The Burning Season

by Andrew Revkin

  The class resumed its hike, and soon Daly had the familiar experience of coming upon a tree that he could not even place in a family, let alone a genus or species. It was time for the first arboreal ascent of the day. He sat down, unhitched his backpack, and pulled out a pair of tree-climbing irons—curved, pronged pieces of metal. He strapped them onto each foot with the prongs facing inward so that he could get up “where all the action is”—into the canopy. In the rain forest, it is only in the canopy, where the flowers and fruit are, that you can start to tell the trees apart. The trunks are often quite similar, frequently with a smooth bark that provides no easy foothold for parasitic plants. The leaves, too, are often nearly identical. Many rain forest trees, even those from disparate families, have oblong leaves with shiny surfaces and a sharp point called a drip tip; both features encourage rainwater to slide off the leaf quickly, keeping nutrients from leaching away.

  The tropical forest canopy poses harrowing challenges to the most adventurous of biologists. In addition to its great height, it is thick with marauding columns of ants, clouds of stinging wasps, and venomous spiders and snakes, among other pests. Investigators have tried to use systems of gondolas, catwalks, and pulleys—even hot-air balloons, which could be set down atop the canopy—but all of these strategies are either too dangerous, too limited, or too disruptive to the ecosystem to be of great use. Even so, scientists keep trying new tactics; one team in Panama has proposed using a construction crane to lower a gondola into the forest. But many still rely on that old standby—climbing.

  Daly started to clamber up a tree, ignoring a thin rivulet of ants. He had a loop of rope around himself and the tree and alternated moving one foot up, then rising, shifting the rope up, then moving the other foot. He had to ascend about 50 feet before he got to the first branches—and this was a small tree, whose top lay in the middle zone of the canopy. Daly had just about disappeared into the foliage when he found what he was looking for: a branch with fruit on it. A hack of a knife sent the branch floating gently to the ground. It was only later, when the samples were hauled back to Rio Branco, that the tree, with its small, tart orange fruit, was identified as Lacunaria, in the Quiinaceae family.

  Daly descended the tree and led his class deeper into the forest. Suddenly they came to a place where the shadows gave way to a blinding patch of sunlight. In the depths of a rain forest, it is easy to forget about the sun. The canopy, whose leaves have fifteen times the surface area of the forest floor below, efficiently catches most of the sun’s rays. As a result, the patch of light ahead—the result of a recent tree fall—was almost startling. Insects floated like white sparks against the surrounding black shadows. Daly and his students broke into dripping sweats as they clambered onto the broad trunk of the fallen giant and felt the day’s blast-furnace heat. Teetering along the trunk was the only way to get across the chaotic mass of thorny undergrowth. A false step surely would result in ripped flesh and a broken ankle. Here was the dynamic, unbalanced forest in action. Vines and runners and small shrubs were exploding in a tangle of photosynthetic action, sparked by the unfamiliar but welcome touch of the full intensity of the sun. Insects and animals were feasting on the verdant new shoots.

  Near the end of the day, as the class began to swing back through the forest toward the central compound, two students lagged behind and sat silently while the rest moved ahead along a trail. The forest closed in around them, and soon there were no human sounds. A breeze stirred some branches high above, and the slow, steady drizzle of leaves and flower petals turned into a shower for a brief moment. Vaguely, clouds could be seen drifting above the canopy. The occasional call of a rain forest bird echoed through the trees. A seringueiro bird sang its hypnotic, three-note song. It was a simple minor-key do-re-mi that was repeated at odd intervals and sometimes had an extra silent beat thrown in—do . . . re-mi. The tone was that of Pan pipes, ethereal, sourceless, and soft. Earlier in the day, several students had found themselves absentmindedly whistling an imitation.

