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Geyer's onion

cultivated onion, garden onion

Bulbs

2–10+, not rhizomatous, ovoid or more elongate, 1–2.5 × 0.8–2 cm;

outer coats enclosing 1 or more bulbs, gray or brown, reticulate, cells rather coarse-meshed, open, fibrous;

inner coats whitish, cells vertically elongate and regular or obscure.

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, usually green at anthesis, usually 3–5, sheathing less than 1/4 scape;

blade solid, ± straight, flat, channeled, (6–)12–30 cm × 1–3(–5) mm, margins entire or 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

persistent, solitary, erect, terete or somewhat 2-angled, 10–50 cm × 1–3 mm.

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

Umbel

persistent, erect, compact, 10–25-flowered, hemispheric to globose, not producing bulbils, or 0–5-flowered, largely replaced by ovoid, acuminate bulbils;

spathe bracts persistent, 2–3, mostly 1-veined, ovate to lanceolate, ± equal, apex acuminate, beakless.

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

urceolate-campanulate, (4–)6–8(–10) mm;

tepals erect or spreading, pink to white, ovate to lanceolate, ± equal, not withering in fruit and permanently investing fruit, or withering if fruit not produced, midribs papillose, becoming callous-keeled, margins often obscurely toothed, apex obtuse to acuminate;

stamens included;

anthers yellow;

pollen yellow;

ovary when present, inconspicuously crested;

processes 6, central, low, distinct or connate in pairs across septa, ± erect, rounded, margins entire, becoming variously developed or obsolete in fruit;

style linear, ± equaling stamens;

stigma capitate, unlobed or obscurely lobed;

pedicel becoming rigid and stiffly spreading in fruit, 8–13 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 each with minute, central papilla.

coat not known.

Allium geyeri

Allium cepa

Phenology Flowering Jun–Aug.
Habitat Disturbed sites adjacent to areas where cultivated
Elevation 0–500 m (0–1600 ft)
Distribution
from USDA
w North America
[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

Varieties 2 (2 in the flora).

(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.)

Key
1. Umbel fully floriferous, not producing bulbils, ovaries mostly all producing seeds.
var. geyeri
1. Umbel not fully floriferous, producing 0–5, mostly sterile flowers, flowers mostly replaced by ovoid, acuminate bulbils.
var. tenerum
Source FNA vol. 26, p. 237. 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. 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. 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
Subordinate taxa
A. geyeri var. geyeri, A. geyeri var. tenerum
Name authority S. Watson: Proc. Amer. Acad. Arts 14: 227. (1879) Linnaeus: Sp. Pl. 1: 301. (1753)
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