Equisetum bogotense

Equisetum bogotense, the Andean horsetail, is a herbaceous perennial that reproduces through spores. It has thicker less bushy whorled branches, and a silica rich rhizomatous stem, which roots grow out of, under ground. This stem is a dull dark brown color with glabrous growth aside from the sheathed segments. The plant has a history as a traditional herbal remedy, and a study of its diuretic effects on humans showed significant increases in urinary sodium, potassium, and chloride. Human and animal trials of indicate that "E. bogotense" has "high" efficacy as a diuretic. It is used in several modern herbal supplements. The species epithet refers to Bogotá, the capital of Colombia.
A segregate species, "Equisetum rinihuense", has been described.
According to a recent study, this species may be the most isolated of all the genus, being more closely related with fossil Equisetums rather than living ones .