July 2007 Next to the giant saguaro, the many bizarre forms of cholla cacti are some of the most distinctive wild plants of the Sonoran desert. Of more than thirty species of cholla that grow throughout Arizona, three are common in the Deem Hills Mountain Preserve that overlook the neighborhood of Stetson Hills.
Perhaps the most well-known is the fuzzy looking teddy bear cholla (Opuntia bigelovii), also called silver cholla for the way its blonde spines shine when backlit by morning or evening sun. The loosely attached joints or “balls” easily hitch onto unwary wild animals and humans. Interestingly, packrats seem immune to the barbed spines of the teddy bear cholla and will pile the balls at the entrance to their dens to deter predators such as fox and coyotes. Many birds, most notably the cactus wren, are also able to defy the barbs and find well-armed protection for their nests in the branches of the teddy bear and other chollas. A comb is a good tool to keep in your purse or pack whenever walking in the desert. If a cholla ball “jumps” onto you, just pry it off with the comb! NEVER touch or kick a cholla ball! Look for the bright red, spineless, berry-like fruit of the desert Christmas cactus (Opuntia leptocaulis) sprawling in the shade of leafy shrubs or trees. The slender stems of this cholla are only 1/8-1/4 inch in diameter, making the half-inch long spines look very fierce in comparison. The stems of pencil cholla (Opuntia arbuscula) are also very slender but about twice as thick as the Christmas cactus, and have drab greenish fruit. Buckhorn cholla (Opuntia acanthocarpa) is the most common of the three species found in Deem Hills and is named for branches that sort of resemble deer antlers. The flowers of buckhorn vary from bronze to pale yellow to reddish. Flower buds of the buckhorn were once a major source of food for native peoples of the area and were gathered every spring, then roasted and dried for storage to be used throughout the year for soups and stews. The fruits of chollas can also be eaten, but have not been as popular as the flower buds because they are so spiny. Cholla fruits and buds are also important food for many other desert dwellers, such as tortoise, javelina, packrats, birds and jackrabbits. Chollas are closely related to prickly pear cacti, but have cylindrical stems rather than flat pads. Like prickly pears, chollas easily reproduce new plants when pieces of stems or fruit break off and grow roots. If you want to grow a locally native cholla in your home landscape, just choose your favorite cholla and carefully transplant a piece to your yard. They are easy to grow and need only lots of sun and what little water falls from the sky to thrive.
Since May 2005, I have written a natural history column for a neighborhood newsletter published by Jennifer Moore called "Our Big Backyard: Natural History of the Deem Hills," and since 2010, "A Suburban Naturalist."All of these columns are reproduced here. Deem Hills is a City of Phoenix Desert Preserve located just north of Happy Valley Road in north central Phoenix, and just west of I-17. The Preserve and adjacent hills comprise over 900 acres of open space with several miles of hiking trails. For more perspectives from the Deem Hills and suburban Phoenix, also check out my companion blog, Kat Tracks.
As a naturalist with a special interest in botany and plant ecology, some of my greatest passions are to explore, photograph and write about native plants. If I can spark an awareness or interest in natural history in others along the way, that is my greatest reward.