Something a little different, a Crested Saguaro in the Tonto National Forest

A little bit about the Crested Saguaro from amusingplanet.com:

The saguaro cactus is composed of a tall, thick, fluted, columnar stem about two feet in diameter with several large arms that curve upward in the most distinctive conformation of all Southwestern cacti. But sometimes they produce a fan-shaped form of uncontrolled growth at the tip. These odd growths are referred to as cresting (or cristate), and are very rare occurrences. It is estimated that this condition affects approximately one out of every 200,000 saguaros. Originally, less than 200 of these abnormalities were thought to be in existence. However, more than 2,000 have been discovered so far, and biologists believe that there may be many more.

The cause of cresting, also know as fasciation, in saguaro is not fully understood. Some speculate that it is a genetic mutation, or caused by micro-organisms, or physical damage such as lightning strike or freezing.