Synonyms: Lysimachia greeneana, Lysimachia longipedicellata, Lysimachia membrenacea, Nummularia ciliata, Steironema ciliata, Steironema ciliatum, Steironema longipedicellatum, Steironema membranaceum, Steironema pumilum
Fringed loosestrife is an erect plant with stems rising from 30-120 cm in height from creeping rhizomes. The stem leaves are ovate to broadly lanceolate with rounded to hear-shaped bases, the blades 5-15 cm long and 3-6 cm wide. The petioles are 5-20 mm long. The leaf venation is simple pinnate.
The flowers arise from the upper leaf axils via slender, arched pedicels. The 5 sepals are 5-7 mm long and lanceolate-acuminate in shape. The yellowish petals are obovate in shape and about 1 cm long. 5 stamens are present with the anthers about 3 mm long.
Fringed loosestrife may be found in damp meadows, and along the shores of ponds, lakes or streams and rivers.
Fringed loosestrife may be found over much of temperate North America. It may be found from British Columbia south along the east side of the Cascades to Oregon, where it is found westward to Multnomah County, OR. It may be found eastward through eastern Washington and northeastern Oregon through Idaho and Montana, and further east to Nova Scotia. It may also be found south to New Mexico.
In the Columbia River Gorge, it may be found from the western end of the gorge to about Bingen, WA, and is found between the elevations of 0'-1800'.