Repert. Bot. Syst. 1: 118. 1842.
Plants perennial, scapose, from elongate, stout rhizomes. Leaves (15-) 25-40 (-55) × (8-) 12-20 (-35) cm; blade with 3-5 orders of leaflets and lobes; abaxial surface and sometimes adaxial surface glaucous; penultimate lobes oblong, distal ones usually coarsely 3-toothed at apex, (4-) 10-20 (-50) × (1.5-) 3-4 (-8) mm. Inflorescences paniculate, 2-30-flowered, usually exceeding leaves; bracts linear-lanceolate, 4-7 (-12) × 1-2 mm, apex acuminate. Flowers pendent; sepals lanceolate to ovate or nearly round, 2-7 × 2-3 mm; petals rose-purple, pink, cream, or pale-yellow, rarely white; outer petals (12-) 16-19 (-24) × 3-6 mm, reflexed portion 2-5 mm; inner petals (12-) 15-18 (-22) mm, blade 2-4 mm wide, claw linear-elliptic to linear-lanceolate, 7-10 (-12) × 1-2 mm, crest 1-2 mm diam., exceeding apex by 1-2 mm; filaments of each bundle connate from base to shortly below anthers except for a 2-3 mm portion of median filament just above base; nectariferous tissue borne along distinct portion of median filament; style 3-9 mm; stigma rhomboid, 2-horned. Capsules oblong, 4-5 mm diam. Seeds reniform, ca. 2 mm diam., finely reticulate, elaiosome present.
B.C., Calif., Oreg., Wash.
Subspecies 2 (2 in the flora).
Andrews has been cited almost universally as the author of Fumaria formosa. However, Haworth's authorship of the sixth volume of Andrews' Botanists' Repository (in which this species was originally described) generally has been overlooked, and it was actually Haworth who first delineated F. formosa (W. T. Stearn 1944).
Early attempts to cross Dicentra formosa with D. eximia (2n = 16) failed, possibly because the D. formosa parents were tetraploids. Several later hybrids between the two species received plant patents and have become widely marketed throughout the flora area and elsewhere (K. R. Stern 1961, 1968; K. R. Stern and M. Ownbey 1971).
Both subspecies, as well as hybrids between them and Dicentra eximia, are widely cultivated.
The Skagit used a decoction of the roots of Dicentra formosa to expel worms; they chewed raw roots for toothaches (D. E. Moerman 1986, species not indicated).