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 ...