1493: Uncovering the New World Columbus Created (40 page)

Worse still, many researchers believe that the chemical assault is counterproductive. Strong pesticides kill not only target species but their insect enemies as well. When the target species develop resistance, they often find their prospects better than before—everything that had previously kept them in check is gone. In this way, paradoxically, insecticides can end up
increasing
the number of harmful insects—unless farmers control them with yet more chemical weapons. “Secondary pests,” insects that previously were controlled by some of the species killed off by insecticides, also profit. Here, too, industry has a solution: more pesticides. “A number of new chemistries are expected to appear on the market in the near future,” one research team announced in the
American Journal of Potato Research
in 2008. But

there is no reason to believe that any of them will break the seemingly endless insecticide–resistance–new-insecticide cycle that is so characteristic of Colorado potato beetle management.… Despite all the scientific and technological advances, the Colorado potato beetle continues to be a major threat to potato production.

Blight, too, has returned. Swiss researchers were dismayed in 1981 to discover that the second type of
P. infestans
oomycete, previously known only in Mexico, had found its way to Europe. Because the blight was now capable of “sexual” reproduction, it had greater genetic diversity—more resources, that is, to adapt to chemical control. Similar introductions occurred in the United States. In both cases the new strains were more virulent, and more resistant to metalaxyl, the chief current anti-blight treatment. No good substitute has yet appeared. In 2009, as I was writing this book, potato blight wiped out most of the tomatoes and potatoes on the East Coast of the United States. Driven by an unusually wet summer, it turned gardens all around me into slime. It destroyed the few tomatoes in my garden that hadn’t been drowned by rain. Accurately or not, one of my neighbors blamed the attack on the Columbian Exchange. More specifically, he charged that blight had arrived on tomato seedlings sold in big-box stores. “Those tomatoes come from China,” he said.

¹
Gerard did not contribute to a third source of confusion: the common practice of referring to sweet potatoes as yams. Yams originated in Asia and Africa and belong to yet another biological family.

²
Ralegh and his coevals spelled his name in many ways, including Rawley, Ralagh, and Raleigh. Although the last is most common today, he himself generally used “Ralegh.”

³
Supposedly one guest was Thomas Jefferson, then U.S. ambassador to France. He is said to have liked one potato dish so much that he served it in the White House. In this way Jefferson introduced the United States to French fries.

⁴
This comparison overstates the case. Compared to grains, potatoes have more water, which is nutritionally useless. In the past potatoes were about 22 percent dry matter; wheat, by contrast, was about 88 percent. Thus the 25,620 pounds/acre yield of potatoes found by Young was equivalent to 5,636 pounds/acre of dry matter. Similarly, wheat’s 1,440 pounds/acre yield would be 1,267 pounds/acre of dry matter. For this reason, it is fairer to say that potatoes were about four times more productive than wheat.

⁵
This may understate the impact. The historian Kenneth Pomeranz has argued that “some of the most intensely farmed soils of Europe (including in England) faced serious depletion by the early nineteenth century.” If guano had not arrived, Pomeranz believes, the consequences may not have been simply remaining at the same level but a full-scale disaster across much of the continent.

⁶
Reproducing both sexually and asexually sounds odd to big, clumsy mammals like us, but it is a canny survival strategy in much of the microworld (malaria-causing
Plasmodium
parasites reproduce both ways, for example). Asexual reproduction is useful in good times, because it produces offspring that are exactly as well adapted genetically to their environment as their parents. Sexual reproduction is valuable when the environment changes, because the sexual shuffling of genes creates variability, which helps the offspring survive in altered circumstances.

⁷
The campaign against lazy-bed farming may not have been reformers’ only contribution to destruction.
P. infestans
exploded across Europe so fast that one wonders whether the blight was accidentally distributed by human action. Ecological models suggest that blight is “more likely to be spread by people than by passive dispersal through the atmosphere.” At least one new product suddenly appeared in farms across much of Europe in the early 1840s: guano. On the passage from Lima to Liverpool, one can easily imagine blighted potatoes spilling from a broken barrel, spreading spores into the loose mass of guano in the hold. Blight spores can survive in soil for as much as forty days. If the soil were infected toward the end of the trip, that would allow more than enough time to distribute it. Ireland had been the site of much guano experimentation. By 1843, trials had occurred in at least eleven of its thirty-two counties. Farmers were swapping and borrowing samples with equal vim the next year. It is tempting to wonder whether
P. infestans
was less imported with the guano than imported
in
the guano. (Another pest, the potato cyst nematode, invaded Japan in exactly this way.) After the blight hit, some of Ireland’s most progressive farmers advocated a means for returning potato yields to normal: higher doses of guano. All through the Great Hunger the fertilizer ships came.

