Wild Thoughts from Wild Places, page 10
The Verdugo Mountains encompass Wildwood Canyon Park. Almost thirty years have passed since Don Gill collected his data, with hillside dream houses and cantilevered patios usurping canyon habitat all over L.A., but Wildwood remains (in its modest and insular way) wild. Today I’ve got the park to myself. I sit in the rain, waiting and hoping for some evidence that C. latrans is still around. I wonder: How much longer will Los Angeles tolerate the presence of coyotes, and vice versa?
• • •
ON ANOTHER winter day, I sit on another steep hillside, watching a pack of four decidedly nonurban coyotes. They are prowling across a snow-crusted sweep of bottomland along the upper Lamar River in Yellowstone Park. These are handsome, grayish cream animals in good condition, contentedly absorbed in hunting for voles, small rodents that move through snow tunnels under the crust. The coyotes are oblivious to me, and to Dr. Robert Crabtree, the coyote researcher who has brought me here. This group of animals, according to Crabtree’s nomenclature, is the Fossil Forest Pack. The female wears a radio collar. One of the younger males seems to be limping. To Crabtree, they’re familiar individuals with a known family history.
Bob Crabtree has spent eight years studying the demographics and social structure of coyotes. He did much of that work on an ecological reserve in the sagebrush of southcentral Washington state; more recently, his site is Yellowstone. The coyote populations that he has sedulously watched and measured differ in one crucial way from most other coyote populations in the United States: Crabtree’s have been “unexploited” populations, protected from hunting and trapping.
The institutionalized persecution of coyotes in this country over the past sixty years is a huge and outrageous story that deserves its own telling, but I won’t launch into that here. I’ll just mention that your federal tax dollars support a program called Animal Damage Control, administered within the Department of Agriculture, the main service of which is to kill about 76,000 coyotes per year. The beneficiaries of that service are ranchers, chiefly sheep ranchers, who graze their animals on both public and private lands. In addition to the ADC harvest, another 350,000 or so coyotes are killed privately by hunters and trappers in a typical year. The net result of all this coyote slaughter—Bob Crabtree suspects, and expresses in judicious scientific terms as we sit talking—is exactly the opposite of what’s intended.
Destroy coyotes indiscriminately, he explains, and you destroy nonreproductive adults. You kill mature alpha males and alpha females (that is, pack leaders) in the six-to-twelve-year-old class, aging animals that are robust enough to maintain their dominant status and their territories but too old to be fertile. (In other words, these relatively few individuals hold the exclusive social prerogative to breed, but in many cases no longer exercise it.) Kill them and you encourage younger, submissive animals to claim dominance and begin breeding. You increase the reproductive rate of the population. Do that and you increase the predation against sheep. Why? Because young coyotes with newborn pups account for most of the lamb killing (or the killing of elk calves in Yellowstone), according to Crabtree. The growing pups need such windfalls of protein. Older coyotes without pups tend to take the easier, safer course, feeding on rodents, rabbits, and other reliable small-item foods.
Among the unexploited populations he has studied, Crabtree has seen the result of allowing those mature alphas to survive. “It’s a very important form of population limitation,” he says. “Because these old alpha females are keeping whole territories unproductive. And the consequence of that is lower predation on lambs.”
The Fossil Forest Pack work their way downstream on the far bank of the Lamar, passing below our overlook. Through my binoculars, I watch the female pounce. She digs, she roots, she brings up a vole and swallows it. Several minutes later, she and her mate and the two younger males tilt back their heads and break into a chorus of yipping howls: voicing a territorial claim, no doubt, but also perhaps venting pure pride and satisfaction in their coyotehood, on a fine piece of landscape where they have never set eyes on a sheep.
Crabtree makes one further intriguing point. Sixty years’ worth of largely indiscriminate killing by ADC trappers and others has inevitably reshaped the American coyote, producing an animal that’s more clever and wary and resourceful, more problematic, than ever before. The fittest have survived, and doggone if the fittest aren’t harder to trap, harder to poison, harder to fence out, harder to fool, harder to kill despite all the helicopters and leg-hold traps and high-powered rifles and cyanide booby traps that ADC can muster. “They’ve created their own worst nightmare,” says Crabtree, not without sympathy for the many trappers and ranchers he has gotten to know. “They’ve created a coyote that’s impervious to their means.”
