Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Ditches, slow moving streams, oxbows, and other water bodies, from low to middle elevations in the mountains.
Conservation Status: Not of concern
Glabrous, herbaceous perennial from creeping rhizomes, the simple stems ascending or sometimes erect, 1-10 dm. long.
Leaves opposite, all with short petioles, lanceolate to lance-ovate, or the lower elliptic, 1.5-8 cm. long and 0.6-3 cm. wide, serrate to nearly entire.
Inflorescence of open racemes on long peduncles arising in the leaf axils, 10-25 flowered; calyx of 4 sepals; corolla blue, rotate, 4-lobed, the upper lobe the largest, 5-19 mm. wide; style 2.5-3.5 mm. long; pedicels widely spreading, 5-14 mm. long; stamens 2.
Capsule swollen, about 3 mm. high and wide, slightly notched.