7
Black Gold

NO BIRDS OR INSECTS

It looked like a forest but ecologists probably wouldn’t call it one. It sprawled over miles of low hills outside the village of Longyin Le, at the southern tip of China, less than forty miles from the border with Laos. Prosperous by the standards of rural China, Longyin Le had houses with curtained windows and painted walls. Solar hot-water heaters and satellite dishes sprouted from the roofs on the houses beside the road. At the edge of the village the cab drove past barns and animal pens and then I was among the trees.

They were perhaps fifty feet tall and graceful to my eye, with mottled gray-green limbs and leaves that were pale on one side and glossy dark green on the other. All were of one species and all were the same age—forty-five years old, I had been told, give or take a year. That was when the government put them in the ground. With impressive thoroughness every other plant species that grew higher than my ankles had been cleared away. The effect was park-like, except that the trees, planted in rows about eight feet apart, created an almost unbroken canopy overhead. Spiraling down each trunk was a shallow incision the width of a knife blade. Stuck to the lower edge of the incision, following it down the tree, was a flexible plastic strip perhaps three inches wide. At the bottom of each spiral was a small ceramic bowl or a place to mount one.

The trees were
Hevea brasiliensis,
the Pará rubber tree. Villagers in Longyin Le had cut the bark and attached the strips as guides. A milky, sap-like goo
—latex,
from the Latin for “liquid”—emerged from the fissure and slowly dripped along the strip until it ran into the bowl. Depending on the tree and season, latex is as much as 90 percent water. Some of the remainder consists of tiny grains of natural rubber. At first hearing, “natural rubber” may sound like something sold in pricey New Age boutiques. In fact it is a major industrial product, highly desired by high-tech manufacturers. The natural rubber in
H. brasiliensis
had lifted Longyin Le and scores of neighboring communities from destitution.

After ten or fifteen minutes of driving I left the cab and wandered about. I had come to a slope ridged by low terraces, each bearing a line of rubber trees. Beyond the crest of the slope was a sharp drop-off, and beyond that were hills, irregular as the wrinkles of a sheet thrown to the floor, their colors fading with distance in the hazy afternoon. Every living thing that I could discern was a rubber tree.

The driver was walking with me. He said he had not been to this area since he was young. The hills had been full of mammals and birds then. All had been replaced by rubber. Even the insects were still. It may have been the quietest forest I had ever walked in. Every now and then there was a quick breath of wind and the leaves rippled like tiny flags, momentarily exposing their satin tops. “There’s nothing left,” the driver said, visibly upset. “People want to cut and cut and plant and plant—damn them.”

More than a century ago, a handful of rubber trees had come to Asia from their home in Brazil. Now the descendants of these trees carpeted sections of the Philippines, Indonesia, Malaysia, Thailand, and this part of China. Across the border
H. brasiliensis
was marching into Laos and Vietnam. A plant that before 1492 had never existed outside of the Amazon basin now dominated Southeast Asian ecosystems. Indeed, rubber reigned over such a wide area that botanists had long warned that a single potato blight–style epidemic could precipitate an ecological calamity—and, just possibly, a global economic breakdown.

Guide strips for latex and collection cups mark this rubber plantation in Xishuangbanna, China, an autonomous southern area near the Laotian border. (
Photo credit 7.7
)

In Longyin Le I wandered from house to house, talking to farmers about rubber. To a person they were thankful for the opportunities it provided. Rubber was putting food on the table, paying for children’s education, building and repairing roads. Just as the potato played a critical part in helping Europe escape the Malthusian trap (though perhaps only for a time), rubber had helped bring about the Industrial Revolution, the transition from an economy based on manual labor and draft animals to one based on mechanized manufacturing. The people in Longyin Le were its latest beneficiaries. As I looked over the lush miles of birdless trees I could still hear their grateful voices. And rising like vapor were other voices, the countless men and women whose lives, for better and worse, had become entwined with this plant: hapless slaves, visionary engineers, hungry merchants, obsessed scientists, imperial politicians. This landscape of alien trees was the creation of countless different hands in many places, and it was much older than forty-five.

“GREASE CHEMISTRY”

In May of 1526 Andrea Navagero, the Venetian ambassador to Spain, attended an entertainment in Seville staged for the royal court. Seven years earlier, Hernán Cortés, acting without the authorization of the Spanish throne, had invaded Mexico and toppled the Triple Alliance (Aztec empire). The king and queen had to decide what to do with their millions of new subjects. Some argued that they should be enslaved, because they were naturally inferior; others, that they should be converted to Christianity and made full citizens of Spain. To demonstrate the intelligence, skills, and noble demeanor of the peoples of the Triple Alliance, the antislavery faction of the Spanish church had imported a group of them to Seville. The Indians divided into teams and played a showcase version of the Mesoamerican sport of
ullamaliztli,
which the Venetian ambassador attended.

