What is the Joshua tree?
The Joshua tree is a desert tree that grows in southwestern North America, in California, Arizona, Utah, and Nevada. A native of the Mojave Desert, these drought-tolerant trees thrive in the open grasslands of California's Joshua Tree National Park. The Mormon pioneers named this tree after the prophet Joshua, because its extended branches resembled the outstretched arm of Joshua as he pointed with his spear to the ancient city of Ai. The trees are twisted and spiky, with tough leaves, and look a little bit like a tree from a Dr. Seuss book. Joshua trees can grow from seed or from an underground rhizome of another Joshua tree. They grow very slowly, sometimes 3.9 to 7.8 inches (10 to 20 centimeters) in their first few years. The tallest trees reach about 49 feet (15 meters) tall. The trunk of a Joshua tree is made of thousands of small fibers and does not have yearly growth rings, which makes it hard for scientists to tell the tree's age. Although the fragile tree has shallow roots, if it survives the harsh desert environment, it can live hundredseven thousandsof years.