[Coolworts and Foamflowers West of the Cascade Mountains]

Coolwort, Oneleaf Foamflower

Tiarella trifoliata var. unifoliata

Tiarella trifoliata var. unifoliata on the Monte Carlo Trail, Columbia River Gorge.......July 4, 1993.

Tiarella trifoliata var. unifoliata at Silver Star Mt., Columbia River Gorge (Gifford Pinchot N.F.)........July 4, 1991.

Foam flower is an attractive perennial with leafy stems from 15-40 cm high and numerous basal leaves. The single or clustered stems are erect or spreading. The leaves are like miniature maple leaves. The margins are 3-5 lobed, with toothed edges. The lobes are cut 1/4-1/2 the distance into the middle of the blade above the upper lobes. The basal leaves are up to 12 cm wide and 8 cm long with a heart-shaped base. The upper leaves are similar but smaller with shorter petioles and only 3 lobes.

The inflorescence is an open raceme of small white flowers. The white to reddish petals are linear in shape and fringed at the tips. The calyx is 1.5-3 mm long.


The foam flower may be found in moist shady woods and along stream banks.


The foam flower may be found from southern Alaska south through the Cascade and Olympic Mts. to Santa Cruz County, CA. It may be found eastward to Alberta and south to western Montana, northern Idaho, and northeast Oregon.

Paul Slichter