  The puffy cumulus clouds grew taller and taller, as if someone were making an extra large ice cream cone. The clouds were growing as they always do in the afternoon, when the sun causes millions of tons of water to evaporate from the forest below. The evaporation from the leaves helps keep the forest cool, just as the evaporation of sweat from your body keeps you from frying in the summer sun. Distant, muffled thunder added to the faint music of the rustling leaves and bird calls and the steady trill of cicadas and other insects. Even in the dry season, sooner or later several of these mountains of mist always burst. Sure enough, a brief torrent of dime-size raindrops soon battered the canopy. Down on the forest floor, the rain was hardly perceptible. Almost all of the water was intercepted by leaves and branches and epiphytes. There is often a ten-minute delay between the time a downpour starts and the time water actually begins to hit the forest floor.

  As the shower passed, there was a scattering of high-pitched chirps from the canopy. But they were not from birds. A half-dozen slim, tan monkeys leaped through the treetops. “Saguinus labiatus,” said one of the students. These skilled climbers, with their prehensile tails acting as a fifth limb, sought their sustenance up where the sun was creating new growth.

  Then a different sound intruded, a distant, grinding roar that grew louder and louder. Gears clashed as someone fought with a truck’s balky clutch. Ten more minutes of walking brought the class to another blaze of sunlight. This time it was no tiny tear in the forest fabric, but a straight, sharp rip that started over a hill and disappeared toward the opposite horizon: a new road through the heart of the forest. It had been graded flat so that it ran through a shallow canyon as it cut across the variegated topography of that part of eastern Acre. A notched tree trunk made a ladder that the students clung to as they descended to the road.

  The pavement was black and broiling. The class crossed the road and picked up the trail on the other side. They spent another hour hiking through thickets and swampy spots and one remarkably tall stand of virgin forest that was dense with rubber and Brazil nut trees. They cut through a tangle of taboca—a spiny, bamboo vine —and drank some of the pure water that flowed from the slashes in the woody tubes. Eventually they made their way to the barracão and guzzled tepid soda.

  That night, in Plácido de Castro, they traded stories with the other teams over Antarctica beer and plates of rice, beef, fish, and beans. The mammal team had found seven different types of shrew-like animal in one acre and could not place four of them in a genus, let alone species. Others got out their botanical and wildlife guides and debated Latin names and seed types. As the researchers talked on, one of the exhausted boys who had been serving food and drink since six that morning suddenly grabbed a broom and started slapping at something on the wall behind Douglas Daly. It was a fleeting gray form about four inches long. With a quick lunge of the broom handle, the boy knocked it from the wall and then squashed it. One of the scientists who had jumped up gave it a quick look. “Phoneutria’ s the genus,” he said. “One of the most venomous spiders in Brazil.”

  The life ebbed out of the conversation. The mood had already been soured after someone brought up the subject of the blisteringly hot asphalt of the road they had come upon during their walk. Something about the shallow red canyon that the bulldozers had carved into the earth did not leave them. The students understood now why the seringal was run-down, why many of the scars on the rubber trees were growing over and others were encrusted with sun-cured ribbons of aging latex. They knew now why no stacks of rubber were seen on the veranda of the barracão. With the coming of the road, the owner no longer cared about a few tons of rubber or nuts. Now the value of the property would skyrocket, just as it had wherever a road had been cut into the forests of the Amazon, offering profits of 400, 600, and not uncommonly 1,000 percent. The future of those towering trees, the chirping monkeys, the Lacunaria, and the gongo was sealed. The road determined the fate of that land as assuredly as a diagnosis of AIDS dict
ated the fate of a man.

  Chapter 3

  Weeping Wood

  SINCE EUROPEAN EXPLORERS first confronted the daunting expanse of the Amazon, the region’s thick forests have been perceived as shielding a hidden treasure. The carving of roads into this tropical wilderness in recent decades has merely been a continuation of centuries-old efforts to exploit its presumed richness. The only people who made no effort to dominate the land were the Indians, who arrived some ten thousand years before the white men, spreading southward from the isthmus of Panama, sticking to the highlands first, then infiltrating the depths of the rain forest. Hundreds of independent Indian cultures evolved. Somewhere between three and five million Indians in all were scattered throughout the Amazon, hunting, fishing, cultivating pumpkin, corn, manioc, and many other crops, and harvesting cocoa, palm and Brazil nuts, medicines, resins, and other products from the forest.

