Tiarella unifoliata Hooker, Fl. Bor.-Amer. 1: 238, plate 81. 1832; T. trifoliata subsp. unifoliata (Hooker) P. M. Kern

Basal leaves usually simple; blade 2-9 × 3-10 cm; leaflets sessile, deeply to shallowly lobed. Cauline leaves rarely 3-foliolate; blade 2 × 3 cm; leaflet lobes ca. 1/2 length of leaflet, distal segments laciniate. 2n = 14.

Flowering Jun-Sep. Moist, dense woods; 300-1900 m; Alta., B.C.; Alaska, Calif., Idaho, Mont., Oreg., Wash.

Variety unifoliata is relatively uniform throughout its range. Locally in Alberta, it grades into a more deeply lobed leaf form.