Oak Creek Country

Oak Creek Country The First 280 Million Years

When the heroine of Zane Grey's Call of the Canyon first gazed in disbelief down upon the chasm of Oak Creek, she felt "at once a chill and a shudder.

"The very forest-fringed earth seemed to have opened into a deep abyss, ribbed by red rock walls and choked by steep mats of green timber."

At the time Grey brought the fictional Carley to northern Arizona, spring had draped a verdant cloak on the "deep abyss." But Oak Creek Canyon is a slender corridor of moody, ceaseless contrast. Had it been fall instead, quite another world would have unfolded below her.

Autumn arrives earliest along the upper gorge, where its wand taps the loftier, moister forests. The bigtooth maples, erupting into fiery reds, are first to don their fall dress. Then the new season subtly tiptoes downstream as though a giant palette has been spilled slowly.

Days laze into cooling weeks before scarlet sumac patches the stone walls only a few miles below, and magentas and cerises fleck the underbrush. Lower still, russet bathes some of the oaks. The willows turn orange and, finally, the cottonwoods play a golden counterpoint to the crimson cliffs that shoulder them. The whole color spectrum of seasonal passage has shown itself in only a dozen wildly declining miles.

The cottonwoods continue to march along the stream as the canyon widens, around Sedona, into the high desert of the Verde Valley. By then, still other splendors have been revealed. In every direction rise the terra-cotta-colored, light-capped spires and buttes immortalized as a backdrop for generations of Western movies. Their names evoke the gothic shapes into which eons of wind and water have worn them: Courthouse Butte, Bell Rock, the Cathedral, Coffee Pot, and Mitten Ridge.

Nature began landscaping this crazy quilt almost 280 million years ago before the first animals ventured out of the oceans. Where now there are lush woodlands and stunning red rocks, there then was a delta or floodplain that trapped sediments washed down from the ancestral Rockies.

These thickened into a deposit 1500feet deep that geologists would name after the Supai Canyon home of the Havasupai Indians. From bottom to top, the Supai Formation shades from pink to reddish brown to grayish orange or pale reddish brown all colored by a concentration of oxidized iron-hematite that forms the finer sand grains and coats the coarser sediments.

Sandwiched in, not far from the top of the Supai, is a limestone layer up to 30-feet thick that marks a momentary return of the still nearby sea.

By about 250 million years ago, widespread deserts ruled the region, stacking windblown sand into dunes. In turn, over time, the deserts retreated. Later the sea swept in and receded. Each climate left in stone its own distinct bequest each cemented one above the other, from oldest to latest. The dunes are preserved, banded above the Supai, as the buff sandstone called the Coconino. These fossil sands are rich with the tracks of spiders and small reptiles, not unlike those to be found in present-day deserts.

For many years, paleontologists were baffled by why all those ancient footprints appeared to head only uphill until someone noticed what happens with modern lizards. When they scamper up, their tracks remain. But going downhill, shifting sand fills in behind them.

The streams that followed, surfaced the Coconino with white Toroweap Sandstone. Finally, some 225 million years ago, the ebbing sea laid down the uppermost Kaibab Limestone, buff in hue and filled with fossilized sponges and seashells.

In humid climates, rainfall tends to dissolve organic accumulations of that sort. In such arid regions as Arizona, the limestone hardens, which is why the Kaibab makes up the rimrock here.

Approximately 13 million years ago, great faults began to slice slowly through these cake-like layers. One such break blueprinted the course of Oak Creek Canyon. When the fault yawned, its western wall was thrust up 500-feet higher than the eastern side.

The Canyon already had divided when violent volcanic upheavals spattered the country with lava flows and poured great dark columns within the Canyon itself.

But through all these ages, the sandstones of the lower Canyon somehow escaped the warping and writhing that contorted much of the Earth. They held fast, instead, in the bright horizontal beds that erosion has molded.

While Nature's sculpture provides the postcard picturesqueness, biologists are more entranced by the astonishing array of living things. The diversity is especially impressive for an area so small; the Canyon rarely is more than a mile across. Much of this variety results from dramatic differences in elevation.

A highway threads through the Canyon for 16 miles, descending from the Mogollon Rim, where the elevation above sea level is 6407 feet. The road reaches the floor at Sterling Spring, the source of the year-round creek. There, the elevation is 4907 feet. At Sedona, it is only 4320 feet. So, the creek tumbles between them from a subalpine setting down to the cactus country of the arid scrubland.

Because temperatures and precipitation shift quickly here over short distances, it generally is considerably cooler and moister up-canyon than down.

Scientists generalize that every 1000foot drop (or rise) in elevation is the ecological equivalent of traveling 300 level miles north or south. From the ponderosa pines of the rim to the valley, then, a motorist in effect traverses more than 600 biological miles.

