Northern Prairie Wildlife Research Center
Western Wetland Flora
Field Office Guide to Plant Species
Leafy White Orchid
Platanthera dilatata (Pursh) Lindl. ex Beck
- Family: Orchid (Orchidaceae)
- Flowering: June-September
- Field Marks: This orchid has white or greenish white flowers, with the spur at least half as long as the lip petal. There are up to 12 lanceolate leaves on the stem.
- Habitat: Bogs, along streams, in marshes, wet meadows.
- Habit: Perennial herb with slender, fleshy roots.
- Stems: Upright, slender to stout, smooth, up to 3 feet tall.
- Leaves: Alternate, simple, up to 12 per stem, narrowly lanceolate to lanceolate, rounded to pointed at the tip, tapering to the base, smooth, up to 12 inches long, up to 2 1/2 inches wide.
- Flowers: Several in racemes, fragrant, white to greenish white.
- Sepals: 3, one of them forming a hood with the petals, up to 1/3 inch long, the other 2 elliptic to lanceolate, up to nearly 1/2 inch long.
- Petals: 3, narrowly to broadly lanceolate, up to 1/3 inch long, the lip petal up to 1/2 inch long, up to 1/4 inch wide; spur more than half as long to as long as the lip petal.
- Stamens: 1.
- Pistils: Ovary inferior.
- Fruits: Capsules ellipsoid, 1/3-1/2 inch long, up to 1/6 inch wide.
- Notes: There is variation in the color of the flower and the length of the spur. The earlier frequently used name for this orchid was Habenaria dilatata.
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