Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to southwestern Washington.
Habitat: Freshwater intertidal marshes, floating logs, and damp gravel.
Flowers: July-September
Origin: Introduced from Europe
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Bumblebees, bees, flies, wasps
Perennial, the stems 4-winged, erect, 4-10 dm. tall.
Leaves opposite, sessile, somewhat clasping, ovate-lanceolate to oblong-ovate, with translucent dots.
Inflorescence of leafy-bracteate cymes; sepals 5, pointed, not black-dotted; petals 5, pale yellow; flowers about 10 mm. wide; stamens numerous, styles 3.
Capsule 3-celled.
Publication: Novitiae Florae Suecicae 236. 1814.
PNW Herbaria: Specimen records of Hypericum tetrapterum in the Consortium of Pacific Northwest Herbaria database.
WA Flora Checklist: Hypericum tetrapterum checklist entry.
OregonFlora: Hypericum tetrapterum information.
E-Flora BC: Hypericum tetrapterum atlas page.
CalPhotos: Hypericum tetrapterum photos.
USDA Plants: Hypericum tetrapterum information.
