Death-defying calm

COSUMNES RIVER PRESERVE — 

Nightfall on a cloudless evening does not hurry. Wings flash across the sky, and frogs, emboldened by the fading light, take up singing as birds fall silent. Just above the horizon, a sliver of the moon emerges in the airbrushed light. Only Venus is more bright.

Back in the city, the first episode of “CSI” is about to air. Here, earth and grass are still warm, pungent from a long afternoon beneath an oak tree at the Cosumnes River Preserve in the California Delta, at the confluence of the Mokelumne and Cosumnes rivers, 60 miles northeast of San Francisco. The Central Valley’s last wild river, the Cosumnes originates in Eldorado National Forest in the High Sierra at 7,600 feet. It draws from a basin of 1,200 square miles and funnels down granite slopes into wooded foothills before sliding into this flatland.

Here, cottonwoods, willows, ash and oaks line its banks in a thick, hummocky profusion. California wild grape, poison oak and California blackberry intertwine in the lush understory. Beyond the river, cultivated fields, protected by levees, give way to rolling hills of dried ryegrass that spread like ocean swells around this solitary oak. A mile to the west, Interstate 5 roars with a low white noise, and a distant freight train begins its labored crescendo.

Nature’s beauties are often small and patient and unnoticed. Even the most dramatic, like birth and death, are unremarkable because they take place without expectation. Wildlife is, as poet Gary Snyder reminds us, “often simply a call, a cough in the dark, a shadow in the shrubs.”

A shooting star burns through the eastern sky, busy with planes and bright with the glow from Galt, an ag town of nearly 20,000.

Once an acorn — a thimble-sized nut revered by Native Californians — buried and forgotten by a squirrel or a jay, this tree grew in a world and a place we have no record of, certainly before the Gold Rush, perhaps before the arrival of the Spanish. But an understanding of this oak begins with an appreciation of a scale of time that is unimaginable. Paleobotanists tell us that the first plants began to form nearly 375 million years ago and that in these leaves are the traces of a world still largely submerged — of giant horsetails, club mosses and ferns just starting their prehistoric climb toward the sun. Fossils of the first oak trees have been dated to nearly 45 million years ago, 40 million years before the arrival of apelike humans in Africa.

The ground slopes slightly away from the trunk, evidence of its slow growth. The rustle of the leaves rises and falls in distinct cadences as if the oak were being played by the wind, nuance modulated by the velocity of each gust. In the distance, the limbs of two trees rub one another. A great horned owl calls from across the field, then suddenly alights overhead — who-who-who-who who-who. Somewhere in these fields tonight a mouse or a vole will die in its talons.

There are 20 species of oaks in California, nine trees, 11 shrubs. Five trees, including this valley oak, are deciduous. These oaks once flourished along rivers in the Central Valley, where their roots found water no more than 30 or 40 feet beneath the surface. Yet today, it and other species are threatened. Vintners ax them for more acreage, ranchers blast them for more grazing land, developers bulldoze them for more homes.

This tree has been spared. It stands nearly 80 feet tall, its trunk 12 feet around, its branches arcing out in a tangle of wood and in clusters of leaves that nearly touch the ground. A blaze, its meaning long forgotten, scars the furrowed trunk. The ranchers who owned this property before selling it to the Nature Conservancy held barbecues here, and a former secretary of the Interior once stood at this spot.

The stars of the Big Dipper shine though the swaying canopy. Then, in an instant, they fade.

A natural mosaic

“Only that day dawns to which we are awake,” writes Thoreau, and the awakening begins with the birds, whose polyphonies quickly stake out territories lost during the night.

As light creeps into the sky, colors creep into the clouds, which break up and fracture into blues and reds and yellows. A scrub-jay squawks out of sight. Flashes of white — swallows, from the look of their tails — jet out toward the river and bank over the field.

When the sun tops a forest of oak and ash to the east, its rays turn this tree into a mosaic of light and shadow. Its branches look like tributaries, its leaves like a jigsaw puzzle. Overhead in the canopy, a bird with a soft green breast and dark wings hangs upside down, working its way through the pieces.

A house wren has made its nest in a hollowed-out limb. The chicks are hidden, but their hoarse, crackling clamor is clear. The wren jumps from branch to branch — a cricket in its mouth — before diving into the hole and hopping out as fast.

The ecosystem of an oak is one of the most varied and complex in the West. More than 300 species of birds, mammals, reptiles and amphibians depend on these surrounding woodlands for their survival. Their names are buried in the pages of a field guide. An insect, perhaps a mayfly, a damselfly or a winged ant, lands on a nearby leaf. So much of the natural world is a mystery.

