By Steve Velasquez
Many people consider the saguaro cactus an icon of the Southwest, but did you know saguaros grow only in the Sonoran Desert?
The Sonoran Desert region covers 120,000 square miles in southwestern Arizona, southeastern California, Baja California and the western half of the state of Sonora, Mexico.
In Tucson, the federal government maintains Saguaro National Park in two districts on the east and west sides of the city. The preserves include more than 165 miles of hiking trails.
The saguaro grows between 1 and 1½ inches in the first eight years of its life, according to the National Park Service Web site, www.npa.gov/sagu. Growth rates depend on climate, precipitation and location.
Young saguaro cacti are usually sheltered by a “nurse tree,” most often a palo verde, mesquite or ironwood.
When the saguaro reaches age 35, it begins to produce flowers. The saguaro blossom is the state flower of Arizona.
Arms usually begin to appear when a saguaro is 50 to 70 years old. In areas of lower precipitation, it may take 100 years before arms appear.
A saguaro is considered to be an adult cactus at about 125 years of age. It may weigh six tons or more, with the weight consisting mostly of water.
The cactus can grow as tall as 50 feet. It is supported by a circular skeleton of inter-connected woody ribs.
The gilded flicker and gila woodpecker make holes to live in nests inside the saguaro. After the nests are abandoned, screech owls, elf owls, purple martins, finches and sparrows may move in.
The lifespan of a saguaro averages 150 to 175 years. Some plants live more than 200 years.