A quiet riot at Organ Pipe Cactus National Monument

AJO, Ariz. — One of the things that’s so remarkable about Organ Pipe Cactus National Monument in Arizona is how different it is from California’s national parks.

I’m not talking about desert scrub and cactuses; those things can be found in several of California’s national parks.

I mean that Organ Pipe doesn’t have a General Sherman or a Half Dome or a Badwater, the superlative landmarks that define some of California’s greatest natural assets.

The majesty here is more subtle. It’s a flock of quail scattering, head plumage flailing, as a hiker comes upon them. It’s the hypnotic buzz of bees enamored with the fleeting flowers begot by the miracle of scant rainfall. It’s the unquestionable Southwest red of a cliff illuminated by the setting sun.

The monument sits on the border with Mexico, about 120 miles from both Phoenix and Tucson and close enough to be accessible but far enough to be away from it all. Ajo, 16 miles north of the national monument, is the local metropolis with a population of about 4,000.

Organ Pipe is for people who want to trade the squealing of brakes and the honking of horns for a coyote’s howl or the skittering sound of a roadrunner kicking up pebbles as it scoots.

It’s quiet enough in some places that I can hear my heartbeat.

Although the solitude is the best reason to visit, the flora — including the park’s namesake cactus — is a close second.

For a crusty spot where even the most ambitious raindrops dread to tread, the park has an incredible diversity of plant species, such as clingy cholla cactuses and the palo verdes that are entirely green, from the base of their trunks to the tips of their branches. In 1976, the United Nations recognized that diversity by naming this national monument an International Biosphere Reserve.

The organ pipe cactus got its moniker from its resemblance to the towering pipes of a church organ. An organ pipe can have a dozen or more arms radiating in a choreographed fashion from the main stem, making the cactuses conspicuous, tiny green islands in the vast desert.

Impressive as it is, an organ pipe is not hardy, and most places even in southern Arizona are too cold in winter for the meek succulent. The park is one of the few spots where it grows north of the Mexican border, and even then the plant almost exclusively takes up residence on south-facing slopes.

Most of these cactuses and other plant species can be found on Ajo Mountain Drive, one of the park’s main attractions. It’s 21 miles of dirt and gravel road, but my timid Honda Accord handled it easily. Bring lunch; the National Park Service has set up ramadas (sun shades constructed from branches of ocotillo or other plants) with picnic tables in three gorgeous spots along the drive.

Before getting weighed down with lunch, though, consider a jaunt up the Bull Pasture Trail. (The trail’s unusual name supposedly comes from cattle driven up to a plateau at the trail’s higher elevations, but the trail is a bit steep for even the strongest half-ton of hoofed hamburger to climb.)

The four-mile round-trip trail takes some effort as it rises a few hundred feet in elevation over a couple of miles, but don’t be deterred by that. Just when my thighs were beginning to question why I’d decided to make the climb, I was rewarded with expansive views of the surrounding desert and clouds tickling the tips of mountain peaks miles to the south in Mexico.

The hike is especially a treat in spring, when small patches of wildflowers dot the trail’s edge and the palo verdes nearly explode with butter-colored blossoms.

As spectacular as the day has been so far, nothing beats the dinner theater in the park. And by that, I mean the sunsets.

The best place to watch the sunset is also the best place to camp in the park — Alamo Canyon campground. There are only four camping spaces in this primo spot, hidden five miles down a dusty road at the base of the Ajo Range.

When I visit, I like to make sure I return to the campground in plenty of time to make dinner before the sun goes down, because when it does, the effect is magical. The waning sunlight lights up the crimson-hued hillside just east of the campground. As the sun drops out of sight, the surrounding area seems to transition through the entire red end of the spectrum, making the emerald saguaro and organ pipe cactuses even more prominent.

And the show’s not over when the sun goes down. In the winter and spring, the Milky Way, free from the competition of city lights, really puts on an exhibition.

There are no signs pointing the way to Alamo Canyon. Unlike most national park campgrounds, this one requires campers to sign up first at the visitors center — but exclusive lodging is usually the best, right? Rangers will tell you how to find the campground. Spots are first come, first serve, so it’s best to hit the visitors center early in the day to snag one. Also, bring water; there is none available at the campground.

travel@latimes.com