Equisetum" × "schaffneri is a horsetail (family Equisetaceae) which is believed to be an ancient, naturally occurring, widely distributed hybrid between "Equisetum giganteum" and "Equisetum myriochaetum", all from the Neotropics. At each node there are as many as nineteen branchlets, each curving downward and then upward, and up to 18 inches (45 cm) in length.
For a long time it was widely accepted that E. schaffneri had culms up to four inches (ten cm) thick, but Dr. Richard L. Hauks and Chad Husby have shown that these reports were based on a misplaced decimal point, and the true diameter of the culm is one-half inch (one cm).