The Joshua tree is a distinctive desert plant. It has adapted to survive in the desert by gathering water in its leaves and by putting out an extensive root system to capture the little moisture that falls to the ground. These trees prefer coarse-textured gravelly soil that is 0.5-1 meter deep. Joshua trees are related to the yucca. The yucca moth is dependant on the Joshua tree for the habitat it provides for the newborn moths. The fibers of the Joshua trees were used to make twine by Native Americans. Twine specimens 2000 years old have been reported. The tree grows as a single stalk until it gets damaged. Where it is damaged, it branches. The older trees often have many confused-looking branches. Joshua trees spread by rhizome growth or by seed transport.