Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Alberta, Montana, and eastern North America.
Habitat: Wet pastures, ditches, shores, marshes, and seeps.
Flowers: June-August
Origin: Introduced from Eurasia
Conservation Status: Not of concern
Pollination: Wind
[none provided]
PNW Herbaria: Specimen records of Juncus effusus ssp. effusus in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Juncus effusus ssp. effusus checklist entry
OregonFlora: Juncus effusus ssp. effusus information
E-Flora BC: Juncus effusus ssp. effusus atlas page
CalPhotos: Juncus effusus ssp. effusus photos