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tanners canyon onion

lady's leek, nodding onion

Bulbs

usually 1 of a cluster, sometimes short-rhizomatous basally, elongate, to 5 × 1–1.5 cm;

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

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

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.

Leaves

persistent, green at anthesis, 3–6, sheathing;

blade solid, flat, broadly channeled, 25–50 cm × 3–7 mm, margins entire or minutely denticulate.

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.

Scape

persistent, solitary, erect, terete or ± 4-angled, 30–50 cm × 1–3.5 mm.

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.

Umbel

persistent, erect, loose, 10–25-flowered, hemispheric-globose, bulbils unknown;

spathe bracts persistent, 2–3, 3–5-veined, lanceolate, ± equal, apex long-acuminate.

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

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

Flowers

± stellate, 5–10 mm;

tepals spreading or reflexed, white or pink, lanceolate, ± equal, withering in fruit and exposing capsules, margins entire, apex acute, midrib becoming noticeably thickened;

stamens ± equaling tepals to exserted;

anthers purple;

pollen light yellow;

ovary conspicuously crested;

processes 6, central, usually connate in pairs across septa, ± erect, flattened, to 2 mm, margins lacerate, usually well developed in fruit;

style linear, equaling stamens;

stigma capitate, unlobed or obscurely lobed;

pedicel 15–25 mm, elongating in fruit.

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.

Seed

coat shining;

cells each with minute, central papilla.

coat dull or shining;

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

2n

= 28.

= 14.

Allium plummerae

Allium cernuum

Phenology Flowering Jun–Sep. Flowering Jul–Oct.
Habitat Rocky slopes, stream banks, and marshy ground, mountains Widely distributed on moist soils in mountainous and cool regions
Elevation 1600–2800 m (5200–9200 ft) 600–3500 m (2000–11500 ft)
Distribution
from FNA
AZ; Mexico
[BONAP county map]
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]
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.)

Source FNA vol. 26, p. 242. FNA vol. 26, p. 247.
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. 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. 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. allegheniense, A. oxyphilum, A. recurvatum
Name authority S. Watson: Proc. Amer. Acad. Arts 18: 195. (1883) Roth: Arch. Bot. (Leipzig) 1: 40. (1798)
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