  With a relatively low population density, they had little destructive impact on the surrounding ecosystem. Despite regular harvests, the rivers were still thick with turtles. Small plots were slashed and burned for farming, then intentionally abandoned to nature before the fragile soil was damaged. Deposits of charcoal have been found buried almost everywhere that scientists have looked, implying that much of the Amazon has burned at one time or another, but in small enough doses that the forest has recovered. In some areas, such as Pará in the eastern Amazon, unusually dense stands of Brazil nut trees are thought to have been planted by the Indians, supporting the theory that they were—and in some areas still are —sophisticated managers of the forest, not merely opportunistic gatherers. It was this lifestyle and ethic that were later passed on to the rubber tappers and formed the basis of the extractive reserves that Chico Mendes promoted.

  In the first half of the sixteenth century, when Europeans began to venture into the basin, the light touch of the Indians quickly gave way to the heavy hand of the conquistadors. After the conquest of the Incas by Francisco Pizarro in 1532, myths sprung up that the wealth of this Andean civilization paled beside that which might be found in the mist-shrouded forests to the east. There, an Indian kingdom with a capital called El Dorado was said to be ruled by a monarch who was anointed daily with fragrant oil, then dusted with powdered gold. He was reputed to bathe in a spring, the bottom of which was encrusted with gold dust that had washed from his body. The forests were fragrant with the coveted spice cinnamon. Pizarro’s brother Gonzalo, along with Francisco de Orellana, led an expeditionary force in 1541 down the eastern slope of the Andes to seek out and conquer this hidden empire and plunder it for spices and gold. The main force of the expedition was bogged down as it attempted to cross the frustrating network of rivers that covers the basin. Eventually, Pizarro was defeated by the jungle, which provided constant obstacles and little food. As the Spaniards resorted to boiling their belts and found their Indian bearers deserting, Orellana and a crew of fifty forged ahead on several small boats to find food. They never returned; later Orellana was branded a “despicable traitor” by Pizarro, who retraced his steps back to Peru.

  Orellana had continued downstream, making what turned out to be the first descent of the great river system by a European. It was this expedition that led to the name “Amazon,” after an account of the trip was published by Friar Caspar de Carvajal, who accompanied Orellana. Among myriad accounts of battles and extraordinary adventures—in which hyperbole and fact were inextricably mixed—he claimed that they had encountered fierce Indian tribes in which women directed the battle and clubbed to death any warrior who might be tempted to flee. As he recounted, “These women are very white and tall, and have hair very long and braided and wound about the head, and they are very robust and go about naked [but] with their privy parts covered, with their bows and arrows in their hands, doing as much fighting as ten Indian men, and indeed there was one woman among these who shot an arrow a span deep into one of the brigantines, and others less deep, so that our brigantines looked like porcupines.” The resemblance to the Amazons of Western mythology was noted, and the name stuck.

  Unfortunately, the shrubs containing a cinnamon-like essence were dispersed throughout the forest—following a pattern set by many plant species in the rain forest, where insects can overwhelm plants of one kind that are too closely packed. And no city of gold was ever found. That did not discourage future generations of explorers from hacking their way into the forests. It took more than two centuries for the myth to wear thin.

