SAGUARO CACTUS More Life
Video: Watch creeper plants climb trees.
Quiz: Take "The World of Plants" quiz. HowStuffWorks: How Desert Survival Works. Travel through the Sonoran Desert, which stretches across large parts of the southwestern United States and northern Mexico, and you will spy a tall figure with outstretched arms — perhaps many of them. That figure is the native flower of Arizona, the saguaro cactus.
A fully developed representative has a main column, with five or so arms branching out and reaching upward. Like many of its fellow cacti, a saguaro bristles with spines on the outside. Shallow roots extend outward about as far as the cactus is tall. The roots latch on to rocks and other sturdy surfaces to protect the cactus from winds sweeping across the plain.
The saguaro can grow up to 40 feet (12 meters) and weigh in at 4,000 pounds (1,814 kilograms) or more, but a century may pass before it reaches that tremendous height and weight. Some of the biggest saguaro cacti may be as old as the United States. Growing at a snail's pace allows the stately cactus to withstand the desert's harsh conditions. So does absorbing and retaining enormous amounts of water. It also has a few tricks up its sleeve when it comes to reproduction.
SAVVY REPRODUCTION
Instead of offering its white flowers to the scorching sun, the savvy saguaro waits until nighttime, opening a few flowers at a time. During a three-week period, each cactus plant will have hundreds of flowers open, with each flower closing and dying at the end of the night. When the flowers are exposed, bats come to consume the cacti's nectar, pollinating them as the animals move from plant to plant.
The pollinated flowers develop fruit that are pregnant with seeds. The fruits' sweet, thick flesh protects the seeds from the sun, until they begin to ripen and open, creating a perfect meal for a passing dove. As you can see in Life, the dove will eat the fruit and then excrete the seeds it has consumed, leaving them essentially fertilized and ready to sprout.
In the desert though, it takes a village for reproduction to happen. Some of the saguaro's fruit fall to the ground and become meals for ants and other creatures, like tortoises. Ants will haul the seeds underground, where they are protected from the sun and may have access to water traveling to plants' root systems. Tortoises, in turn, will settle in a shady area, where they excrete the seeds in their dung, much like doves.
Still, with all that help, it's a low-percentage game. A saguaro cactus will produce millions of seeds in its lifetime, but perhaps only one will become a fully developed plant, arms outstretched under the relentless sun.
Written by Jacob Silverman, HowStuffWorks
|
advertisement
More Life
Stay Connected
Own Life
|
-
our sites
-
video
mobile
-
shop
-
stay connected
-
corporate
