Potentilla flabellifolia from the Vista Ridge Trail in the Mt. Hood Wilderness......July 22, 1990.
Fan-leaf cinquefoil is an attractive perennial which forms large clumps of erect to spreading stems from 15-30 cm long. The basal leaves are numerous and these have long petioles with 3 obovate leaflets from 1.5-2.5 cm long. The margins of the leaflets are deeply toothed, and these may have smaller secondary teeth on them. There are usually only one or two smaller leaves on the stem. The upper surfaces of the leaves are often bright green.
The inflorescence is leafy-bracteate cyme of several flowers. The flowers are bright yellow and about 2.5 cm across with 5 obcordate-shaped petals which are up to 10 mm in length. The petals are notched at the tips as seen in the photos and they are longer than the sepals.. The calyx is saucer-shaped and has 5 lobed, sepal-like bracts. The pistils are numerous and there are about 20 stamens.
Fan-leaf cinquefoil may be found on moist meadows and streambanks on subalpine to alpine slopes in the mountains.
Fan-leaf cinquefoil from British Columbia south through the Cascades and Olympics to the Sierra Nevada of California. It may be found eastward through British Columbia to the Rocky Mts. of southeastern Alberta and south through the mountains of Montana and Idaho, and also in the Blue and Wallowa Mts. Of north central and northeastern Oregon.