A Saguaro cactus (Carnegiea gigantea) stands silhouetted against a stormy sunset within the 57,930 acre Saguaro National Park in Arizona. Composed of 85% water, these 50-foot-tall giants can weigh over 8 tons and are the largest member of the cactus family in the United States. Their skin is smooth and waxy with stout, 2-inch spines clustered on their ribs. The outer pulp can expand like an accordion when water is absorbed, increasing the diameter of the stem and raising its weight by up to a ton.
The Saguaro generally takes 47 to 67 years to attain a height of 6 feet, and can live for 150 – 200 years. During that lifetime, a single cactus will produce 40 million seeds; however, in its harsh native environment, only one of these seeds will survive to replace the parent plant. Indeed, young Saguaro’s must start life under a tree or shrub to prevent them from desiccating.
On this particular winter evening, the heavy storm clouds parted to the west shortly before sunset. As the sun dropped below the horizon, it lit the underside of the stormy sky causing it to blaze with color for less than 5 minutes before the spectacle vanished even more quickly than it had appeared.