Golden rat tail cactus (Cleistocactus winteri) in the world deserts environment within the Conservatory at the United States Botanic Garden (1867).

100 Maryland Avenue SW, Washington, District of Columbia: 29 January 2014

part of the United States Botanic Garden album

Of all the diverse botanical species on exhibit at the United States Botanic Garden Conservatory, I found these Cleistocactus winteri native to Bolivia to be one of the most unusual and visually interesting.

A member of the Cactaceae (cactus) family, Cleistocactus winteri is classified as endangered by the International Union for Conservation of Nature.

Cleistocactus winteri is only known to exist in two locations — a combined area of 96.53 square miles — within the Province of Florida. They occur on forest cliffs in seasonally dry inter-Andean valleys at elevations around 4,400 feet.

The northern subspecies is only found on a single cliff, while the southern subspecies occurs over a six mile or so stretch of cliffs. The latter is also subject to frequent collection by locals who in turn use them as ornamental plants.

There is no shortage of interesting and free things to do in the District, but I definitely recommend visiting the United States Botanic Garden. Open daily from 1000 to 1700, the various themed areas like the world deserts environment can provide a nice change of pace… especially during a wintertime trip.