Aerial stems persisting for 1 year or less, with stomates on surfaces scattered or in bands on each side of valleys. Branches in regular whorls, except for unbranched forms of Equisetum fluviatile and E . palustre and brown fertile stems of dimorphic species. Cones rounded at apex.

Species 8 (6 in the flora): North America, s Central America, w South America, Europe, Asia.

SELECTED REFERENCES

Hauke, R.L. 1978. A taxonomic monograph of Equisetum subgenus Equisetum. Nova Hedwigia 30: 385--455.