653 Polygonum bistorta L.

This polymorphic species is widely distributed in Eurasia and northwestern N. America:. Among the lower taxa subsp. plumosum (Small) Hult. in E. Siberia and northwestern N. America is mapped separately. Its distribution in Siberia is, however, insufficiently known. The European taxon has been introduced into Ireland and Scandinavia and other countries in and outside Europe, also into N. America (not marked on the map). Cf. also Meusel et al. 1965, map p. 130.