If you've ever seen an old-fashioned Western, you've seen a saguaro. Saguaros are very tall, tree-like cacti which have become famous icons on the American West, although they are in fact native specifically to the Southwest, with saguaro habitat stretching into Mexico. These extremely tall cacti are a familiar feature of the landscape of the Sonora Desert, and their fruit has been used by Native Americans in the area for centuries.
These cacti have a very slow growth habit, and they can live to be up to 200 years old, and sometimes even older. Saguaro cacti have woody skeletons which support a fleshy, succulent cortex covered in spines. Like other succulents and cacti, the saguaro can store water for an extended period of time, and it has a very shallow, broad root network which is designed to collect as many nutrients as possible for the parent plant. Often the cacti grow together in sprawled groups known colloquially as forests.
It can take up to 75 years for a saguaro to develop a single arm, with few specimens having more than five arms. In some cases, something goes wrong with the growth of the cactus, and the cactus develops a crest, rather than a set of arms. Whether crested or armed, the saguaro blooms in May to June, producing tubular white flowers which bloom at night and close up in the late morning. Once fertilized, the blooms develop into fleshy edible red fruits.
The saguaro is the largest cactus in the United States, and it once covered extensive regions of the American Southwest. Today, these cacti are harder to find, and concerns about the longevity of Carnegia Gigantea, as the saguaro is formally known, have been raised. Many saguaro forests were plowed under to make room for structures or livestock before people realized how long it took for the cacti to grow. Several regions in the Southwest including Saguaro National Park have been set aside for the protection of the saguaro and the desert habitat.
Several animals use the saguaro for shelter and habitat, with some birds actually nesting in the cacti, despite the thorns. The cacti in turn rely on creatures like bats to pollinate their flowers, as they are not self-fertilizing.