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swamp onion

Bulbs

1–3; larger bulbs each usually with cluster of 10–30 easily detached bulbils to one side of base, globose to ovoid;

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

Leaves

persistent, green at anthesis, 2;

blades solid; flat or channeled, 10–25 cm × 1–4 mm.

Scapes

persistent; solitary; erect; solid; more or less terete, sometimes ridged, 10–20 cm × 1–2 mm.

Umbels

persistent; erect; compact, 10–20(40)-flowered, hemispheric;

pedicels 5–12 mm;

spathe bracts 2.

Flowers

6–10 mm;

tepals erect or more or less spreading, white with prominent green or pink midveins, lanceolate; more or less equal;

margins entire;

apex obtuse to acuminate, becoming involute at tip;

stamens included;

ovary crestless or obscurely crested with 3 minute processes;

stigma unlobed or slightly lobed.

2n

=28, 42.

Allium madidum

Distribution
[WildflowerSearch map]
[BONAP county map]
Discussion

Open mixed conifer forests, gravelly seeps, seasonally wet meadows and scablands. Flowering May–Jul. 1000–2200 m. BW. ID. Native.

Source Flora of Oregon, volume 1, page 140
Nick Otting, Richard Brainerd, Barbara Wilson
Sibling taxa
A. acuminatum, A. ampeloprasum, A. amplectens, A. anceps, A. bisceptrum, A. bolanderi, A. brandegeei, A. campanulatum, A. cernuum, A. crenulatum, A. dictuon, A. douglasii, A. falcifolium, A. fibrillum, A. geyeri, A. lemmonii, A. macrum, A. membranaceum, A. nevadense, A. nevii, A. nigrum, A. parvum, A. peninsulare, A. platycaule, A. punctum, A. robinsonii, A. sanbornii, A. schoenoprasum, A. siskiyouense, A. tolmiei, A. triquetrum, A. unifolium, A. validum, A. vineale
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