Distribution: Occurring east of the Cascades crest in Washington in north-central and northeastern Washington; Alaska to Oregon, east across the northern half of North America to the Atlantic Coast.
Habitat: Wet meadows from the montane to subalpine.
Flowers: June-August
Origin: Native
Growth Duration: Perennial
Conservation Status: Review Group 1 in Washington (WANHP)
Pollination: Self-pollination, flies
Herbaceous perennials, 5-60 cm tall, erect to slightly decumbent, succulent; stems not angled; roots fasciculate, fleshy.
Leaves few to several, becoming reduced to bracts towards inflorescence; blade oblong to narrowly lanceolate, 2.7-23 cm long and 0.4-4 cm broad, somewhat folded lengthwise, base sheathing stem.
Inflorescence a terminal spike, sparse to very dense; flowers resupinate, light green to light yellowish green, with dull yellowish lip, or whitish green when conditions are cool; lateral sepals spreading or bent strongly away from flower center; petals rhombic-ovate to lance-falcate, margins entire; labellum bent strongly downward, or extending forward, or apex adhered to apexes of dorsal sepal and petals, rhombic-lanceolate to lanceolate, not thickened basally, 2.5-6 cm long and 1-1.5 mm broad, base not rounded-dilated, margins entire; spur thicker at apex than base or somewhat cylindric, 2-5 mm; rostellum lobes diverging and directed downward, minute, rounded; pollinaria 2, straight; pollinia 2, turning forward, may be fragmenting, masses of pollen loose and free of anther sacs, trailing down onto stigma, stigma entire; viscidia orbiculate, free; ovary slender to stout, usually 5-13 mm.
Capsules.
PNW Herbaria: Specimen records of Platanthera aquilonis in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Platanthera aquilonis checklist entry
OregonFlora: Platanthera aquilonis information
E-Flora BC: Platanthera aquilonis atlas page
CalPhotos: Platanthera aquilonis photos