Distribution: Occurring east of the Cascades crest and along the Columbia River in Washington; British Columbia to Oregon, east to the Rocky Mountains, Great Plains, and the central U.S.

Habitat: Shores of strams and lakes, marshes, and other low, wet places in the valleys and foothills.

Flowers: July-September

Origin: Native

Growth Duration: Perennial

Conservation Status: Review Group 1 in Washington (WANHP)

Perennial herbs from a rhizome, the stems 2-10 dm. tall, simple, or branched at the base of the inflorescence.

Leaves opposite, all cauline, the lower reduced, the others 3-10 cm. long and 5-20 mm. wide, sessile, serrate or nearly entire, linear-oblong, the upper lance-ovate near the inflorescence.

Inflorescence a close-flowered, elongate, terminal raceme, the flowers sub-sessile; calyx 4-6 mm. long, finely glandular-pubescent, the 5 teeth short and uneven; corolla lavender-purple, 12-16 mm. long, bilabiate, the lips 3-5 mm. long, the lower 3-lobed; stamens 4, ascending under the upper corolla-lip.

Nutlets 4.