Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Idaho, eastward across northern Canada to eastern North America.
Habitat: Wet places, including meadows, fields, lawns, and vernally moist sites, sometimes aquatic and floating, low to moderate elevations.
Conservation Status: Not of concern
Delicate annual with slender, weak, decumbent, branching stems 3-20 cm. long, tending to root at the nodes.
Leaves opposite, usually several pairs, rhombic-obovate to oblanceolate, 4-15 mm. long and 1-7 mm. wide, narrowed to short petioles.
Flowers 3-7 in lax racemes, the pedicels recurved, slender, mostly 3-10 mm. long; sepals 2, 1 mm. long; corolla white, about equal to the sepals, the tube about equal to the 5 lobes, which are often unequal in length and width; stamens 3, attached to the corolla tube; style 1, stigmas 3, elongate
Capsule obovoid, 1.5 mm. long.