Stems: tufted, spreading by slender runners. Leaves: petioled, pinnate, leaflets seven to twenty-five, oblong, oblanceolate, obtuse, the lower generally smaller, sharply serrate, smooth above, silky-pubescent below. Flowers: petals broadly oval, entire, exceeding the ovate acute calyx-lobes and oval bractlets. Fruit: receptacle villous, achenes glabrous.
The Silver Weed is a tufted plant, with elongated pinnate leaves composed of from seven to seventeen leaflets, which are sharply toothed, green, and smooth on the top, and very silky and whitish underneath. A characteristic feature of the Silver Weed is the minute pairs of leaflets which grow between the real leaflets, but are merely tiny pointed growths. The yellow flowers, which are typical of the whole genus and have five bracts, five sepals, five petals, and numerous stamens, grow on slender naked stalks that spring from the axils of the leaves. The flowers are very pretty and velvety, and commonly grow in the moist meadows, for there "The Silver Weed with yellow flowers, Half hidden by the leaf of gray,
Blooms on the bank of that clear brook Whose music cheers my lonely way."
The Silver Weed creeps along the ground by means of slender many-jointed runners, and its steins are usually curved and winding. When the fruit ripens it consists of a head formed of several little achenes, or nutlets. The Potentillas are very numerous in the mountain regions.
Potentilla dissect a, or Common Cinque foil, is a low alpine plant, more or less silky and hairy, and has a yellow flower with a five-lobed calyx and five roundish petals. It resembles a miniature rose. The foliage consists of from five to seven toothed leaflets on each stem, the terminal leaflet being three-lobed at the apex.
There are several varieties of this species: Potentilla dissecta var. glaucophylla, or Smooth Cinquefoil, has smooth green leaves; Potentilla dissecta var. multisecta, or Dissected Cinquefoil, has whitish silky foliage, each leaflet being long and narrow; and Potentilla dissecta var. pinnati-secta, or Leafy Cinquefoil, has more numerous leaflets and a one-flowered stem, which grows only about three inches high, the whole plant being smooth, with the exception of the hairy calyx and tufted apices of the leaves.
Many of the Cinquefoils (cinque, "five"; feuilles, "leaves") have five-parted leaves, hence their common name.
Potentilla norvegica, or Rough Cinquefoil, is a coarse weed-like plant, with leaves that are divided into three leaflets, and yellow flowers that grow in rather close leafy clusters.
Potentilla Hippiana, or Woolly Cinquefoil, is a stout plant, with quantities of densely floccose and silky foliage. The leaflets are whitish and woolly on both sides, and deeply dentated. The flowers are bright yellow, and grow in graceful terminal clusters.
Potentilla gracilis, or Small Cinque foil, has very small leaves, heart-shaped in outline and composed of from three to seven leaflets, which are white and woolly beneath and green and silky on the top. The little flowers are yellow.
Potentilla nivea, or Alpine Cinquefoil, grows at great altitudes and is found at 8500 feet. It is a tiny plant, with small trifoliate white and woolly leaves and wee terminal yellow flowers.
In studying the Potentillas it is wise to refer to the Ranunculi, also recorded in this Section, and note the close resemblance yet distinct variations which exist between the two genera. The differences between the foliage of the Potentillas and that of the Ranunculi have already been referred to in the description of the latter plants, but it may be further noted here that the stamens of the Ranunculi are hypogynous, or borne at the base or below the ovary, while those of the Potentillas are perigynous, or borne on the perianth around the ovary.
Potentilla uniUora, or One-flowered Cinquefoil, is densely csespitose, from a woody base, and has small closely tufted leaves palmately divided, the leaflets being deeply cut and very white-woolly on both sides. The bright yellow flowers are solitary on short stalks and the petals are broad, notched at the apex, and much longer than the narrow, densely hairy sepals.
Potentilla jruticosa, or Shrubby Cinquefoil, renders the dry sunny alpine meadows very gay in July and August with its lovely bright yellow flowers, which resemble large buttercups and grow on low bushy shrubs, amid much silvery foliage, composed of tiny compound leaves covered with a soft silky down. The bark on the slender stems is extremely shreddy.