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mountain swamp onion, swamp onion

Howell's 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.

usually solitary, not clustered on stout, primary rhizome, ovoid to ± globose, 0.9–1.7 × 0.8–2 cm;

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

inner coats light brown to white, 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.

persistent, withering from tip by anthesis, 1, basally sheathing, sheath not extending much above soil surface;

blade solid, terete, 20–55 cm × 1–4 mm.

Scape

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

persistent, solitary, erect, solid, terete, 15–60 cm × 1–3.5 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, 15–100-flowered, hemispheric, bulbils unknown;

spathe bracts persistent, 2–4, 5–8-veined, lanceolate to broadly ovate, ± equal, apex mucronate to acuminate or long-acuminate.

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.

stellate to ± campanulate, 5–8 mm;

tepals spreading to ± erect, white to pink or pale lavender with darker midveins, ovate to oblong, ± equal, becoming papery in fruit, margins entire, apex obtuse;

stamens ± equaling tepals to long-exserted;

anthers yellow or purple;

pollen yellow;

ovary crested;

processes 6, prominent, ± triangular, margins ± irregularly denticulate to laciniate;

style linear, equaling stamens or longer;

stigma capitate, 3-lobed, lobes slender, recurved;

pedicel 6–25 mm.

Seed

coat dull;

cells ± smooth.

coat dull or shining;

cells minutely roughened.

2n

= 28, 42.

Allium madidum

Allium howellii

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
[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 3 (3 in the flora).

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

Key
1. Scape 15–25(–35) cm; umbels generally 15–30 (–50)-flowered; tepals usually white to pink or lavender; ovary crests purple in fresh specimens.
var. howellii
1. Scape 20–60 cm; umbels generally 25–100-flowered; tepals usually white or pale pink; ovary crests white or greenish in fresh specimens.
→ 2
2. Stamens exserted, 2–4 mm.
var. sanbenitense
2. Stamens ± equaling tepals.
var. clokeyi
Source FNA vol. 26, p. 255. FNA vol. 26, p. 250.
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. 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
Subordinate taxa
A. howellii var. clokeyi, A. howellii var. howellii, A. howellii var. sanbenitense
Name authority S. Watson: Proc. Amer. Acad. Arts 14: 228. (1879) Eastwood: Leafl. W. Bot. 2: 109. (1938)
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