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lady's leek, nodding onion

passey's onion

Bulbs

2–5+, clustered, often short-rhizomatous at base, rhizome not stout or iris-like, oblong, elongate, 1–3 × 0.8–1.5 cm;

outer coats enclosing 1 or more bulbs, grayish or brownish, membranous, minutely striate, cells in regular vertical rows, narrowly elongate, fibers persistent, parallel, few;

inner coats white to pink or reddish, cells in regular vertical rows, narrowly elongate.

2–3+, not rhizomatous, ovoid, 1–2 × 1.2–2 cm;

outer coats enclosing 1 or more bulbs, light brown, reticulate, fibrous;

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

Leaves

persistent, green at anthesis, 3–5, basally sheathing, sheaths not extending much above soil level;

blade solid, flat, channeled to broadly V-shaped in cross section, 10–25 cm × 1–6 mm, margins entire or denticulate.

persistent, green at anthesis, 2–3, sheathing;

blade solid, flat, ± falcate, 10–20 cm × 3–6 mm, margins entire.

Scape

persistent, sometimes 2 or more produced successively from single bulb, usually clustered, nodding, solid, terete or ridged, particularly distally, sometimes flattened and narrowly winged, abruptly recurved near apex, 10–50 cm × 1–3 mm.

persistent, solitary, erect, terete or ± winged-angled, mostly 10–20 cm × 1–2.5 mm.

Umbel

persistent, cernuous, loose, 8–35-flowered, hemispheric, bulbils unknown;

spathe bracts persistent, 2, 3-veined, lanceolate, ± equal, apex acuminate, beakless.

persistent, erect, compact, 8–27-flowered, hemispheric-globose, bulbils unknown;

spathe bracts persistent, 2–4, mostly 1-veined, ovate, ± equal, apex acuminate to caudate.

Flowers

campanulate, 4–6 mm;

tepals ± erect, pink or white, elliptic-ovate, ± equal, withering in fruit, margins ± entire, apex ± obtuse, at least outer tepals strongly incurved, midribs not thickened;

stamens exserted;

anthers yellow;

pollen yellow;

ovary conspicuously crested;

processes 6, flattened, ± triangular, margins entire or toothed;

style exserted, linear, ± equaling stamens;

stigma capitate, scarcely thickened, unlobed;

pedicel 6–25 mm, becoming stouter in fruit, elongating and bending abruptly upward from near point of attachment.

campanulate, 7–9 mm;

tepals erect, light pink, narrowly lanceolate to lance-ovate, becoming callous-keeled, persistent and permanently investing capsule, margins entire, apex acuminate, inner shorter and narrower than outer, outer strongly keeled and gibbous at base;

stamens included;

anthers yellow;

pollen yellow;

ovary obscurely crested;

processes 6, central, ± erect, rounded, minute, to 1 mm, margins entire;

style linear, equaling stamens;

stigma capitate, scarcely thickened, unlobed;

pedicel 10–18 mm.

Seed

coat dull or shining;

cells smooth, minutely roughened, or each with minute, central papilla.

coat shining;

cells smooth, each with minute, central papilla.

2n

= 14.

Allium cernuum

Allium passeyi

Phenology Flowering Jul–Oct. Flowering Jun.
Habitat Widely distributed on moist soils in mountainous and cool regions Shallow, stony, lithosolic soil over dolomitic limestone, hilltops
Elevation 600–3500 m (2000–11500 ft) 1400–1600 m (4600–5200 ft)
Distribution
from FNA
AL; AR; AZ; CO; DC; GA; IA; ID; IL; IN; KY; MD; MI; MN; MO; MT; NC; NE; NM; NY; OH; OR; PA; SC; SD; TN; TX; UT; VA; WA; WI; WV; WY; AB; BC; ON; SK; Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
UT
[BONAP county map]
Discussion

Allium cernuum is the most widespread North American species of the genus. It is closely related to A. stellatum, and the character commonly used to differentiate them has been umbel orientation. In both species, the inflorescence is nodding in bud, but in A. stellatum it usually becomes erect by anthesis. In A. cernuum the peduncle remains permanently recurved near the apex, although the inflorescence may sometimes become erect overall, or nearly so. While this character is helpful in identification, an almost exclusive reliance on it (even by one of the present authors in his youth) has obscured other clearer distinctions between the species and has confused their geographic ranges. More reliable characters for differentiating these species are bulb shape (elongate in A. cernuum, ovoid in A. stellatum) and perianth shape (campanulate in A. cernuum, stellate in A. stellatum). Unfortunately, perianth shape is often difficult to see in herbarium specimens.

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

Of conservation concern.

Allium passeyi is known only from Box Elder County.

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

Source FNA vol. 26, p. 247. FNA vol. 26, p. 242.
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. 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
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. 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. allegheniense, A. oxyphilum, A. recurvatum
Name authority Roth: Arch. Bot. (Leipzig) 1: 40. (1798) N. H. Holmgren & A. H. Holmgren: Brittonia 26: 309, figs. 1, 4. (1974)
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