By Contributing Writer
RJ Brenner
If you read my post last week , you’ll remember that I’m an avid hiker and wrote about hitting Tucson’s trails to enjoy the peak blooms of wildflower season. This week, my sights are set on the mighty Saguaro cactus. If you didn’t already know, the Sonoran Desert is the only place in the world these giants grow.

I relocated to Tucson eight years ago for a job at the Arizona-Sonora Desert Museum and immersed myself in the Natural History of the Sonoran Desert 101 — and learned that saguaros don’t get arms until they are about 70 years old. While that’s not news to most Tucsonans, my curiosity about saguaros surged from day one.

Have you ever wondered, why trees have limbs or branches, but saguaros have arms? And speaking of arms, you’ve probably noticed that most saguaro arms grow off the central trunk. That launched my search for saguaros with arms growing from arms. Why is that a rarer occurrence? No one seems to know. As I discovered, there are a great many unanswered questions about saguaros.