One of the more painful subjects for the desert educator is the cactus. In this case, I'm not talking about the world of hurt caused by inadvertently impinging on the territory of a cactus, but the mental anguish evoked by misapplication of the name. All too many of our newcomers, and if the truth be known, a few of our oldsters, think that anything with spines is a cactus. How often have you seen a picture of an ocotillo or a yucca or an agave with a caption below indicating that it's a cactus? I can tell you too often!
A cactus is a member of a specific family of plants: the Cactaceae.
Anything else, no matter how spiny or succulent, is not a cactus. Most cacti consist
only of stems and, in season, flowers or fruit. The pads of prickly pear, the cane-like
stems of chollas, the cask-like body of the barrel cactus all are leafless stems. On
the other hand, what do you see when you look at a yucca or an agave? Nothing at all
EXCEPT leaves!
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.
This is not a cactus—in fact, not even close. This is a Blue Yucca, with a Banana Yucca peeking in on the left side. Chihuahuan Desert Gardens, photograph by A.H. Harris.