Class Equisetopsida C.Agardh (1825) - horsetails see Subclass Equisetidae Warm. (1883)
   gymnosperms see Class Spermatopsida
     Subclass Pinidae Cronquist, Takht. & Zimmerm. (1966) - conifers
       Order Cupressales Link (1829)
         Family Cupressaceae Gray (1822), nom. cons. - cypress family
           Genus Sequoiadendron J.Buchholz (1939), nom. cons. prop.