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..
Potentilla multifida L. Sp. Pl. 496. 1753.
Perennial, stems several or many from the caudex, low, asceding or spreading, appressed-silky. Stipules large, lanceolate, acuminate, scarious, brown; leaves pinnately 5-9-foliolate, grayish-tomentose beneath, glabrate above; leaflets finely divided to near the midrib into linear acute segments, with more or less revolute margins; petals yellow, a little exceeding the ovate-lanceolate acute sepals; stamens about 20; style terminal, short, not thickened at the base; achenes smooth, or slightly rugose.
P. bipinnatifida Dougl.; Hook. Fl. Bor. Am. 1: 188. 1833.
P. pennsylvanica bipinnatifida T. & G. Fl. N. Am. 1: 438. 1840.
Perennial; stems several, erect or ascending, usually simple, leafy, finely white-villous, 1° - 1 1/2° high. Leaves pinnate, with ovate or lanceolate stipules often 1 1/2' long; leaflets 7-9, obovate in outline, pectinately deeply divided into linear or linear-oblong obtuse segments, finely silky above, white-tomentose beneath; calyx white-silky, 4" broad in fruit, its lobes ovate, 2" - 2 1/2" long; bract-lets oblong-lanceolate, shorter than the calyx-lobes; stamens about 20; style glandular-thickened at the base.
Plains and hills, Minnesota to Manitoba, Alberta and Colorado. Summer.
Potentilla pectinata Raf. Aut. Bot. 164. 1840.
P. littoralis Rydberg, Bull. Torr. Club 23: 264. 1896
Perennial, tufted, stems ascending or decumbent, branched above, 6-2° high, appressed-silky, or glabrate. Stipules ovate-lanceolate, cleft or entire, acute; basal and lower leaves petioled, pinnately 5-7-foliolate, the leaflets approximate or apparently digitate; leaflets oblanceolate or obovate, incised-pinnatifid into oblong obtuse segments, grayish-pubescent beneath, green and glabrate above, 1/2'-2 1/2' long; flowers yellow, cymose, 4"-5" broad; petals obovate, equalling or slightly exceeding the ovate acute veined sepals and the lanceolate bractlets; stamens 20-25; style thickened below; achenes glabrous.
Coast of Newfoundland and Labrador to Hudson Bav. Quebec and New Hampshire. June-July.
Potentilla pennsylvanica L. Mant. 76. 1767.
P. strigosa Pall.; Tratt. Ros. Monog. 4: 31. 1824.
Stem generally erect, 15' - 30' high, tomentose and more or less villous. Stipules ovate, often much divided; leaves pinnately 5 - 15 - foliolate, grayish tomentose beneath, glabrous above; leaflets oblong or oblanceolate, cleft halfway to the midrib into oblong lobes, margins scarcely revolute; cymes dense, the branches erect; petals yellow, obovate, truncate or slightly emarginate, about equalling the ovate triangular acute sepals and the lanceolate bractlets; stamens 20 - 25; style thickened below; achenes glabrous.
On plains, Hudson Bay to the Yukon, British Columbia, Kansas and New Mexico. Summer.