Joshua trees are the icons of the Mohave Desert just as the saguaro cactus is the icon of the Sonoran Desert. These icons meet in Northern Arizona.
Joshua trees are actually yuccas (Yucca brevifolia). When mature, Joshua trees usually range from 15 to 30 feet high (although some up to 70 feet are reported by the U.S. Forest Service). Tough leaves, which bear small, sharp teeth on their edges, cluster at the ends of branches. Joshua trees occur between 2,000-6,000 feet in northwestern Arizona, southeastern California, southern Nevada, and southwestern Utah.
Greenish white flowers occur in clusters on a short stalk. They bloom in late winter. The flowers are pollinated by the pronuba moth. The moth and Joshua tree have a symbiotic relationship.
As described by the Arizona- Sonora Desert Museum:
The moth first visits a mature flower and climbs up the stamen collecting pollen and working it into a tiny ball. This activity is repeated several times until the ball contains enough pollen to pollinate several flowers. The moth then visits other flowers and inserts here ovipositor, a long, thread-like apparatus with a sharp point, straight through the wall of the pistil and lays an egg. After the egg is laid, she carefully pulls out her ovipositor and climbs up to the stigma where she deposits some of the pollen from the ball she was carrying. The moth larvae feed on some of the developing seeds, but most seeds mature and are dispersed…”
Fruit, which is about the same color as the flower, are two to four inches long, and two inches in diameter. With age, they become spongy and dry.
The U.S. Forest Service reports:
Native people of the Mojave Desert used Joshua tree for food and in construction. Cahuilla people of southern California used Joshua tree fibers to make sandals and nets and consumed Joshua tree blossoms [8]. Red Joshua tree rootlets were utilized as a dye for baskets and blankets [2,55], and sweet Joshua tree flowers were roasted and eaten by Native people [55]. Joshua tree seeds were eaten raw or ground into a mash and cooked by southern California Natives.
Many birds, mammals, reptiles, and insects depend on the Joshua tree for food and shelter. See more information from Joshua Tree National Park.
The best place to see Joshua trees in Arizona (other than at the Arizona-Sonora Desert Museum) is along highway 93 between Wickenburg and Wikieup. That is where the Sonoran Desert meets the Mohave Desert.
For more article on desert plants see:
Agaves provide food, fiber and adult beverages
Ocotillo – an aide to hummingbirds and geologists
Chiltepin peppers, spice and medicine
Saguaro Cactus Icon of the Sonoran Desert
Yuccas provide food, fiber, and soap
The Jojoba bush and its valuable oil
Mesquite trees provide food, fuel, medicine, and more
Cactus water will make you sick
Palo Verde trees about to turn the desert golden