When God gave man providence over Eden, we are told, man was charged with the responsibility of naming everything he saw. The task was not a capricious one. Man in his grace knew a sparrow to be a sparrow, a fox a fox, an oak an oak. After the Fall, he lost that knowledge. After the Fall, he was separated from the world that surrounded him and ever since has tried to bridge that gap.

“The physical landscape,” Barry Lopez writes, “is baffling in its ability to transcend whatever we would make of it…. The mind, full of curiosity and analysis, disassembles a landscape and then reassembles the pieces … trying to find its place within the land, to discover a way to dispel its own sense of estrangement.”

When climbers ascend a face, when surfers ride a wave or rafters follow a river, the intent is the same. Beyond the thrill, the danger, the promise of success is an urge to connect with a wildness greater than and divorced from who we are.

By 10 a.m., outside the ring of this tree, red-winged blackbirds and meadowlarks flit among the cattails and reeds growing by the slough. The wind, drawn in from the Pacific by the rising valley heat, has kept the mosquitoes away. Ticks line the long stems of grass along well-trod paths, waiting to attach themselves to warmblooded passersby.

By 11, only the house wren is active. This slow exposure to the day — to the changing light, the pace of the sun, the changing shadows — reveals black owl pellets, cast-up remnants of fur and bone that look like coyote scat, fallen in the grass that grows along the perimeter of the tree. Mistletoe hangs raggedly from the lower limbs. Wasp galls protrude from branches like forgotten Christmas ornaments.

From afar, this oak is nothing but shadow. Up close, its leaves are among the most distinctive in nature. Their lobed design has given the tree its name, Quercus lobata. One naturalist suggests that this particular shape is best suited for hot summer temperatures, that it allows not only for maximum evaporation of water — thus cooling the tree — but also that it lets more light pass through the canopy for the leaves beneath.

More than 10 years ago, Bill McKibben argued that the knowledge gained in the Information Age was mostly specious. In “The Age of Missing Information,” he contrasted television with nature, mediated experience with authentic experience. “You have to listen harder to the natural world so you can separate out the primal song from the songs of our civilization and from our static,” he wrote.

What is the primal song, and what is our static? A buyers’ guide for an outdoors magazine recently recommended a list of seasonal supplies: sunglasses ($99), a fitness watch ($369), a digital camera ($999), binoculars ($899), a backpack ($200), shoes ($225), a tent ($285), a sleeping bag ($300), a camp stove ($80), a jacket ($119), running shoes ($110), a bike ($2,380), a kayak ($999), a sports rack ($349) and luggage ($175).

Inherent in each item is a tacit commandment to act, to move, to do. We are not often invited to be still. We speak with reverence of Thoreau’s famous summer morning — “I sat in my sunny doorway from sunrise till noon, rapt in reverie …. “ Then we pick up the trail again to some new urgency, a pressing destination. To what extent have we subjugated need to desire?

By 1 p.m., hot sunlight lances through the branches of the tree, whose shadow is slightly dappled and unmoved by the breeze. This tree is healthy. But oaks can die suddenly: one summer providing shade and the next lying split in half, dead at the core. Such a fate may await this tree, and then the field would be empty but for the snag, a decaying relic releasing its long history into the soil.

Why do we seek the outdoors? E.O. Wilson explains it with the word “biophilia”: a love of nature, a genetic predisposition for wildness that goes beyond its beauty or its implicit challenge. Wilson believes that the preservation of the world lies in understanding and appreciating the wonder and awe that nature arouses.

Perhaps our avidity for nature today is a measure of our distance from it. Is it any wonder that the Romantic Movement — the tradition of such nature writers as Wordsworth and Coleridge — arose at the start of the Industrial Revolution when the splendors of their world were fast being eclipsed by the press of cities and modernity?

We grasp more anxiously for what seems out of reach, as if we need to compensate for what’s missing. It’s ironic then that we further that distance by searching for the best or doing the most and deprive ourselves of lessons that have long sustained us.

As the heat of the day peaks and wanes, the sun sneaks its rays beneath the canopy and brightens the limbs and branches of the tree. In the twilight, the lichen on the bark is surprisingly green. Twenty-four hours are nearly over. Soon the sun will set, and the world will glow, lavender spilling across the sky. And the tree itself slows, its own photosynthetic metabolism ebbing in the fading light, where somewhere an owl prepares to hunt.