Pachycereus pringlei

Pachycereus pringlei (also known as Mexican giant cardon or elephant cactus) is a species of large cactus native to northwestern Mexico, in the states of Baja California, Baja California Sur, and Sonora. It is commonly known as cardón, a name derived from the Spanish word cardo, meaning "thistle"; additionally, it is often referred to as sabueso (or "bloodhound"), which is possibly an early Spanish colonialist interpretation of the Seri word for the plant, xaasj.

Large stands of this cactus still exist, but many have been destroyed as land has been cleared for cultivation in Sonora.

Climate change will likely affect the future distribution of numerous plant species, including Pachycereus pringlei, which can be attributed to alterations in precipitation and temperature.

The cactus fruits were always an important food for the Seri people, in Sonora; the dried cactus columns themselves could be used for construction purposes, as well as for firewood.

The cactus thrives in barren landscapes thanks to a remarkable symbiotic relationship with a biofilm that forms on its roots. This biofilm enables the cactus to colonize bare rock, even in the absence of soil. This makes this species an opportunistic lithophyte. The root's bacterial colonies can fix nitrogen from the air and break down the rock to expose hidden sources of nutrients. The cactus has evolved to maintain cultures of the symbiotic bacteria within its dormant seeds.