  The conquistadors were followed in the eighteenth century by the bandeirantes, Brazilian pioneers who fanned out from the southern city of São Paulo in search of slaves, gold, and simply the glory of expanding Portugal’s holdings. By the nineteenth century, the original concept of El Dorado had been tempered into a more figurative pot of gold; great profits could be reaped in the burgeoning trade in turtle oil, Brazil nuts, cocoa, fragrant oils and rare woods, and minerals (gold was finally found, although not in so convenient a form as the original explorers had hoped). Many forest products were brought to light by the hundreds of Indian cultures in the region. The Indians showed the white people the strong fibers of jute, the elastic gum called chicle, which formed the original base of chewing gum, and quinine, the first remedy for malaria. In his 1847 account A Voyage up the River Amazon, Including a Residence at Pará, the American naturalist William H. Edwards described the brisk river trade: “Coarse German and English dry goods, Lowell shirtings, a few descriptions of hardware, Salem soap, beads, needles, and a few other fancy articles, constitute a trader’s stock. In return are brought down balsam, gums, wax, drugs, turtle-oil, tobacco, fish and hammocks.”

  By the mid-nineteenth century, the Amazon had become a favorite collecting spot for “naturalists”—a new breed of scientist-adventurer. Most of them were self-taught generalists, eager to explore and classify the natural world and attempt to comprehend the laws governing its workings. Among this peripatetic band were Charles Darwin and Alfred Russel Wallace—whose intellectual competition would produce the theory of natural selection—Richard Spruce, and Henry Walter Bates. It was Edwards’s book that sparked Bates and Wallace, both in their twenties, to make their famous collecting foray to the Amazon a year later. After four years without serious mishap, Wallace sailed for England, but his ship burned and foundered. He himself survived, although his thousands of specimens and notes were lost. Bates returned to England after eleven years in the Amazon, with a collection totaling 14,712 species, 14,000 of them insects. Some 8,000 species had never before been described in Europe. Bates was paid the equivalent of 20 cents apiece for thousands of his insects; he estimated that he cleared only a few hundred dollars after more than a decade’s work —not that it mattered. The naturalists had come for biological riches, not financial ones. For this group, the Amazon was a different kind of El Dorado altogether. It was, according to Edwards, “the garden of the world.”

  Despite the increasing attention from both scientists and merchants, the Amazon remained a lazy, undeveloped backwater. Products were collected upstream by Indians and a scattering of ribeirinhos, families who settled along the river. The harvest then made its way to civilization via a tenuous chain of peddlers and middlemen. Almost nothing was cultivated, and then only for local consumption. There was no urge to develop the area because southern and coastal Brazil still provided enormous stretches of fertile farmland.

  The second great wave of change came over the Amazon late in the nineteenth century, all because of an inconspicuous tree whose only distinguishing characteristic is that it bleeds a milky white sap when its soft bark is scratched. The 100-foot-tall rubber tree, with waxy leaves and a soft bark, is a member of the euphorbiaceae family, which includes species ranging from manioc—the starchy root, also known as cassava or tapioca, that has spread through much of the tropical world—to the poinsettias that decorate shopping malls at Christmas.

  The exudate, called latex, is thought to have evolved as a protection against termites and other boring insec
ts. It flows through laticifers, fine tubules a half inch or so beneath the bark. When something invades the bark and breaks this layer—be it a termite or the blade of a faca de seringa—the tree immediately begins to bleed. Along with its gummy quality, which can quickly clog the mouth of an invading insect, the latex also has natural insecticidal properties. Like other plants that inhabit regions where nutrients are scarce and threats are many, the tree expends a lot of energy producing this chemical defense. It is analogous to a country’s defense forces—expensive and rarely used, but crucial to survival.

  Latex is a polymer of isoprene, which is a hydrocarbon, a molecule comprised solely of carbon and hydrogen atoms—just like oil, natural gas, and the cellulose making up this book. “Polymer” means that many isoprene units are linked together in chains. The fluid remains a liquid when the chains are short, but it starts to thicken when reactions with air and heat or the addition of chemicals cause more isoprene units to join a chain. In coagulated latex, the average is five thousand links per chain. These chains, in turn, are coiled, nested, and woven together; here and there, they are tacked to each other by weak bonds. The tight coils and cross links give a hunk of coagulated latex its remarkable elasticity. When tugged, the coiled molecular chains will stretch to more than twice their length, but the cross-linked chains ensure that when the tension is released, the molecules will revert to their original shape.