Petasites japonicus, (Siebold & Zucc.) Maxim.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1976, Flora Europaea. Volume 4. Plantaginaceae to Compositae (and Rubiaceae), Cambridge University Press : 188

9. P. japonicus (Siebold & Zucc.) Maxim. , Razb. Rukop. Sočin. F. Schmidta Reis. Amurl. 17 (1866)

( Nardosmia japonica Siebold & Zucc. ).

Leaves reniform-cordate, glabrous above, hairy beneath; basal lobes convergent, with c. 5 lateral veins bordering the sinus; margin irregularly dentate. Scapes with 15-25 scaleleaves, the lower almost cordate at the base, the middle 5-7 cm, rarely with a rudimentary lamina. Capitula c. 35. Involucre 8-10 mm; bracts pale green, sparsely pubescent, with usually entire apex; bract subtending the lowest inflorescence-branch 1 -7-4 cm wide. Florets all tubular. Stigma of male florets 1 -6-1 -8 mm. In = 84-87. Stream-banks. Locally naturalizedfrom gardens in N. W. & C. Europe. [Br Cz Da Ho.] (Japan, Sakhalin.)

Only the male plant is naturalized in Europe.