Way down at the bottom of the country, very near the Arizona border with Mexico, lies Organ Pipe Cactus National Monument. The divide in the rugged Ajo Range delineates the eastern boundary of the park shared with the Tohono O’odham Nation. The tallest mountain in the linear chain is Mount Ajo, 4,808 feet. Remote, yes, but this premiere trail hike in the Sonoran desert has so many enchanting features it is hard to make progress.
The route showcases the western wall of the volcanic Ajo Range. Volcanism is capable of creating fantastical structures such as rhyolite spires, smooth globs of tuff, a cylindrical arch to crouch in, clusters of stone cones to play amongst and fluorescent lichen coating sheets of bedrock.
Southern Arizona had drenching rains this winter, and a super bloom is happening right now. Billions of buds and blossoms are brightening the hardscape.
Bull Pasture OverlookThe hike begins from the Estes Canyon Picnic Area and Trailhead – elevation 2,380 feet – located half way around the 21-mile Ajo Mountain Drive. Framed by saguaros, the beige symmetrical crest of Mount Ajo rises above a clay-colored 800-foot vertical wall of welded rock.
On a stone block staircase, descend into Estes Canyon and cross the wash. In 0.1 mile, the trail splits at a signed junction. Go right toward Bull Pasture, leaving the slightly longer Estes Canyon Trail for the return trip.
The path traverses a broad canyon. Healthy, plump multi-generational saguaro partner with chainfruit cholla towering overhead. The ancient creosotebush – one of the oldest living organisms on the planet – mixes with palo verde distinguished by smooth, bright green trunks.
The track switchbacks pleasantly up a west-facing bajada crowded with organ pipe cactus. The monument is the only place in the U.S. to see large stands of the columnar cactus. Bats pollinate the nocturnal blooming cream-colored flowers.
Turning southeast, walk up a bedrock spine flanking the prow of a volcanic buttress. The Estes Canyon Trail joins at 1.1 mile. Visually, my favorite segment of the hike is from here to Bull Pasture. The trail inclines steeply on a stairway of placed boulders as it probes an access cleft. Notice how the cliff layers below Ajo’s west face step down through a brown breccia band to smooth, yellow hued volcanic tuff embellished with dark striations.
The pathway runs alongside golden globs of ash-fall tuff. A westward vista opens, and then the trail swings east to ascend slabs of stone.
Reach the Bull Pasture Overlook at 1.6 miles, 3,260 feet. The established trail ends on this suspended broad bench where early ranchers grazed cattle. If you’d rather not climb the mountain, this is a worthy place to turn back. Return on the Estes Canyon Loop for a total of 4.1 miles and 880 feet of gain.
Mount AjoFor those going on to the peak, the proper social trail crosses directly east beyond the sign. It is the most obvious amongst a myriad of wildcat paths. Faithfully follow cairns southeast pivoting around the end of Bull Pasture at 2 miles. Walk a few paces south to see Diaz Spire and Peak, named for Captain Melchior Diaz, Spanish conquistador and leader of the Coronado Expedition, 1539-1542.
Bearing northeast, do a short climb then essentially hold the contour beneath the cliff band. The trail crosses the stone floor of Estes Canyon wash and then uses the draw to penetrate the armored divide. Look up to locate a circular arch. To stand in the window, approach it off-trail from the east.
Pitch steeply, topping out momentarily on a slim saddle in bulbous cones composed of compressed volcanic ash. This is an outrageous and irresistible place to stop and play. There is one final steep and loose segment. Pass beneath startling fountains of frozen rhyolite.
The route bends northerly to reveal a false peak at the south end of the summit ridge. We are now walking on sunshine. Blazing yellow lichen clings to welded tuff, igneous rock containing debris fragments from an explosive volcanic eruption.
The footpath makes an ascending traverse to claim the top of the divide. All the country to the east is property of the Tohono O’odham Nation. The slope dives to the floor of the Barajita Valley and a couple of dusty tracks can be seen crossing to the Gu Vo Hills.
Stay on the sanctioned trail as it moves east to bypass the false summit and a problematic outcrop. The mountaintop comes into view at 3.8 miles. It is great fun climbing the summit block. Follow the path as it wanders skyward on breccia, a volcanic conglomerate with large chunks of random rock picked up by flowing lava. Everything gets cemented together to form new rock as it cools.
Crest the peak at 4.25 miles. The prominence is a linear series of breccia mounds waiting for exploration. The summit register is located inside an enormous metal box. There are various structures scattered all over for one purpose or another which detracts from the natural order. Soaring ravens and raptors will remind you that you are in wild country. Over 270 birds have been identified at Organ Pipe.
The vista is unparalleled from the highest eminence in the 517-square-mile park. To the west, you can pick out our route, Ajo Mountain Drive, Twin Peaks Campground, the Diablo Mountains and other prominent peaks within the monument. The town of Sonoyta, Mexico is 13 miles southwest as the crow flies.
Walk a few paces north to see the free-standing, cube-shaped monolith Montezuma’s Head, named in honor of the ancient O’odham deity, I’itoi. The Santa Catalina Mountains rise above Tucson, and Baboquivari Peak claims landmark status throughout southern Arizona.
Estes Canyon TrailRetrace your steps to the Estes Canyon Trail and turn right. It adds a half mile but enriches the experience. The beautifully crafted path switchbacks to the canyon floor. It is mostly flat from here to the trailhead. Walk through a lush arboretum of Sonoran plants.
Twenty-six cactus species live in Organ Pipe. By April, the cholla and ocotillo will be blooming. Wait until May for organ pipe, saguaro and Engelmann pricklypear. It might be July before the barrels start blossoming, but by then it is impossibly hot.
Little curled up brown balls of innocuous spikemoss border the trail. After a soaking rain, this groundcover aptly named resurrection plant turns a moist vibrant green. Likewise, throughout this magnificent hike, I felt like I’d died and gone to heaven.
http://debravanwinegarden.blogspot.com. Debra Van Winegarden is an explorer and freelance writer who lives in Durango.