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Olympic onion, scalloped onion

cultivated onion, garden onion

Bulbs

1–6+, replaced annually with new bulbs borne terminally on rhizomes;

rhizomes 1–2, secondary, short;

parent bulb disappearing by anthesis except for still-functional roots and shriveled bulb coat, oblique-ovoid, 1–2 × 0.8–1.8 cm;

outer coats not or only partially enclosing bulbs, brown to gray-brown, membranous, lacking cellular reticulation or cells arranged in only 2–3 rows distal to roots, ± quadrate, without fibers;

inner coats white, cells very obscurely quadrate or not visible.

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

usually deciduous with scape, withering from tip at anthesis, (1–)2, basally sheathing, sheaths not extending much above soil surface;

blade solid, flat, falcate, 10–33 cm × 1.5–10 mm, margins sometimes minutely denticulate.

persistent, 4–10, sheathing proximal 1/6–1/4 scape;

blade fistulose, usually ± semicircular in cross section, 10–50 cm × 4–20 mm.

Scape

usually forming abcission layer and deciduous with leaves after seeds mature, frequently breaking at this level after pressing, solitary, ± erect, solid, flattened, winged distally, wings frequently crenulate proximal to umbel, 5–15 cm × 1–5 mm.

persistent, solitary, erect, fistulose, inflated below middle, 30–100 cm × 3–20 mm.

Umbel

persistent, erect, compact, 10–25-flowered, conic to hemispheric, bulbils unknown;

spathe bracts persistent, 2, 8–10-veined, lanceolate, ± equal, apex acute.

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

campanulate, 6–12 mm;

tepals erect, pinkish with deeper pink midveins, lanceolate, ± equal, becoming papery in fruit, margins entire, apex acute;

stamens included;

anthers yellow or purple;

pollen yellow;

ovary obscurely crested;

processes 3, central, 2-lobed, minute, margins entire;

style linear, equaling stamens;

stigma capitate, scarcely thickened, unlobed;

pedicel 6–16 mm.

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 smooth.

coat not known.

2n

= 14.

Allium crenulatum

Allium cepa

Phenology Flowering late May–Jul. Flowering Jun–Aug.
Habitat Talus slopes and clay soils, including serpentine, on bald summits and ridges Disturbed sites adjacent to areas where cultivated
Elevation 600–2500 m (2000–8200 ft) 0–500 m (0–1600 ft)
Distribution
from FNA
OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; CA; KS; LA; MT; OR; TX; WA; cultivated in Europe; Asia
[WildflowerSearch map]
[BONAP county map]
Discussion

Allium crenulatum is known only from west of the Cascade Mountains from Vancouver Island to southwestern Oregon, in Jefferson Park, Oregon, and in the Wenatchee Mountains, central Washington.

The disjunct populations of Allium crenulatum in western Oregon are markedly different among themselves and from the more typical representatives to the north. It has thus far proven impossible to draw meaningful taxonomic distinctions among these populations, hence we have followed historical precedent and have placed them all in a single, highly variable species.

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

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.)

Source FNA vol. 26, p. 274. FNA vol. 26, p. 244.
Parent taxa Liliaceae > Allium Liliaceae > Allium
Sibling taxa
A. aaseae, A. abramsii, A. acuminatum, A. ampeloprasum, A. amplectens, A. anceps, A. atrorubens, A. bigelovii, A. bisceptrum, A. bolanderi, A. brandegeei, A. brevistylum, A. burlewii, A. campanulatum, A. canadense, A. cepa, A. cernuum, A. columbianum, A. constrictum, A. coryi, A. cratericola, A. crispum, A. cuthbertii, A. denticulatum, A. diabolense, A. dichlamydeum, A. dictuon, A. douglasii, A. drummondii, A. elmendorfii, A. falcifolium, A. fibrillum, A. fimbriatum, A. fistulosum, A. geyeri, A. gooddingii, A. haematochiton, A. hickmanii, A. hoffmanii, A. howellii, A. hyalinum, A. jepsonii, A. kunthii, A. lacunosum, A. lemmonii, A. macropetalum, A. macrum, A. madidum, A. membranaceum, A. monticola, A. munzii, A. neapolitanum, A. nevadense, A. nevii, A. nigrum, A. obtusum, A. oleraceum, A. paniculatum, A. parishii, A. parryi, A. parvum, A. passeyi, A. peninsulare, A. perdulce, A. platycaule, A. plummerae, A. praecox, A. punctum, A. rhizomatum, A. robinsonii, A. rotundum, A. runyonii, A. sanbornii, A. sativum, A. schoenoprasum, A. scilloides, A. serra, A. sharsmithiae, A. shevockii, A. simillimum, A. siskiyouense, A. speculae, A. stellatum, A. textile, A. tolmiei, A. tribracteatum, A. tricoccum, A. triquetrum, A. tuberosum, A. tuolumnense, A. unifolium, A. validum, A. victorialis, A. vineale, A. yosemitense
A. aaseae, A. abramsii, A. acuminatum, A. ampeloprasum, A. amplectens, A. anceps, A. atrorubens, A. bigelovii, A. bisceptrum, A. bolanderi, A. brandegeei, A. brevistylum, A. burlewii, A. campanulatum, A. canadense, A. cernuum, A. columbianum, A. constrictum, A. coryi, A. cratericola, A. crenulatum, A. crispum, A. cuthbertii, A. denticulatum, A. diabolense, A. dichlamydeum, A. dictuon, A. douglasii, A. drummondii, A. elmendorfii, A. falcifolium, A. fibrillum, A. fimbriatum, A. fistulosum, A. geyeri, A. gooddingii, A. haematochiton, A. hickmanii, A. hoffmanii, A. howellii, A. hyalinum, A. jepsonii, A. kunthii, A. lacunosum, A. lemmonii, A. macropetalum, A. macrum, A. madidum, A. membranaceum, A. monticola, A. munzii, A. neapolitanum, A. nevadense, A. nevii, A. nigrum, A. obtusum, A. oleraceum, A. paniculatum, A. parishii, A. parryi, A. parvum, A. passeyi, A. peninsulare, A. perdulce, A. platycaule, A. plummerae, A. praecox, A. punctum, A. rhizomatum, A. robinsonii, A. rotundum, A. runyonii, A. sanbornii, A. sativum, A. schoenoprasum, A. scilloides, A. serra, A. sharsmithiae, A. shevockii, A. simillimum, A. siskiyouense, A. speculae, A. stellatum, A. textile, A. tolmiei, A. tribracteatum, A. tricoccum, A. triquetrum, A. tuberosum, A. tuolumnense, A. unifolium, A. validum, A. victorialis, A. vineale, A. yosemitense
Synonyms A. cascadense, A. vancouverense, A. watsonii
Name authority Wiegand: Bull. Torrey Bot. Club 26: 135, plate 355, fig. 1. (1899) Linnaeus: Sp. Pl. 1: 301. (1753)
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