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lady's leek, nodding onion

Tolmie'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.

1–10+, not clustered on stout primary rhizome, not forming rhizomes, renewal bulbs formed within coats of parent bulb, or borne terminally on rhizomes outside coats of parent bulb, parent bulb disappearing by anthesis except for still-functional roots and shriveled bulb coat, ovoid or oblique, 0.6–2 × 1–2.5 cm;

outer coats enclosing 1 or more bulbs, brown, membranous, lacking cellular reticulation or cells arranged in only 2–3 rows distal to roots, ± quadrate, without fibers;

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

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.

forming abcission layer at soil surface and deciduous or persistent with scape after seeds mature, also frequently breaking at soil surface after pressing, withering at tip at anthesis, 2, basally sheathing, sheaths not extending much above soil surface;

blade solid, flat, ± falcate, 10–40 cm × 1–10 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.

deciduous or persistent, solitary, erect, solid, compressed to strongly flattened and winged or not, 5–40 cm × 1–5 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 to ± loose, 10–50-flowered, globose to hemispheric, bulbils unknown;

spathe bracts persistent, 2–3, 8–17-veined, ovate to lanceolate, ± equal, apex acuminate.

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 to ± stellate, 6–12 mm;

tepals ± erect, almost white to pink, with prominent, darker midribs, lanceolate, ± equal, becoming rigid, spreading, carinate in fruit, margins entire, apex acute to acuminate, involute at tip;

stamens included to ± equaling tepals or exserted;

anthers purple to yellow;

pollen yellow;

ovary crestless or obscurely to prominently crested;

processes 3 or 6, central, low, rounded to ± prominent, triangular, margins entire;

style linear, ± equaling stamens;

stigma capitate, unlobed or obscurely lobed;

pedicel 5–25 mm.

Seed

coat dull or shining;

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

coat dull;

cells smooth.

2n

= 14.

Allium cernuum

Allium tolmiei

Phenology Flowering Jul–Oct.
Habitat Widely distributed on moist soils in mountainous and cool regions
Elevation 600–3500 m (2000–11500 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 USDA
w United States
[WildflowerSearch map]
[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.)

Varieties 2 (2 in the flora).

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

Key
1. Bulbs ovoid, not rhizomatous to oblique, short-rhizomatous; scape 5–28 cm; leaf blade 1.25–2 times scape; stamen 1/2–3/4 tepals; widespread.
var. tolmiei
1. Bulbs ovoid, never rhizomatous; scape 10–40 cm; leaf blade shorter than to ± equaling scape; stamen ± equaling tepals or exserted; known only from s end of Seven Devils Mountains, w Idaho.
var. persimile
Source FNA vol. 26, p. 247. FNA vol. 26, p. 272.
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. 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. tribracteatum, A. tricoccum, A. triquetrum, A. tuberosum, A. tuolumnense, A. unifolium, A. validum, A. victorialis, A. vineale, A. yosemitense
Subordinate taxa
A. tolmiei var. persimile, A. tolmiei var. tolmiei
Synonyms A. allegheniense, A. oxyphilum, A. recurvatum
Name authority Roth: Arch. Bot. (Leipzig) 1: 40. (1798) Baker: Bot. Mag. 32: under plate 6227. (1876)
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