Near Sterling Spring, the forest giants are high-country, cone-bearing ponderosas and Douglas firs, along with the maples and occasional aspens and spruce. This is Zane Grey land, where he lived while absorbing inspiration for Call of the Canyon, written in 1921. Chaparral low thickets of such shrubs as manzanita and silk-tassel bush, start sprinkling the cliffs a few miles lower. Chaparral typifies dry, warm foothills.

Around Slide Rock, about halfway down the Canyon, pines and firs give way to woodlands of oaks that, unlike most eastern oaks, are evergreens. And not far from where the Canyon ends, pygmy forests of pinyon and juniper dominate the hillsides.

The streamside plants are similarly transformed from elderberries and alders up above to, in the lower reaches, cottonwoods and walnuts.

Each of these vegetative communities harbors a unique assembly of smaller plants and animals that have evolved for survival in these very particular places.

Dippers, or water ouzels, may be seen almost anywhere on the stream as they ply their submarine skills. Dippers are slate-gray, stubby-tailed little birds. To satisfy a considerable appetite for aquatic insects, they dive into the stream and then walk along the bot-tom in pursuit of their prey.

Most of the residents remain close to their rather restricted niches, however. Abert's squirrels, with their pointed, fluffy ears and big, bushy tails, seldom stray far from the pines and firs. This is the case, too, with a climber of note, the Arizona tree frog.

On the other hand, the Arizona tree frog's cousin, the canyon tree frog, lives closer to the creek, where it is a neighbor of the rare narrow-headed gopher snake. The Arizona tree frog, in its late-summer breeding season, can be witnessed high among the branches as it dines on bugs or simply loafs reflecting on whatever it is that makes frogs reflective.

Still, the boundaries, not rigid to start with, that set apart the plants and animals are apt to be more blurred here than elsewhere. This is because of such elements as the very presence of the stream so near the desert's edge, different exposures to sunlight and the erratic microclimates created by the canyon labyrinth.

As biologist Stewart Aitchison told me: “It isn't uncommon along Oak Creek to find chaparral on a sunny, south-facing slope and around the corner, at the same elevation, ponderosa pine and Douglas fir.” Since the flora sometimes intermingles, so does the fauna. For instance, the hepatic tanagers are birds at home in the conifers, while their slightly smaller kin, the summer tanagers, live mainly in willows and cottonwoods.

Aitchison, however, remembers a recent spring when warming weather was interspersed with days of reluctantly departing chill. That spring, both tan-agers nested at Cave Spring, a piney campground a couple of miles below the base of the rim.

Like Zane Grey, who mercifully abandoned his first name, Pearl, when he became a writer, I too lived for a time near the creek. That was many years ago, but the images are easily remembered.

It would be difficult to forget the ephemeral Niagaras that cascade down the high canyon faces after summer storms, the rainbows that seem simply to flower from the multicolored terrain, the sublimity of the sunrises which glint First off the white Toroweap and then gradually embrace in their blush the reds of the sandstones below.

My daughter, Maggie, who is 14, is less impressed by the esthetics than by Slide Rock. Slide Rock is a series of shallow troughs, carved over the centuries in the stream's sandstone bedrock and abraded further, each summer weekend, by a thousand or so bathing-suit seats. The idea is to sit down, let go, and careen down the creek.

What makes Slide Rock slippery? Dr. Dean Blinn attributes this to a patina of golden-brown diatoms and blue-green algae. Blinn, a freshwater biologist, and his students from Northern Arizona University have catalogued some 500 kinds of algae in the Canyon.

That means there are twice as many algae as there are species of vertebrate animals there.

Although casual visitors may notice no more than the long green filaments that stick to stones and dangle in the creek's currents, the algae have a higher purpose than merely coating Slide Rock. They oxygenate the water and produce the particles that feed some insects eaten by the birds and fish.

Before Blinn or Maggie or me or even Zane Grey there were the Indians. The Hopis say they came this way, in dim lit antiquity, on their way to their present villages to the northeast. Because there were Indians, the archaeologists followed, of course. One was the noted Jesse Fewkes. He came in 1895 and predicted that the area would become a favorite of tourists. In no way could he have imagined how correct he was. Now, some 2 million motorists a year drive down Oak Creek.

Drive through is all that most of them do. In one way, this is fortunate because on busy summer weekends parking places can become precious. Nonethe-less, a hurried visitor is likely to miss the rarer sights, such as the animals.

Although they seldom are seen within the crowded confines of the main canyon, short hikes through some side canyons often reveal the tracks of both bears and mountain lions.

Campers are likelier to encounter raccoons, ringtail cats with foxlike faces, coyotes, and skunks.

Deer may stray across the highway. But both deer and elk prefer the more remote reaches of Munds Canyon, which empties into Oak Creek at Indian Gardens, between Slide Rock and Sedona. In severe winters, the deer and elk slip down from the higher elevations and are thick on Munds Mountain, to the east of Sedona.

