Saguaro National Park, AZ
In our travels about the parks and their many green spaces, Terry and I have long marveled at what has been described as the signature plant and universal symbol of the American Southwest – the Saguaro Cactus. Pronounced Sa-WAH-roh, its scientific name Carnegiea gigantic, was given in honor of industrialist Andrew Carnegie, who’s Carnegie Institution established the Desert Botanical Laboratory in Tucson, Arizona in 1903.
Saguaros grow only in the Sonoran Desert at elevations between sea level and 4000 feet. Slow growing, the saguaro will measure a mere inch to an inch and a half in its first 8 years of growth! The tallest of saguaros reached 78 feet; however, it has since fallen to earth. An average saguaro will reach 30 feet tall and sprout 5 arms.
A marvelous display of these cacti can be found within the green spaces of Saguaro National Park just outside Tucson, AZ. Saguaro National Park is divided into two districts – Saguaro West-Tucson Mountain District and Saguaro East – Rincon Mountain District. The Eastern section of the Rincon Mountains hosts 128 miles of trails that wind through the desert and up into the mountain region. This is where Terry and I began exploring Saguaro and its desert plant life.
Each Spring after a saguaro reaches 35 years of age, the cactus will produce a creamy white flower that blooms at night and closes up the following afternoon. As many as 100 flowers may sprout from the saguaro producing tens of thousands of seeds over the lifetime of the cactus. The saguaro’s bloom is Arizona’s State flower and if pollinated during the time it is open, it will produce a red fruit. The fruit is an excellent source of food for desert wildlife and has been harvested by the Tohono O’odham Indians for thousands of years.
The “arms” of a saguaro will not appear until it reaches an age of 50 to 70 years; however, some saguaros never do produce arms. As for lifespan, these symbols of the southwestern Sonoran desert will live to 150-175 years.
Thriving in the desert requires an intricate network of roots that are capable of swallowing up vast amounts of water whenever the desert yields its scant amounts of precipitation. The saguaro’s root system lies only 3 inches below the surface and extends out as far from the main trunk as the cactus is tall. The root network is capable of soaking up as much as 200 gallons of water during a single downpour – enough water to sustain the plant for an entire year! Just one good drenching a year is all they ask!
- John Binkele