Silver Cholla Cactus

Cholla cactus grows numerous spines to protect it from being eaten and to save water in the arid desert.

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The adaptive cholla cactus (Opuntia acanthocarpa) offers limited access to those that come near to it. Horses, coyotes, burros and yes, even people, all must remain wary of the sharp, penetrating spines of the cholla. The jointed offshoots bear formidable spines and, once attached, tiny barbs along each spine secure that segment of cactus to its host. The piece breaks off rather easily and with spines this sharp, it occasionally goes unnoticed until the unlucky individual lies down or leans up against something.

This is one way that the clever cactus reproduces; the segments that attach to a host are carried away. When the segments fall to the ground they may take root and grow to become the next generation of cholla. Alternatively, the fruits at the end of the limbs are often free of spines and encourage locals such as coyotes and bighorn sheep to nibble the sweet flesh. Hidden within the fruit are the seeds of the cholla. These seeds pass through the animal and can be distributed in its scat. This benefits both cactus and animal as the animal gets a tasty meal and the cactus gets to spread its seeds. Other animals, like pack rats, also benefit from chollas as they will often use the perfectly perforated skeleton of dead cholla branches as shelter.