Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains and Nebraska, also from the Great Lakes to the Atlantic Coast.
Habitat: Dry, open woods and gravelly streambanks, low to mid-elevations in the mountains.
Flowers: June-August
Origin: Native
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Self-pollination, flies
Scapose perennials with 1-2 fleshy tubers, glabrous, 2-6 dm. tall.
Leaves 2-4 on the lower third of the stem, often all basal, narrowly lanceolate to broadly oblanceolate, 8-15 cm. long and 10-30 mm. broad, acute to rounded, gradually narrowed to the sheathing base.
Inflorescence a loosely- to densely-flowered, spike-like raceme; floral bracts inconspicuous, seldom over 8 mm. long; flowers sub-sessile, very numerous, spirally arranged; sepals 1-nerved, thin, pale green, the upper one ovate, about 3 mm. long, the lower pair longer but narrower, spreading; petals thicker than the sepals, greenish to nearly white, about equal to the upper sepal, oblong-lanceolate, oblique; lip fleshy, narrowly lanceolate to triangular-ovate, 2.5-4.5 mm. long, fused with the lateral sepals; spur narrowly cylindric, straight, 3-5 mm. long; stamens and style fused to form a very short column.
Capsule erect, scarcely 1 cm. long
PNW Herbaria: Specimen records of Platanthera unalascensis in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Platanthera unalascensis checklist entry
OregonFlora: Platanthera unalascensis information
E-Flora BC: Platanthera unalascensis atlas page
CalPhotos: Platanthera unalascensis photos