The Joshua Tree Belongs to the Agave Family

The Joshua tree looks like a tree drawn from memory by someone who had never seen one. Botanically it is something else. The U.S. National Park Service states that the Joshua tree, Yucca brevifolia, was once classified as a giant lily, and that modern DNA research has placed it in the Agave family. Like the California fan palm, it is a monocot, part of the same botanical group that includes grasses and orchids. The name has a story. In the mid-19th century, Mormon settlers gave the tree its common name, believing its outstretched branches resembled the biblical Joshua guiding them westward. Joshua trees grow slowly, at about half an inch to 3 inches per year. The tallest in the park stretch over 40 feet, and the average lifespan is thought to be around 150 years.