Horsetails (Class Equisetopsida) are plants that superficially resemble a horse’s tail. Horsetails have segmented stems with extremely reduced leaves typically appearing non-existent. When present, the leaves grow in whorls radiating from the node sheaths of the jointed stem, resembling spokes of a bicycle wheel. When present horsetail leaves have branched venation, indicating that their leaves are actually reduced megaphylls more closely resembling true ferns than whisk ferns. Horsetails’ life cycle is an alternation of generations, and spores are borne in a cone-like structure at the tips of the stems, called a strobilus.
