Saguaro Sentinel
The Saguaro cactus is an amazing plant. The largest cactus in the U.S., it is found only in the Sonora Desert that spreads from northern Mexico into Arizona.
A fully mature Saguaro can grow to about 80 feet in height and weigh between 6 to 8 tons. Their lifespan can be 150-200 years.
Desert Survival
The apparent barrenness of the desert is an illusion: every inch of land is accounted for. The plants use a variety of methods to survive, beginning with staking out their territory for catching rain. They can’t afford to crowd together like the vegetation in a northern forest where water is plentiful. That doesn’t mean that the desert land is empty, you just need to know where to look: under the surface.
The Saguaro, with a tap root that only goes 2-3 feet into the ground, relies on a network of shallow roots to collect water. These roots fan out from the cactus and have a length equal to the cactus’s height. The root systems of other types of plants co-mingle with those of the Saguaro or are found at different depths.
The shape of a plant is another method for capturing moisture. The Saguaro has a smooth waxy surface that is patterned with deep vertical ribs.
It is an ideal system for directing rain down into the ground and the cactus’ root network. The Saguaro draws in the water and stores it in its outer pulp which expands much like an accordion. This can increase the weight of the plant by one ton.
The cactus must be at least 60 years old and about 18 feet tall before it begins to grow its branches. Typically, these branches will outward and then up. However, freezing weather can damage the growing tip and then the branch will point downwards.
Budding Saguaro Branch
Life Cycle
- A Saguaro begins life as a seed rooted in the sheltering cover of a nursery plant, such as a Mesquite.
Until the seedling reaches a height of about one foot, which can take approximately 20 years, it is vulnerable to being eaten by desert rodents and rabbits and killed by frost and drought.
As the Saguaro grows larger it becomes less vulnerable to frost. The water in its pulpy flesh stores the heat of day and then slowly releases it at night. Birds take advantage of this solar heating by boring holes into the cactus and building nests.
- After 40-50 years, the Saguaro reaches a height of about 8 feet and begins to bloom and produce fruit.
At night in the spring, the cactus blooms produce a nectar that attracts bats.In June the fruit is ready to harvest.
The Tohono O’odham people have harvested the fruit for hundreds of years. The fruit may be eaten raw or cooked down to a sweet syrup. In addition, each fruit can have as many as 5,000 seeds that are rich in fat and protein. They can be ground down into a powder and used in cooking. (1)
Other fruit harvesters are the Gila Woodpecker, White-winged Dove, and House Finch.
- At about 65 years and a height of 18 feet, the cactus begins to grow branches.
- At approximately 85 years and a height of 23 feet, the Saguaro is a mature plant.
- Eventually the cactus succumbs to wind and storm damage, frost damage (that can take as long as 10 years to appear), bacterial rot, and old age.
Saguaro Husk
These and many other images are available for purchase as archival giclee prints or stock photo files. Go to Les-Phillip.com.
(1) Saguaro Cactus, Icon of the Sonoran Desert; Johnathan DuHamel, 06/23/2011, TucsonCitizen.com; http://tucsoncitizen.com/wryheat/2011/06/23/saguaro-cactus-icon-of-the-sonoran-desert/
See also:
SAGUARO (Carnegiea gigantea),
http://www.biology.ed.ac.uk/research/groups/jdeacon/desbiome/saguaro.htm
This is an archived page that is no longer maintained. It is still very informative.
The Edible Saguaro Cactus, Maranatha, 01/31/2009, notecook.com,
http://notecook.com/desserts/fruits/the-edible-saguaro-cactus/
Official Website of the Tohono O’odham Nation, http://www.tonation-nsn.gov/
