This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Depressed alpine or arctic shrubby plants, with alternate mainly 3-foliolate stipulate leaves, and cymose flowers on scape-like nearly leafless peduncles. Calyx slightly concave, 5-lobed, 5-bracteolate, persistent. Petals 5, oblong or oval, much smaller than the calyx-lobes, yellow. Stamens 5, opposite the calyx-lobes, inserted on the margin of the villous-pubescent disk. Carpels 5-10, on short pubescent stipes; style lateral. Achenes 5-10, glabrous. [Named in honor of Robt. Sibbald, a Scotch naturalist.]
About 5 species, natives of the colder parts of the north temperate zone. The following typical one is the only known American species.
Sibbaldia procumbens L. Sp. Pl. 284. 1753.
Potentilla procumbens Clairv. Man. Herb. Suisse 166. 1811.
Densely tufted, stem woody, decumbent or creeping, a few inches long. Stipules membranous, lanceolate or ovate-lanceolate, adnate; leaves 3-foliolate; petioles slender, 2'-4' long; leaflets obovate or oblanceolate, cuneate at the base, 3-5-toothed at the apex, pubescent with scattered hairs on both sides, resembling in outline those of Sibbaldiopsis tridentata; peduncles axillary, nearly naked, about equalling the leaves; flowers yellow, about 2$" broad, numerous; petals oblong or oval, very small; calyx-lobes oblong-ovate, acute, longer and broader than the bractlets.
Summits of the White Mountains; Mt. Albert, Quebec; Labrador, Greenland, arctic America to Alaska, south in the Rocky Mountains to Colorado and Utah and to California. Also in arctic and alpine Europe and Asia. Summer.