• • •
I SIT IN the rain, wondering: What sort of coyote has Los Angeles created?
It’s a creature that will jump over chainlink for a bowl of Alpo. It’s an animal that can learn and remember which storm-sewer channels lead to which golf courses, which duck ponds and swimming pools offer potable water when the hills are dry, which dumpsters behind which supermarkets are likely to be overflowing with old vegetables and delightfully rancid fish. It’s a beast constantly on the alert for unattended barbecued chicken. It’s a predator that, like some two-legged ones, is at home on Mulholland Drive. It has eaten from the Tree of Forbidden Knowledge, and it recalls fondly the taste of Fifi and Mr. Boots.
I confess that I find this neither sad nor inappropriate. Better for the people of Los Angeles to share their city with one slightly corrupted species of Carnivora, I think, than with none at all, and the coyote is ideal for the role. It’s arguably more similar to Homo sapiens, in ecological terms if not anatomical ones, than any other species of animal, including the chimpanzee. And persecution by humans just makes it more similar still.
Will coyotes still haunt this city in a decade or two? I asked that question of a veteran trapper for the Los Angeles DAR. “Oh, definitely,” he told me. “Twenty years from now? I’ll guarantee it. A hundred years from now. They’ll be around. They’re survivors.”
But after an hour’s soggy vigil, I’ve spotted no coyotes on the game trails of Wildwood Canyon Park. Not this particular morning. And my hands have gone numb. Time to move. I descend to the stream bottom and start hiking downstream, shin-deep in the water, tunneling my way out beneath a fallen archway of riparian brush. I’ve got no other choice but to walk the stream, since the game trails are rambling and evanescent, and the chaparral-thick hillsides are impassible. On a low grassy bank, sheltered by an oak tree, I stop. I notice something there, partly buried in silt. It’s a coyote skull.
Experts will later confirm that identification, though I’m fairly confident from the first glance. It’s muddy but meatless, a graceful long-snouted Yorick nicely bleached by time and weather. I examine its eye sockets, its remaining few teeth. What’s your story, skull? Maybe the animal it belonged to lived a long tranquil lifetime right here within the fastness of the Verdugo Mountains, never venturing down into Burbank, never robbing a barbecue, never killing a pet, never digging for moles on a fairway, never committing a single act of subversion or trespass against the human-made world. But naw, probably not. Probably this was another urban guerrilla. Still, the fact that its mortal remains came to repose here, on a stream bank in a pathless canyon, suggests that the critter was lucky or cunning enough to die a natural death.
Good. Feeling outlawish, willfully pilfering a natural artifact from Wildwood Canyon Park, I wrap the skull gingerly and put it into my bag. Then I slog on. They’ll never catch me. I’m only a half hour from my taxi.
Reaction Wood
I’ll start with the memory part, leaving the science part for later. When I was a boy I had, in lieu of a dog, in lieu of a grandfather, a tree.
It was a towering old black walnut that stood near the south edge of our yard in suburban Cincinnati, with a pair of stout lower limbs sticking out horizontally like the arms on a giant scarecrow. If my memory can be trusted, those limbs emerged from the trunk about eight feet up. Possibly they were lower and only the parallax of time and nostalgia has raised them. Anyway, one held a swing. Supporting my weight, or mine and my big sister’s together, would have been trifling to a limb of such girth—it was thick as a telephone pole. In the fog of my earliest recollections, dating back forty-some years, I can see myself gazing up at those two horizontal limbs, where they hung far beyond my little-boy reach, far beyond even my best jump. I can recall vowing that someday I’d manage to lay hold of one, somehow, and then I’d climb this wonderful tree.
