Saguaro National Park - Arizona

Established October 14, 1994

91,443 acres

Symbol of the American Southwest and North America's largest cactus, the saguaro's imposing stature and uplifted arms give it a regal presence. Perhaps that's why this burly giant, whose only bits of exuberance are seasonal blossoms and figlike fruits at the tip of its limbs, has been dubbed the "desert monarch."

Carnegiea gigantea is the trademark of the Sonoran Desert, whose basins and ranges rumple 120,000 square miles of northwestern Mexico, southern Arizona, and southeastern California. Saguaro National Park is composed of two sections. The westerly Tucson Mountain District embraces about 24,000 acres of the hotter, drier, less-vegetated "low" Sonoran ecosystem, which occurs below 3,000 feet. Thirty miles east, on the other side of Tucson's urban sprawl, is the 67,000-acre Rincon Mountain District, which occupies loftier ground and has a cooler, slightly wetter "high desert" environment. Most of it is inaccessible save by foot or on horseback. Here the terrain inclines from saguaro forests into nearly pristine woodlands of oak and pine. Hikers pressing on to higher elevations find Douglas-fir, ponderosa pine, and solitude.

The Sonoran Desert's extreme temperatures, perennial drought, frequent lightning, banshee winds, and voracious predators keep the saguaro forever at the limit of its endurance. Odds against survival rival a lottery: Though the cactus annually produces tens of thousands of pin-head-size seeds—some 40 million over a life that may last two centuries—few ever even sprout. Even fewer seedlings achieve the grandeur of towering 50 feet and weighing up to 16,000 pounds.