Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho and Montana.
Habitat: Dry, open forest from low to middle elevations.
Flowers: July-September
Origin: Native
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Self-pollination, flies
Herbaceous terrestrial perennials, 9-70 cm tall, erect, glabrous; stems unbranched, not angled, may be swollen or uniform toward base; roots tuberous, few.
Leaves few, prostrate, ephemeral, basal; blades sessile, lanceolate to oblanceolate, 7.5-32 cm long and 1-8.4 cm broad, barely folded along midvein; cauline bracts linear-lanceolate.
Inflorescence a sparsely to densely flowered raceme, 6-70 cm; rachis typically longer than peduncle; bracts 3-23 mm; flowers green, sometimes slightly translucent; fragrance emits at night but lingers during day, faint, musky to honeylike; sepals 2-6 mm long and 1-3 mm broad; dorsal sepal ovate to oblong; lateral sepals spreading to strongly curving outward, oblong-lanceolate to oblong; petals erect-spreading or projecting, generally straight sided, unevenly ovate to narrowly lanceolate, 2-5.5 mm long and 0.6-2 mm broad, inner margins form a U shape; labellum somewhat bent downward, widely ovate to narrowly elliptic, 2-5 mm long and 1-3 mm broad, apex commonly curving upward slightly; spur horizontal to curving downward, 2-5.5 mm, approximately equal to labellum; viscidia widely elliptic-ovate, 0.15-0.5 mm long and 0.1-0.3 mm broad; rostellum blunt.
Capsules 3.5-10.5 mm; seeds tan to cinnamon brown.
PNW Herbaria: Specimen records of Platanthera elongata in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Platanthera elongata checklist entry
OregonFlora: Platanthera elongata information
E-Flora BC: Platanthera elongata atlas page
CalPhotos: Platanthera elongata photos