Reaching the horizontal limbs, the first rung, would be the least of the problems. Just above, the tree divided into three major stalks, each nearly vertical, the easternmost of which rose to a precarious crow’s nest of small branches about sixty feet in the air. Getting to the crow’s nest would present dangers and difficulties whose solution, when I was six or seven, I couldn’t even imagine. But several years later, with a little more size and agility, I solved them. And then, over and over again throughout boyhood, I did climb the tree. I went everywhere in it that my weight would allow. I learned all its knobs and its crotches. I discovered that although the crow’s nest seemed unattainably high on its limbless stalk, I could reach it indirectly: ascending the westernmost stalk instead, then stepping over to a high notch in the middle stalk, and from there to the eastern one. I wore a path, along that route, into the tree’s black corduroy bark. Once, on a stupid show-offish whim of the sort that occasionally gets a boy killed, I climbed to the crow’s nest and down again blindfolded. I had memorized every requisite move. But the tree represented more to me than a gymnastic challenge. It was a place I enjoyed visiting; it was a living creature I respected. It had become almost personified to me, a valued companion and mentor.
Probably it was then about a hundred years old. That would have made it a sapling in 1864, when Ulysses S. Grant and William T. Sherman met in a Cincinnati hotel room to sketch out the last campaign of the Civil War. By the time my family took custody of the tree, it was no longer subsumed within a continuous hardwood forest rolling over the hills at the near northern fringe of the city. It had been spared when the forest was otherwise cleared, left to loom lonesomely over a farm landscape and then, later, over a half-acre lot. When my parents built a house on that lot in 1950, all that remained of its ecological and agricultural vestiges were the walnut tree, a hidden well shaft lurking treacherously beneath a layer of rotten timbers and soil in the backyard, and an 1825 penny, which my father found in the dirt. But the hardwood forest—or a large remnant of it, at least—survived nearby.
Beginning just beyond a thistle field that began just beyond our back fence, the forest stretched for miles, a boy’s wonderland of trees, vines, hillsides, trails, and rocky creeks full of crawdads and frogs. The northern borderlands of the city also included a local park known as Winton Woods and another called Mount Airy Forest, two parcels of protected landscape where my father and I occasionally hiked, skied, or fished. But those two were relatively distant, reserved for special excursions by car. The woods just behind our house was different in several ways: more accessible to me, more wild, a better-kept secret, unofficial, unprotected. I never did know who owned this suburban wilderness but, as events would prove, whoever the owners were, to them it was just real estate temporarily encumbered with trees.
Also unlike the two parks, it was nameless. I never called it anything but “the woods.” Where have you been? my mother would ask. The woods. What’s in the bucket? Um, salamanders. Where did you get them? The woods. Who’s in the box? Um, a turtle. What’s that inside your shirt? Um, a snake. This wasn’t disapproving interrogation; she knew she was raising a zookeeper, an explorer of mud wallows, a feral primate, and her indulgence was heroic. What’s your plan for Saturday? I dunno, I’d say, I guess maybe I’ll go to the woods. In truth, I spent so much time there that eventually I needed remedial training in basketball.
• • •
MEANWHILE, closer to home, the walnut tree and I got to know each other better and better. Its fruit fell as heavy green globes, hefty as golf balls, excellent for throwing at garbage cans. Each globe was wrapped in a thick husk that could stain your hands nicotine brown with its juices. The smell was unforgettable—turpentiney but fresh. Inside the husk was a round nut with a rugose surface, hard as brick, and inside the nut was meat. The tree’s leaves were compound, with multiple leaflets attached in opposing rows down both sides of a wand-thin stem. In autumn my chores included raking those leaves and stems and gathering those nuts so that the lawn mower, on its last pass of the season, wouldn’t launch them like shrapnel. One autumn my parents and sisters and I made a project of harvesting them. The nuts were left to season in grocery bags until their husks dried and darkened. Then we cracked them with hammers and teased out the meat. Many hours’ work, wrapped in that fine walnutty aroma, yielded a small pile of meat fragments and an entire suburban family with hands dyed brown. Besides these various ministrations to the tree, I continued climbing it.
At one point, having outgrown the little-kids’ swing, I hung a trapeze from a higher limb. But I never built a tree house or defaced the trunk with a ladder-line of plank steps. Driving nails into this living xylem would have seemed barbarous, both to me and to my father, himself a great lover of trees. The tree in its unsullied state embodied all the stairway and structure that seemed necessary. Besides, a board shack furnished with old carpet and comic books and a flashlight, forty feet off the ground, was not what I wanted. What I wanted was a tree. When the urge struck me to daydream, or to pout, or to gaze out across the landscape, I went to the crow’s nest.