Nor will the casual visitors have the advantage I had recently on several revisits to the Canyon. I returned in the company of scientists who know it well. Greg Goodwin, a Forest Service wildlife-habitat specialist, came along to acquaint me with the nuances of the vegetation.

In an endless round of visual excitement, sun and rain and cloud create dazzling, often mind-boggling, images in Oak Creek Canyon. (Far left) William Jensen, (Left and below) Dick Canby

Winter in magnificent Oak Creek Country, where gothic shapes created by eons of wind and water have such names as Courthouse Butte, Bell Rock, the Cathedral, Coffee Pot, and Mitten Ridge. (Far left) Dick Dietrich, (left) Tom Canby, (Below) Bob Clemenz (Following panel, pages 24-25) Summer clouds backlight the dramatic spires, buttes, and promontories of Oak Creek Country. Bob Clemenz

(Left) Dramatic elemental forces of creation are still at work in Oak Creek Country. Dick Canby (Far left) The aftermath of a summer rainshower fills the hollows of ancient rock in Oak Creek Canyon. David Muench (Below) A soft morning mist creates a timeless moment of ethereal beauty at Red Rock Crossing near Sedona. Bob Clemenz

Text continued from page 19 Goodwin knows a rare buttercup, the bugbane, whose white flowers may be seen in shady places and where to find greenish-purple orchids and a scarce daisy that grows in the cracks of canyon walls.

Close to the canyon mouth, he pointed out the Arizona cypresses, shaggybarked trees that look a little like overgrown junipers and persist in some side canyons. These are vestigial stands of a plant that, when the climate favored them more, was widespread over Arizona.

With Blinn and Dr. Milton Sanderson, an aquatic entomologist, I was given a glimpse into some often overlooked worlds.

We paused first, some 13 miles south of Flagstaff, where the highway departs the dense ponderosa forest and comes suddenly upon the deep cleft far below. I remembered Carley's “chill and shudder.” On our left, to the east, Pumphouse Wash had etched its way deep in the sandstone, one of the usually dry branches that sometimes swell the creek with snowmelt and the runoff from summer storms in the high country.

To the south, 7076-foot Wilson Mountain lorded over the lower canyon. The name memorializes a settler from Arkansas with a fatal disposition fordispatching bears. In 1885, Richard Wilson carried a small rifle in search of a large bear. His remains were discovered 9 days later.

The dropoff at the vista point is 1500 almost sheer feet. But the pavement sidewinds down 2 ledgy miles to reach Sterling Spring. We stopped not far below the spring, where seeping sandstone gives birth to the stream. Hurrying southward, the creek is nourished by an uncounted number of pure springs. A normal summer flow of about 6000 gallons a minute gushes over Slide Rock. At Grasshopper Point, less than 5 miles below, the flow is three times that.

But where we stood, hard by the headwaters, the creek was little more than a faintly murmuring mountain brook that moves less than 500 gallons of water a minute.

Foliage formed a dense umbrella over the creek. Leaves that fall from the canopy into the stream and are broken down by bacteria - provide the necessary nutrients to sustain the aquatic life. Farther down, as the canyon opens and the trees decrease, algae will replace the leaves as the creek's energizer.

Blinn leaned over to pick a rock from the creek, turning it over to disclose colonies of caddis fly larvae and mayfly nymphs. These insects find daytime refuge from predators on the rock bottoms and come out at night to feed.

Like the algae, the insects here are remarkable both in numbers and in kinds. Blinn and Sanderson estimate there are 275 species far more than in any but a few other waterways in the nation.

Dragonflies and damselflies are the most conspicuous as they buzz low along the water, making in-flight meals of midges. But these are far outnumbered by the tinier insects, such as the moth-like caddis fly, which has hairy wings. Most insects have scaly wings. One caddis fly is found on West Fork, Oak Creek's only full-time tributary, and nowhere else.

Oak Creek, after it leaves Sedona, surges another 45 meandering miles through desert shrubs and grassland until it knifes through limestone hills to join the Verde River.

We went to watch them merge, from the brink of a low mesa where our shoes scratched a foam-like carbonate coat left behind when this was an ancient lake. For a while, we simply looked on as the blue water of the creek was wedded with the green of the Verde which then surged on south.

It is difficult not to become philosophical at such moments. What will happen as man, so much a newcomer to this very old land, arrives in ever greater numbers? Blinn and Sanderson agreed with most of the other scientists I have asked. Because it is blessed with moisture and regularly scoured with clean water, Oak Creek is a more forgiving environment than are the fragile deserts below.Dean Blinn thought a minute. As we turned to leave, he said: “It's still remarkably pristine considering the heavy use. With good conservation practices, it's a system that can survive.” Far to the north, the rocks glowed a deep ruby in the sunset. Blues mantled the rim above them. And as we considered the future, the fading day allowed us a last look across 280 million years of the past.