Equisetum bogotense (Andean horsetail)

Native to tropical and southern South America, this perennial horsetail spreads through underground rhizomes in wet soil. Its slender green stems have distinct joints and whorls of fine side branches. Tiny leaves form toothed sheaths around the nodes, while the green stems carry out photosynthesis. It reproduces through spores in small cones at the stem tips rather than through flowers and seeds. In Colombia, it occurs between about 4,920 and 12,470 feet. It is used in traditional medicine. Photographed in Bogotá, Colombia.