Montana Field Guide

One-flowered Cinquefoil is an herbaceous perennial with erect or ascending stems 5-15 cm high that arise from a branched rootcrown. The basal leaves have slender petioles and 3 deeply toothed, elliptic leaflets 1-2 cm long. The 1-2 alternate stem leaves are similar but much smaller. The lower leaf surfaces and upper stems are densely covered with long, tangled, gray hairs, while the upper surfaces, petioles, and lower stems are sparsely covered with stiff, straight hairs. 1-2 stalked flowers are borne at the top of the stem. The saucer-shaped flowers have 5 lance-shaped, long-hairy sepals 3-4 mm long, 5 yellow, oblong petals 4-5 mm long with shallowly lobed tips, 20 stamens, and numerous pistils. The slender style is attached near the top of the achene, which is finely bumpy near its base.

Flowering in late June - July.

There are many similar-appearing species of Potentilla. A technical key and hand lens or microscope are required for positive determination. Potentilla nivea has lower stems and petioles that are covered with long tangled hairs; P. hyparctica has leaves that are only sparsely hairy beneath.

Open, gravelly slopes and ridgetops in the alpine zone.

POLLINATORS
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus bifarius, Bombus fervidus, Bombus frigidus, Bombus rufocinctus, Bombus occidentalis, Bombus pensylvanicus, Bombus impatiens, and Bombus flavidus (Thorp et al. 1983, Wilson et al. 2010, Colla and Dumesh 2010, Colla et al. 2011, Koch and Strange 2012, Koch et al. 2012, Williams et al. 2014).