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Related to Equisetum: Equisetum arvense
Equisetumany pteridophyte plant of the genus Equisetum, comprising the horsetails. The plant is herbaceous, has rhizomes and a vertical stem with whorls of scale leaves, and is often found growing in water and damp conditions. It is the last living representative of the order Equisetales, members of which, during the time of the dinosaurs, grew as high as trees and were probably a major food source.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005