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three-corner leek, three-cornered leek, white flower onion

American garlic, one-leaf onion

Bulbs

5–20+, not clustered on stout primary rhizome, rhizomes absent, increase bulbs absent or ± equaling parent bulbs, never appearing as basal cluster, ovoid, 1–2 × 1–2 cm;

outer coats enclosing renewal bulbs, ± translucent, yellow-brown, obscurely cellular-reticulate, thin, membranous, meshes delicate, cells vertically elongate, contorted, without fibers;

inner coats white, cells obscure, quadrate, or not visible.

solitary, replaced annually by new bulbs borne terminally on secondary rhizome;

rhizomes 1–3, conspicuous, to 5 cm, smooth;

parent bulbs disappearing by anthesis except for still-functional roots and bulb coat, ovoid to oblique-ovoid, 1–2 × 0.8–1.5 cm;

outer coats not enclosing bulbs, pale brown, delicately cellular-reticulate, membranous, cells ± rectangular, without fibers;

inner coats white, cells obscure, ± transversely elongate, contorted.

Leaves

persistent, green at anthesis, 2–3, basally sheathing, sheaths not extending much above soil surface;

blade solid, flat, not falcate, ± carinate, 15–50 cm × 3–15 mm, margins entire.

persistent, green or withering from tip at anthesis, 2–3, basally sheathing, sheaths not extending much above soil surface;

blade solid, flattened, sometimes carinate abaxially, ± falcate, 18–50 cm × 4–10 mm, margins entire.

Scape

persistent, clustered, 1–4, erect, solid, sharply 3-angled, 10–40 cm × 1–10 mm.

persistent, solitary, erect, solid, terete, 20–80 cm × 2–7 mm.

Umbel

persistent, lax, loose, 3–15-flowered, ± 1-sided, bulbils unknown;

spathe bracts persistent, 1–2, 3-veined, narrowly lanceolate, ± equal, apex acute.

persistent, erect, loose, 15–35-flowered, hemispheric, bulbils unknown;

spathe bracts persistent, 2, 6–8-veined, lance-ovate to broadly ovate, ± equal, apex acuminate.

Flowers

becoming pendent, campanulate, 10–18 mm;

tepals erect to spreading, white with prominent green midrib, lanceolate, ± equal, becoming membranous in fruit, margins entire, apex acute;

stamens included;

anthers yellow;

pollen yellow;

ovary crestless;

style linear, ± equaling stamens;

stigma capitate, scarcely thickened, unlobed;

pedicel 15–25 mm.

stellate, 11–15 mm;

tepals spreading, bright pink or rarely white, obovate to ovate, unequal, becoming papery and connivent over capsule, margins entire, apex acute to obtuse or emarginate, inner shorter and narrower than outer;

stamens included;

anthers yellow or purple;

pollen yellow or gray;

ovary crestless, 3-grooved, with thickened ridge on either side of groove;

style linear, equaling stamens;

stigma capitate, scarcely thickened, unlobed or obscurely 3-lobed;

pedicel 15–40 mm.

Seed(s)

coat dull;

cells minutely roughened.

coat dull;

cells minutely roughened.

2n

= 18.

= 14.

Allium triquetrum

Allium unifolium

Phenology Flowering Mar–Apr. Flowering May–Jun.
Habitat Disturbed sites Moist, clay soils, including serpentine, usually along streams
Elevation 0–100 m (0–300 ft) 0–1100 m (0–3600 ft)
Distribution
from FNA
CA; sw Europe [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
Discussion

Allium triquetrum is a garden escape, introduced from southwestern Europe, and is potentially a noxious weed.

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

The long, relatively thick rhizomes that develop annually from the bulbs are very characteristic of Allium unifolium and almost unique in North America. Only A. glandulosum Link & Otto and A. rhizomatum Wooton & Standley have similar rhizomes, but these species are not closely related to A. unifolium.

Allium unifolium is known only from the Coast Ranges.

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

Source FNA vol. 26, p. 257. FNA vol. 26, p. 258.
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. 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. 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. 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. 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. validum, A. victorialis, A. vineale, A. yosemitense
Synonyms A. grandisceptrum, A. unifolium var. lacteum
Name authority Linnaeus: Sp. Pl. 1: 300. (1753) Kellogg: Proc. Calif. Acad. Sci. 2: 112, fig. 35. (1863)
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