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mountain swamp onion, swamp onion

red Sierra onion, red Sierran onion

Bulbs

1–3, larger bulbs each usually with cluster of 10–30 easily detached bulbels to one side of base, not clustered on stout, primary rhizome, globose to ovoid, 1–1.6 × 0.8–1.5 cm;

outer coats enclosing 1 or more bulbs, brownish, membranous, without fibers;

inner coats white to pink;

inner and outer coats frequently without obvious reticulations, these, when present, contorted.

1–5, not clustered on stout primary rhizome, ovoid, 1–2 × 0.8–1.8 cm;

outer coats enclosing 1 or more bulbs, brown, membranous, cellular-reticulate, cells quadrate, polygonal, or ± rectangular, ± transversely elongate, without fibers;

inner coats white, reticulation absent or cells obscure, ± quadrate.

Leaves

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

blade solid, flat or channeled, 10–25 cm × 1–4 mm, margins entire.

usually deciduous with scape, withering from tip at anthesis, 1–2, basally sheathing, sheaths not extending much above soil surface;

blade solid, flat or broadly channeled, ± falcate, 5–22 cm × 0.5–14 mm, margins entire.

Scape

persistent, solitary, erect, solid, ± terete, sometimes ridged, 10–20 cm × 1–2 mm.

usually forming abcission layer and deciduous with leaves after seeds mature, frequently breaking at this level after pressing, solitary, erect, solid, terete, 2–17 cm × 0.5–2 mm.

Umbel

persistent, erect, compact, 10–20-flowered, hemispheric, bulbils unknown;

spathe bracts persistent, 2, 5–7-veined, ovate, ± equal, apex acuminate.

persistent, erect, compact, 6–65-flowered, hemispheric, bulbils unknown;

spathe bracts persistent, 2–3(–5), 5-8-veined, ovate, ± equal, apex abruptly acuminate to apiculate.

Flowers

campanulate, 6–10 mm;

tepals erect or ± spreading, white with prominent green or pink midveins, lanceolate, ± equal, becoming papery in fruit, margins entire, apex obtuse to acuminate, becoming involute at tip;

stamens included;

anthers white or yellow;

pollen yellow;

ovary crestless or obscurely crested;

processes 3, low, central, rounded, minute;

style linear, equaling stamens;

stigma capitate, unlobed or slightly lobed;

pedicel 5–12 mm.

campanulate, 4–12 mm;

tepals erect, white or pink with dark purplish midveins, lanceolate to oblong-elliptic, ± equal, becoming papery in fruit, margins entire, apex obtuse to acute;

stamens included;

anthers yellow or purple;

pollen yellow;

ovary crested;

processes 3, obscure to ± prominent, rounded, central, margins entire;

style linear, equaling stamens or longer;

stigma capitate, scarcely thickened, obscurely 3-lobed;

pedicel 2–14(–20) mm.

Seed

coat dull;

cells ± smooth.

coat dull;

cells ± smooth.

2n

= 28, 42.

Allium madidum

Allium obtusum

Phenology Flowering May–Jul.
Habitat Seasonally wet meadows
Elevation 1100–2000 m (3600–6600 ft)
Distribution
from FNA
ID; OR
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV
[WildflowerSearch map]
[BONAP county map]
Discussion

Allium madidum is found in the Blue Mountains, Oregon and in Idaho near Payette Lake and New Meadows.

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

Varieties 2 (2 in the flora).

Allium obtusum is known only from the Sierra Nevada.

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

Key
1. Leaf blade 0.5–4 mm wide; umbels 6–20-flowered; tepals white with prominent, dark midveins, oblong-elliptic, apex obtuse.
var. obtusum
1. Leaf blade 2–14 mm wide; umbels 10–65-flowered; tepals pink with darker midveins, lanceolate, apex acute.
var. conspicuum
Source FNA vol. 26, p. 255. FNA vol. 26, p. 269.
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. 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. 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. obtusum var. conspicuum, A. obtusum var. obtusum
Name authority S. Watson: Proc. Amer. Acad. Arts 14: 228. (1879) Lemmon: Pittonia 2: 69. (1890)
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