14 Equisetum scirpoides Michx

This distinct, although sometimes not clearly identified species occurs in the arctic and boreal regions of Eurasia and N. America. The distribution, especially in the C. and E. Asiatic area, should be better verified. There may, however, be a gap in central Siberia. The species belongs to the circumpolar plants (Hultén, Circumpol. I, p. 36 and map 30).