The Sonora desert of America is best known in the world for Saguaro cactus (Cereus Giganteus) which is one of the largest specie of cactus on earth. Although its geographical area is not too large yet it is grown in abundance like a thick forest in its range. It can be commonly seen in the Arizona Upland subdivision of the Sonoran Desert, around Tucson and Phoenix. The rainy climate of this area really supports for its enormous growth as it needs huge amount of water. Saguaro cactus is the most prominent plant due to its unique shape and massive size but this area is also center of dense plantation due to fair rainfall. Most of the Saguaro cactus trees are surrounded by other desert trees and shrubs.
Saguaro cactus can grow up to 12 meters in height and its approximate is age is more than 200 years. A young Saguaro cactus grows very slowly and they are protected by the ‘nurse plants’ from animal and severe solar effects. In fact their shadows work like shelter and generate a humid and moisture absorbent atmosphere for their development.
The trunk surface of Saguaro cactus consists of a protective layer of succulent and an obtrusive hairy skin which store water. There also large thrones on the branches of the trunk that arise from each areole. In the flowery season bell shaped flowers are bloomed having almost 10 Cm width. They attract birds and bees towards themselves and after pollination the succulent fruit is produced containing of juicy pulp and numerous black seeds. The birds are the main source for the dispersal of these seeds on the supporting plants. The bees also play very important role in depositing of the seeds who visit due to the scent and copious nectar of Saguaro cactus flowers.
Saguaro cactus is housing scheme of many birds and animals. Gila woodpecker and gilded flicker are specially known with Saguaro cactus that creates nesting holes in their stems. The hawks also make their big nests on the branches of Saguaro cactus. The Saguaro cactus ideally grows in moist conditions and commercially grown in many nurseries by creating artificial cacti atmosphere. The Saguaro cactus is normally threatened with weather effects like wind, fire by lightning, freezing in winter and storms.