What are horsetails?

(1) Horsetails are represented by a single genus Equisetum.
(2) It is a fern in which the plant body has a underground rhizome that bears aerial green stems. It makes this plant to bear a fanciful resemblance to a horsetail.
(3) Leaves are small, scale like and form whorls at no,des.
(4) Leaves bear strobili at the tips of stems that produce spores. On germination spores produce gametophyte.