Northern Prairie Wildlife Research Center
Western Wetland Flora
Field Office Guide to Plant Species
Tall Swamp Onion
Allium validum S. Wats.
- Family: Lily (Liliaceae)
- Flowering: June-September
- Field Marks: This onion is stout, growing to a height of 3 feet. There are several bulbs formed along a rhizome. The six stamens are exerted above the sepals and petals.
- Habitat: Wet meadows.
- Habit: Perennial herb with several oblongoid to ovoid bulbs formed along a rhizome.
- Stems: Upright, stout, somewhat flattened, up to 3 feet tall, smooth.
- Leaves: Several, basal, flat, elongated, up to 1/2 inch wide, rounded or barely pointed at the tip.
- Flowers: 15-30 in a terminal umber, each flower on a slender stalk 1/2-3/4 inch long.
- Sepals and Petals: 6, similar, free from each other, pink, narrowly lanceolate, up to 1/2 inch long, pointed at the tip.
- Stamens: 6, exerted above the sepals and petals.
- Pistils: Ovary superior.
- Fruits: Capsules nearly spherical, 1/4-1/3 inch in diameter, with several long, slender, not shiny seeds.
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