These don't grow just anywhere in the desert, you know. Those iconic cactuses that you see in the cartoons? They're Saguaros, and they grow in the Sonoran Desert. We passed through part of this desert north and west of Phoenix.
These are at a rest stop west of Phoenix.
Supposedly they can take up to 75 years to grow any side arms.
They sometimes are lined up on a ridge of a mountain, but I didn't get any pictures of that (cloudy weather, plus I did most of the driving through Saguaro country).