The saguaro cactus is the iconic cactus of Arizona. They are columnar cactus that can grow multiple branches referred to as arms. They have a long lifespan, with some living more than 200 years. Their growth depends on rainfall, which they gather with their root systems that can extend as far as 100 feet. The water is stored in ribs of wood that form the skeleton of the cactus. As a result, a fully grown cactus can weigh up to 4,800 pounds. Saguaros grow arms to increase their ability to reproduce as their flowers only grow at the end of an arm. Oddly, the flowers aren’t pollinated by insects or birds but by the lesser long-nosed bat.