Silvery Cinquefoil (Potentilla argentea)
Originally from Europe, this little flower joins the herds of little five-petaled flowers in our fields. This plant was growing in a grassy area in Highland Park, where it was blooming in the middle of June.
Gray describes the genus (which is large and varied) and the species:
POTENTÍLLA L. CINQEFOIL. FIVE-FINGER. Calyx flat, deeply 5-cleft, with as many bractlets at the sinuses, thus appearing 10-cleft. Petals 5, usually roundish. Stamens many. Achenes many, collected in a head on the dry mostly pubescent or hairy receptacle; styles lateral or terminal, deciduous. Radicle superior. — Herbs, or rarely shrubs, with compound leaves, and solitary or cymose flowers; their parts rarely in fours. (Name a diminutive from potens, powerful, originally applied to P. Anserina, from its once reputed medicinal powers.)
Styles filiform, not glandular at base; inflorescence cymose.
Style terminal; achenes glabrous; stamens 20; herbaceous perennials, with rather large yellow petals.
Flowers in loose leafy cymes.
P. argéntea L. (SILVERY C.) Stems ascending or depressed, 1-5 dm. long, paniculately branched at the summit, many-flowered, white-woolly; leaf lets 5, wedge-oblong, almost pinnatifid, entire toward the base, with revolute margins, green above, white with silvery wool beneath; calyx white-tomentose. — Dry barren fields, etc., N. S. to Dak. and southw. to D. C. June- Sept. (Eu.)