The Sonoran Desert is an arid region covering approximately 100,000 square miles in southwestern Arizona and southeastern California, as well as most of Baja California and the western half of the state of Sonora, Mexico. Subdivisions of this hot, dry region include the Colorado and Yuma deserts. Irrigation has produced many fertile agricultural areas, including the Coachella and Imperial valleys of California. Warm winters attract tourists to Sonora Desert resorts in Palm Springs, California, and Tucson and Phoenix, Arizona.
Prickly pear cactus are found in all of the deserts of the American Southwest, with different species having adapted to different locale and elevation ranges. Most require course, well-drained soil in dry, rocky flats or slopes. But some prefer mountain pinyon/juniper forests, while others require steep, rocky slopes in mountain foothills.
Like other cactus, most prickly pears and chollas have large spines — actually modified leaves — growing from tubercles — small, wart-like projections — on their stems. But members of the Opuntia genus are unique because of their clusters of fine, tiny, barbed spines called glochids. Found just above the cluster of regular spines, glochids are yellow or red in color and detach easily from the pads. Glochids are often difficult to see and more difficult to remove, once lodged in the skin.
The trip across Arizona is just one oasis after another. You can just throw anything out and it will grow there, I like Arizona.
Crash landed on Earth, an alien stepped out onto an arid, rocky bajada and found himself dwarfed by gigantic, grotesque, green figures with arms reaching toward the sky. Feeling at home in this weird landscape, he approached one fiercely armoured mammoth, which he estimated to be 35 feet tall and weighing several tons. “Where am I on your planet?” he questioned the giant. The strange green figure remained silent.
Where was the alien? By the distinctive characteristics of the peculiarly human-like plant, he could have only been in the Sonoran Desert. His geographical location could be pinpointed to be either in extreme southeastern California near the Colorado River, in southern and western Arizona, or south of the border in northwestern Mexico. These are the only places on earth where the saguaro cactus — grand symbol of the Sonoran Desert, the West and arguably the United States — grows.
If the stately 20-to 50-foot saguaro could have talked to the alien, it would have had tales of the Old West to tell. Some have been around since Teddy Roosevelt became president in 1901. A few still living today were tiny young upstarts, perhaps growing under the shelter of a paloverde tree, when Thomas Jefferson was elected President in 1801.
The saguaro can grow only in narrow environmental niches within the Sonoran Desert, usually below elevations of 3,500 feet. Freezing temperatures and frosts can kill or damage the delicate plant. Wild arms and drooping limbs may indicate that a particular plant survived a bitter winter.
These distinctive human-like arms begin to grow only in middle age, about 75 years, after achieving a height of 14 to 16 feet. The oldest, with dozens or more branches, have marked the passage of many years.
When the pleats are more deeply shadowed, more defined, drought has shaped the cactus. The plant can lose up to 82 percent of its moisture before it dies of dehydration. In times of little rain, shallow roots near the soil’s surface can capture the moisture of even the lightest rainfall. The downward-pointing spines, “drip tips,” also help by directing rainwater toward the base of the plant. These clusters of spines also play a role in cooling the outer skin; they help deflect wind and provide insulation from freezing as well.
Another feature of the saguaro, the many holes on its body, makes one wonder if the Gila woodpeckers inflict much damage as they hammer into the tissues used to store water. Often, these meticulous birds drill 2 or 3 holes before they are satisfied. But the plant quickly minimizes damage by sealing off the wound with callous scar tissue to stop water loss. Conserving water loss is essential to the survival of the saguaro. When the sun beats unmercifully on its waxy, watertight, outer surfaces, microscopic pores close. At night, when temperatures are lower, the pores open, allowing for the entry of carbon dioxide, necessary for photosynthesis and the manufacture of carbohydrates.
“Even the plants in Arizona wanted to hurt you.”
Author: Janette Rallison
“He’d always had a quickening of the heart when he crossed into Arizona and beheld the cactus country. This was as the desert should be, this was the desert of the picture books, with the land unrolled to the farthest distant horizon hills, with saguaro standing sentinel in their strange chessboard pattern, towering supinely above the fans of ocotillo and brushy mesquite.”
Author: Dorothy B. Hughes
“If you don’t die of thirst, there are blessings in the desert. You can be pulled into limitlessness, which we all yearn for, or you can do the beauty of minutiae, the scrimshaw of tiny and precise. The sky is your ocean, and the crystal silence will uplift you like great gospel music, or Neil Young.”
Land of extremes. Land of contrasts. Land of surprises. Land of contradictions…. That is Arizona.
~Federal Writers Project, Arizona: The Grand Canyon State, 1956
I live in the dry dusty desert
Where we’re always short on water
And even if the sun fell upon us
It couldn’t get any hotter.