Maguey sierra negra is a wild Agave americana. It takes up to 25 years to mature. Today, mezcal made with Maguey sierra negra is quite rare. It was widely cultivated many years ago but due to over-production and long times to mature it has been mostly abandoned. Depending on the region, the term sierra negra may actually be referring to Maguey arroqueno, which is very similar in size, shape, and character.