, 2–3, 3–5-veined, ovate to lanceolate, ± equal, apex acuminate. |
persistent, erect, compact, to 500-flowered, globose, bulbils occasionally found; spathe bracts caducous, 2–3, 3–4-veined, ovate, ± equal, apex acute to acuminate. |
Flowers | stellate, 5–8 mm; tepals spreading, rose to purple (rarely white) with darker purple crescent adaxially basally, lanceolate to ovate, ± equal, carinate in fruit, becoming erect, ± shiny, rigid, margins entire, apex acuminate, strongly involute at tip; stamens included; anthers purple; pollen yellow; ovary crested; processes 6, prominent, low, central, triangular, margins minutely denticulate; style linear, ± equaling stamens; stigma capitate, scarcely thickened, unlobed; pedicel 10–20 mm, becoming flexuous and mostly strongly deflexed in fruit. |
stellate to campanulate to urceolate, 3–7 mm; tepals erect to ± spreading, white to pink with greenish midveins, withering in fruit, margins entire, apex obtuse or acute, outer ovate, inner oblong; stamens exserted; anthers white; pollen white; ovary crestless; style linear, ± equaling stamens; stigma capitate, unlobed; pedicel 10–50 mm. |
Seed | coat shining; cells each with minute, central papilla. |
coat not known. |
2n | = 14, 28. |
|
Allium campanulatum |
Allium cepa |
|
Phenology | Flowering late May–Aug. | Flowering Jun–Aug. |
Habitat | Generally sandy soils on open or shaded slopes | Disturbed sites adjacent to areas where cultivated |
Elevation | 600–2600 m (2000–8500 ft) | 0–500 m (0–1600 ft) |
Distribution |
CA; NV; OR
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AR; CA; KS; LA; MT; OR; TX; WA; cultivated in Europe; Asia
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Discussion | The onion of commerce, Allium cepa is widely cultivated as a biennial in North America, Europe, and Asia. It is unknown in the wild and is probably derived from A. oschanini of central Asia. The cultivated form is often polyploid (2n = 16, 32, 54) and possibly of hybrid origin. It exists in numerous cultivars, a few of which form large bulbils in the umbel. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 26, p. 256. | FNA vol. 26, p. 244. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | A. austinae, A. bidwelliae, A. campanulatum var. bidwelliae | |
Name authority | S. Watson: Proc. Amer. Acad. Arts 14: 231. (1879) | Linnaeus: Sp. Pl. 1: 301. (1753) |
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