The primary industry of the California desert is weirdness. This area generates more per-capita weirdness than anywhere else in America, beginning with the Joshua tree. (Of course, it helps that there are so few capitas residing there.)
The Joshua tree acquired its name because early religious pioneers think it looked like Joshua holding up his arms to stop the sun from setting. Personally, I believe that those early religious pioneers were a little too affected by the sun. When fully mature, the tree is branched like a common or garden variety tree, but covered in short cactus-ish spines instead of twigs and leafs. Joshua Tree National Park has, logically, the largest concentration of Joshua trees in the world. It's also well known for three other things: high quality rock climbing, an abrupt transition between high desert and low desert, and...well, read on.