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 canadensis L. Sp. Pl. 498. 1753.
Spreading by slender runners 3'-2o long, the pubescence of the stem, petioles and peduncles spreading. Stipules lanceolate, acute, entire or few-toothed; leaves petioled, digitately 5-foliolate (rarely 3-4-foliolate); leaflets oblanceolate, obovate or oblong, obtuse at the apex, narrowed at the base, 6"-1' long, serrate; peduncles slender, axillary, 1-flowered, the first from the axil of the second stem-leaf; flower yellow, 3"-7" broad; petals 5, broadly oval, slightly longer than the acute calyx-lobes and linear-lanceolate bractlets; stamens about 20; style filiform; achenes glabrous; receptacle villous.
Potentilla caroliniÓna Poir., a plant of the Southern States, with longer spreading pubescence, and broadly obovate leaflets which are cuneate at the base, enters our area in southern Virginia and Missouri. It is probably a race of P. canadensis L.
Softly pubescent, annual or biennial, decumbent, ascending or nearly erect, rather stout, bushy, 1°-2° high. Stipules ovate-lanceolate, acute, mainly entire.; leaves all but the uppermost petioled, pinnately 7 - 11-foliolate; leaflets obovate or oval, obtuse, 6"-12" long, sparingly pubescent, narrowed or rounded at the base, crenate, the upper ones commonly confluent or decurrent on the rachis; flowers terminal, loosely cymose, leafy-bracted, yellow, 3"-5" broad; petals obovate, cuneate, about equalling the ovate calyx-lobes and lanceolate bractlets; stamens about 20; style thickened below; achenes glabrous, strongly gibbous.
Shores of the Great Lakes from New York, Ontario and Pennsylvania to Minnesota, south in the Mississippi Valley to Missouri, west to Washington, Oregon and New Mexico. Also in Mexico and Mantchuria. June-Sept.
Minn. 9:16. 1894.
Similar to P. paradoxa, but more spreading and more branched; lower leaves only pinnate, with several leaflets; upper leaves 3-foliolate; teeth of the leaflets acute; inflorescence elongated, falsely racemose; flowers about 2 1/2" broad; calyx-tube sparingly hirsute, short and broad; bractlets and calyx-lobes ovate-oblong, mucronate, 1 1/2" long, petals obo-vate-cuneate, about as long as the calyx-lobes; stamens 10-15; style fusiform; achenes corky-gibbous.
In sandy soil, North Dakota to Missouri and Kansas. June-Sept.