The Ferocactus emoryi, also known as the Coville Barrel Cactus, is a fascinating desert cactus and a member of the Ferocactus genus. Native to the southwestern United States and northern Mexico (Baja California Sur), it is also known as Ferocactus covillei, Traveler's friend, and Emory's barrel cactus. Mature plants are typically less than six feet tall and more cylindrical than barrel-shaped. The Ferocactus emoryi is covered in sharp central spines that help protect it from predators and harsh environmental conditions.

The solitary barrel cactus of the Ferocactus emoryi is well-adapted to survive in arid environments. It has the ability to store water in its thick, fleshy stem, allowing it to withstand long periods of drought. In terms of care, it's important to avoid overwatering, as the wet cactus can lead to root rot. The ribbed texture of the stem helps it expand and contract as it absorbs and retains water.

The Coville Barrel Cactus is a slow-growing plant that requires well-draining soil and plenty of full sunlight or partial shade to thrive. It's also advisable to provide some shade during the hottest part of the day, especially in regions with scorching temperatures. This Ferocactus emoryi tolerates sporadic light frost in USDA zones 9–10 but should be protected below 50°F and 20°F, as temperatures below 20°F can cause damage or death.

The flowers of the Ferocactus emoryi typically bloom in the spring or summer and can range in color from bright yellow to orange. Ferocactus emoryi produces nectar in the nectaries at the top of the cactus that feed the ants that live around its base. In turn, the ants are very territorial and appear to protect the plants from other insects that might try to walk up the stem and damage the fresh, delicate cells at the growing apex or steal nectar or pollen from the flowers.

This strategy is useful not only to protect the plant from small herbivores but also to promote outcrossing pollination because the only bugs that can successfully visit the flowers without being attacked by the ants are flying pollinator insects like butterflies and bees that carry pollen from other individuals and other populations, in turn increasing the genetic diversity of the species. The Seri people of Sonora use Ferocactus emoryi for food, medicine, cultivation, and pollination.

To propagate your Ferocactus emoryi, harvest seeds from mature fruit and plant them in well-draining soil. Take stem cuttings from the mother plant, let it dry, callus, and root. Both methods require patience and care but can successfully expand your cactus family. Give this Ferocactus emoryi a try if you're looking for an easy cactus plant to care for!