And there was a further attraction: I was an acrophile. I liked the scary thrill of attaining heights. Though I didn’t know it then, the walnut tree was my tiny midwestern substitute for granite spires and walls in the Sierra.
The tree’s lower reaches, though less thrilling and less solitary, weren’t neglected. As my balance became steadier, I took idle pleasure in tightroping on the two horizontal limbs. One especially, the tree’s right arm as facing the yard, longer and straighter and more bare than the other, made a nice sort of balance beam. I would walk out the length of it, some thirty feet, then hang and drop from a branch there, or else turn carefully and tiptoe back to the trunk. In summer I’d do it barefoot, getting a better touch of skin against bark.
At the time when this stunt amused me, I was no longer such a little boy. I must have weighed at least 110 pounds. I didn’t realize until recently what that extra load might have meant to the tree.
• • •
TREES ARE big creatures that live a long time, supporting vast weights of themselves at various splayed angles against the steady tug of gravity, the occasional burden of ice or snow, and the intermittent shoving and twisting of wind. As they compete with one another for sunlight, water, soil nutrients, and space, that competitive struggle goads them upward and outward. But craning upward and outward in midair isn’t easy. Beyond the basic ecological difficulties of survival, trees also face severe mechanical stresses—stresses that a jellyfish or a strand of kelp or a giant squid, living within the supportive medium of seawater, is never forced to endure. For a tree, standing high and dry, life isn’t so restful as it might seem. Great strength, supple resistance, and prolonged exertion are required. Imagine a chin-up that lasts a century.
A sizable body of scientific literature has developed in recent decades on the biomechanical design of trees. These studies concern patterns of limb and trunk structure and how those patterns reflect the imperatives of growth and survival. There’s a classic little book called The Adaptive Geometry of Trees, full of calculus and theory, published twenty-five years ago by a very fresh-minded biologist named Henry S. Horn. There are several interesting papers by Thomas A. McMahon, a professor of applied mechanics at Harvard. There’s an influential volume titled Tropical Trees and Forests: An Architectural Analysis, by Francis Hallé and two other scientists. As epigraph to their book, Hallé and his coauthors offer a quote from the venerable botanist E. J. H. Corner: “Botany needs help from the tropics; its big plants will engender big thinking.” The implied point is that Tropical Trees is not just about tropical trees but about the architectural principles common to all trees, as revealed most vividly in the tropics.
Why is the shape of a mangrove so different from the shape of a ceiba? Why is a baobab so different from a pandanus? Crossing back up into the north temperate zone, why is a pandanus so different from an elm or a maple? Why is a maple so different from a fir? Why is a fir different—noticeably, if not drastically—from a pine? The variety of shapes, and therefore the number of questions in this vein, might seem almost infinite. But the variety isn’t infinite, and some scientists have reduced its myriad particularities to a tractable number of generalized patterns. One authoritative source, Trees: Structure and Function, published a generation ago by two professors of forestry named Zimmermann and Brown, describes three basic tree forms: columnar, excurrent, and decurrent.
A columnar tree is one that rises in a single bare trunk, a column, topped off by a tuft of leaves. For instance, a coconut palm. Life is a little simpler and more limited in scope for columnar trees, due to the absence of limbs. An excurrent tree is one with a central stalk that predominates over a number of lateral branches, resulting in a cone-shaped profile. Most conifers are excurrent. A balsam fir carefully cultured and sheared for the Christmas-tree market embodies the very ideal of excurrence, its central stalk tapering up into an apical shoot to receive the terminal star or the glass angel. A decurrent tree shows a diffuse pattern of branching in which no central stalk remains dominant; instead, the trunk splits into a number of roughly coequal limbs fanned out through a full 180-degree arc, giving the crown a rounded profile. Maples, elms, hickories, oaks, and most other hardwoods are decurrent. The black walnut, Juglans nigra, is decurrent. If it weren’t, the crow’s nest I climbed to wouldn’t have been so far off-center, and the horizontal limb I walked back and forth on wouldn’t have been so stout.
