Horsetails are easily recognized ancient plants, the only remaining ones of their kind from millions of years ago. They are fern-like in function but not fern-like in shape. They are consumed by all kind of widllife, including mammals. Two varieties of the Equisetum exist in Florida (Wunderlin, 2003). Horsetails occur throughout the entire U.S. and the majority of Canada (Kartesz, 1999).
Scouring-rush horsetail is a horsetail. Stems erect, 2-5 ft. tall, ridged, dark evergreen, jointed nodes, conspicuous blackish rings around the nodes, hollow between nodes; leaves reduced to very small node-scales; cone-like structure at stem tip is called a "strobilus", to 1 in. long; strobili contain sporangia which produce green reproductive spores, strobili are various shades of brown.