The 'Ponytail Palm' is not a palm, but a caudiciform from Mexico. Develops a thick caudex and unusual thin trunks with graceful, grassy tops. Commonly used in landscape across the warm parts of the U.S. and as an interiorscape plant in cool climates. Can grow very large in time, but tends to remain stunted to the pot size provided. The caudex is naturally exposed and grows throughout the life of the plant, which apparently can be centuries, reaching huge proportions.