Bushy Cinquefoil
Potentilla paradoxa Nutt. ex Torr. & Gray

 

Erect to decumbent, taprooted annual or shortlived perennial 1.5-7 cm tall, glabrous below to hirsute above; stems simple or branched from the base, diffusely branched above. Leaves mostly cauline, long-petioled below, shorter petioled above, pinnately compound, with 7-11 leaflets, the smaller, sessile bractlike leaves of the inflorescence mostly ternate; leaflets elliptic to obovate, 0.8-4 cm long, 0.5-2 cm wide, serrate; stipules prominent, ovate, entire to serrate, mostly 0.5-1.5 cm long. Flowers usually numerous in open to dense cymes, not showy; sepals ovate-triangular, acute to abruptly acuminate, 2.5-4 mm long, the bractlets sometimes longer; petals yellow, obovate, 2.5-3.5 mm long, about equaling the sepals; stamens (10-15)20; styles terminal. Achenes brownish, obliquely obovate, ca. 1 mm long, apically ridged, often corky-thickened in the lower half. Jun--Sep. Shores, ditches, floodplains and flats, often where sandy or gravelly; frequent;