“The saguaro is a curious thing.
Tall and long and very spiky.
I would like to give it a hug
But I’m afraid that it might bite me!”

The Sonoran Desert is a complex, unique ecosystem. Spreading across southern Arizona for miles, vast yet not empty. The crowning jewel of the Sonoran Desert is the massive, long-lived saguaro cactus. Tall and many-armed, it is an iconic symbol of the American Southwest. In Saguaro National Park, large stands of saguaro are protected in two similar yet different districts. There, you may catch a glimpse of the secrets of this monarch of the desert.

The Hohokam peoples lived in this area some 2,000 years ago. Living alongside the Gila and Salt rivers in what is now the Phoenix basin, they were one of the earliest cultures to use irrigation for crops. They are considered to be the original builders of the extensive canal system in the Phoenix metropolitan area. The Hohokam were also notable for their pottery and shell art, which has been found across the region. Their imprint in the National park was minimal, although they did leave petroglyphs in the area.

The Hohokam disappeared around 1450 CE. But the their descendants, the Tohono O’odham and Pima(or Akimel O’otham) peoples, still live in this region.

Until 1846, they mostly lived in peace, with little contact with others. After the Mexican-American War in 1846, however, the Americans sent expeditions to the area. The Akimel O’otham ceded most of their land to the U.S at the end of the war, except south of the Gila River near what is now Tucson. From 1853 to 1860, the Akimel O’otham lived cooperatively with the settlers and were prosperous. At the end of the Civil War, competition between settlers and natives for resources led to the government forcing the natives onto reservations. The white man populated the area, but the tall saguaros remained mostly undisturbed.

In 1920, members of the Natural History Society of the University of Arizona expressed interest in protecting the saguaros, but it went mostly unnoticed until 1928, when University president Homer L. Shantz took action. His vision of a Cactus Forest, available for study for future generations, eventually won over the haters and Saguaro National Monument was created on March 1, 1933.

At first, only the Rincon Mountains were in the park. In 1961, the Tucson Mountain District was added, protecting the cactus lands on the other side of Tucson. The TMD is lower, wetter, and less vegetated than the East side of the park.

And on October 14, 1994, Saguaro was made a National Park.

Saguaros grow slowly. These little ones are probably 15-20 years old.

Although this is Saguaro National Park, the saguaro is not the only plant here. In fact, the Sonoran Desert is full of wondrous flora.

Start with the saguaro. Most of the saguaros here are tall and old, for it grows slow, reaching 3 feet in 25 years. Once it hits 100 years, it will grow its first arms. Saguaros can live up to 200 years and reach up to 60 feet high.

“Saguaro cactus
Sentinel of the desert
Tall as trees, odd plant ”

— saguaro haiku

The nature of a saguaro, along with most other desert plants, is to conserve water. And the saguaro can hold a lot of water. The biggest saguaros can weigh 16,000 pounds!

Hiking in Saguaro National Park is a blast! Just watch your step!

Saguaros produce tens of thousands of seeds every year, but few ever sprout. Those that do become home, in time, to birds of all types.

Other cacti populate the area as well. Barrel cacti are common, shaped like small barrels and covered with long spikes that look like fishhooks. Cholla (pronounced choy-ah) cacti are shaped like trees, with branches covered in numerous tiny spikes. A variety known as teddy bear cholla has spines so small it looks like it is covered in fur. Prickly Pear cacti are very common across the West, and are found here in large numbers.

Trees are rare in the desert, but shrubs are less so. The ocotillo (Spanish for little torch) consists of several skinny bare stalks growing straight up. When it rains the ocotillo is covered in small green leaves that quickly fall off. Jojoba, another shrub, is known for its oil, which comes from its acorn-like seed.

Palo verde trees are rarely 15 feet tall, yet are essential to the saguaro catcus’ survival. Young saguaros will grow under the protection of their taller “nurse tree” for the first 50 years of their life.

The lower areas of the park are thick with cacti.

Many animals make Saguaro National Park their home. Everything from tiny lizards under rocks to birds from the far north to great mountain lions covering many miles.

Many species of reptile live among the cacti. Gila monsters, the only venomous lizards in the U.S, are slow and colorful, with an entrancing black and orange pattern. Snakes abound, but few are seen. Several species of rattlesnakes live in the park, including the biggest of them all, the Western Diamondback. Other snakes include the colorful Coachwhip and the cannibalistic Kingsnake. Type of lizards include Whiptails, Spiny Lizards, and Regal Horned( More commonly called Horny Toad).

“Gila monster? Well
Only in name. Slow, but quite
Poisonous, brother!”

— gila monster haiku

Mule deer and Javelinas are the large mammals here. Javelinas, mistaken for wild pigs, are technically called Collared Peccaries. They love to eat prickly pear cactus, among other things.

“Not a pig, nor boar
Hairy and cactus-eater
Javelina, sir!”

— Javelina Haiku

Carnivores in the park range from the elusive mountain lion to the commonly seen coyote and bobcat. An interesting development is that in recent years, Jaguars have been spotted in the surrounding mountains. The third-largest cat in the world once was common in this area, and the reappearance of these large predators to the region signals good things for the ecosystem.

Cholla (Hoy-A) cacti look almost fuzzy from a distance, having more spikes on its many arms.

Southern Arizona, besides having a large population of native birds, is smack in the middle of a major migration route. A huge number of birds descend on this area in the winter, and this combination makes for one of the most diverse areas for birds in the U.S. Cactus Wrens, Mourning Doves, Curve-Billed Thrashers, Phainopeplas, and Pyrrhuloxias are just some of the songbirds that live here. Gambel’s Quails live mostly on the ground. Roadrunners eat scorpions and snakes, and run up to 35 mph. Red-tailed hawks and turkey vultures soar on the thermals.

The Sonoran Desert is home to both scorpions and tarantulas. Tarantulas are nocturnal and are mostly seen in the fall, when they emerge from their holes and mate. Many species of Scorpions inhabit this area. Scorpions are ancient creatures, having changed little in 400 million years.

The land of saguaros is fascinating in many ways. A special place it is, home to many organisms, and also a seemingly strange contradiction; a forest in the desert. Thanks to the foresight of the NPS to preserve this unique land so you too may enjoy the majesty of these desert giants.