In the molecular phylogenetic classification of Smith et al. in 2006, Equisetales, in its present circumscription, was held to be the sole member of class Equisetopsida. The linear sequence of Christenhusz et al. (2011), intended for compatibility with the classification of Chase and Reveal (2009) which placed all land plants in Equisetopsida, made it the sole member of subclass Equisetidae, equivalent to Smith's Equisetopsida. The placement of Equisetales in subclass Equisetidae has subsequently been followed in the classifications of Christenhusz and Chase (2014) and PPG I (2016).
^The Pteridophyte Phylogeny Group (November 2016). "A community-derived classification for extant lycophytes and ferns". Journal of Systematics and Evolution. 54 (6): 563-603. doi:10.1111/jse.12229.
^Stanich, Nicholas; Gar W. Rothwell; Ruth A. Stockey (2009). "Phylogenetic diversification of Equisetum (Equisetales) inferrred from Lower Cretaceous species of British Columbia, Canada". American Journal of Botany. 96 (7): 1289-1299. doi:10.3732/ajb.0800381. PMID21628278.