Navagero was an insatiably curious man who translated poetic and scientific classics, wrote a history of Venice, and performed biological experiments—he created a private botanical garden in 1522, among the first on the continent. He was mesmerized by
ullamaliztli,
which he seems to have thought was a performance akin to a juggling act (team sports had been played in the Roman empire but were then almost unknown in Europe). In
ullamaliztli
two squads vied to drive a ball through hoops on the opposite ends of a field—an early version of soccer, one might say, except that the ball was never supposed to touch the ground and players could hit it only with their hips, chests, and thighs. Dressed in padded breechcloths and wrist protectors like thick fingerless mittens, the players knocked a fist-sized ball back and forth “with so much dexterity that it was marvelous to see,” Navagero reported, “sometimes throwing themselves completely on the ground to return the ball, and all of this done with great speed.”

As fascinating to Navagero as the ball game was the ball itself. European balls were typically made of leather and stuffed with wool or feathers. These were something different. They “bounded copiously,” Navagero said, ricocheting in a headlong way unlike anything he had seen before. The Indian balls, he guessed, were somehow made “from the pith of a wood that was very light.” Equally puzzled was Navagero’s friend Pietro Martire d’Anghiera, who saw a game at about the same time. When the Indian balls “touch the ground, even though lightly thrown, they spring into the air with the most incredible leaps,” d’Anghiera wrote. “I do not understand how these heavy balls are so elastic.”

The royal chronicler Gonzalo Fernández de Oviedo y Valdés fared little better. In his
General and Natural History of the Indies
(1535), the first official account of Spain’s foray into the Americas, he tried to describe bouncing, a term not then in the Spanish language: “These balls jump much more than our hollow balls—by far—because even if they are only let slip from the hand to the ground, they rise much further than they started, and they make a jump, and then another and another, and many more, decreasing in height by itself, like hollow balls but more so.” Indians made the strange, springy material of the balls, he wrote, by combining “tree roots and herbs and juices and a combination of things.… [A]fter [the mixture] is dried, it becomes rather spongy, not because it has holes or voids like a sponge, but because it becomes lighter, as if it were flabby and rather heavy.” Wait a minute, one wants to say: how could something “become lighter” yet be “rather heavy”?

Europeans like German artist Christoph Weiditz were fascinated by the native ballplayers who toured Spain in the 1520s—and by the rubber ball, which was unlike anything ever seen in Europe. (
Photo credit 7.1
)

Navagero, d’Anghiera, and Oviedo had a right to be confounded: they were encountering a novel form of matter. The balls were made of rubber. In chemical terms, rubber is an
elastomer,
so named because many elastomers can stretch and bounce. No Europeans had ever seen one before.

To engineers, elastomers are hugely useful. They have tucked rubber and rubber-like substances into every nook and crack of the home and workplace: tapes, insulation, raingear, adhesives, footwear, engine belts and O-rings, medical gloves and hoses, balloons and life preservers, tires on bicycles, automobiles, trucks, and airplanes, and thousands of other products. This didn’t happen immediately: careful studies of rubber didn’t occur until the 1740s. The first simple laboratory experiments, in 1805, gave little hint that rubber might be useful—although the scientist, John Gough, did discover the fact, key to later understanding, that rubber heats up when stretched.
¹
Only in the 1820s did rubber take off, with the invention of rubber galoshes.

Take off for Europeans and Americans, that is; South American Indians had been using rubber for centuries. They milked rubber trees by slashing thin, V-shaped cuts on the trunk; latex dripped from the point of the V into a cup, usually a hollowed-out gourd, mounted on the bark. In a process reminiscent of making taffy, Indians extracted rubber from the latex by slowly boiling and stretching it over an intensely smoky fire of palm nuts. When the rubber was ready, they worked it into stiff pipes, dishes, and other implements. Susanna Hecht, a UCLA geographer who has worked extensively in Amazonia, believes that native people also waterproofed their hats and cloaks by impregnating the cloth with rubber. European colonists in Amazonia were manufacturing rubberized garments by the late eighteenth century, including boots made by dipping foot-shaped molds into bubbling pots of latex. A few pairs of boots made their way to the United States. Cities like Boston, Philadelphia, and Washington, D.C., were built on swamps; their streets were thick with mud and had no sidewalks. Rubber boots there were a big hit.