Epiphytic cacti do not live in soil like other cacti but in places like rain forests they inhabit the forks or large branches of trees, their roots clinging tightly to their host. Epiphytes have specially designed stomata (leaf openings), that help absorb moisture from the open air.

One of the larger genera in the Cactus family, and one of the most variable. This month we will show off our collections of Mammillaria straight spined clusters.

Columnar cacti are not a closely related set of genera, but a lumping together of all the cacti that are much longer than they are around.