Marsh cinquefoil as seen at Lost Lake Fen, Okanogan National Forest.......July 12, 2015.
Marsh cinquefoil is rhizomatous perennial with reddish stems to 1 meter in length which either ascend, float, or are prostrate on the ground where roots may take hold at the nodes. The herbage is smooth-surfaced below and becoming hairy and purplish-glandular above. The basal leaves are pinnately compound with 5-7 obovate, oblong, or elliptic-oblong leaflets from 3-6 cm long. The margins are toothed, and the upper surface is light green while the lower surface is paler with a few to numerous silky hairs.
The flowers are in open cymes, the 5 petals purple or a deep wine red color. Individual petals are ovate-lanceolate to elliptic or spatulate with pointed tips. The 5 sepals are ovate-lanceolate to lanceolate in shape, 7-11 mm long, and with pointed tips. There are about 25 stamens and many pistils.
Marsh cinquefoil is found in wet meadows, marshes, bogs, and along the banks of creeks and margins from sea level to subalpine habitats.
Marsh cinquefoil may be found from Alaska south along the Pacific coast to northern California and east to Labrador and Greenland, Ohio, Iowa, and Wyoming.
Marsh cinquefoil from McClellan Meadows in the Gifford Pinchot N.F.......July 28, 1991.