The Tree (21 page)

But the seeds of destruction had already been sown, literally, before Manaus was even built. In the 1860s Sir Clement Markham of Britain’s India Office, who had already organized the introduction of
Cinchona
(for quinine) from tropical America to plantations in India, sought to do the same with
Hevea.
Botanists from Kew soon established that
Hevea brasiliensis
was the best of the genus. Eventually, in March 1876, Henry Wickham brought seventy thousand seeds of
Hevea brasiliensis
from Brazil to Kew, where just over two thousand of them germinated. From Kew young plants were sent to Ceylon (now Sri Lanka) and Malaya (now Malaysia). Soon the Asian plantations were the world’s major producers. Their only real setback since then has come from the rise of synthetic rubbers, first developed in America during the Second World War, when the Japanese occupied the principal rubber plantations of the East; the U.S. synthetic-rubber program was second only to that of the atomic bomb. By the 1980s, natural rubber filled only 30 percent of the world market, but by 2002 it had sprung back to 40 percent. Perhaps this is part of a general world shift from industrial chemistry to biotechnology. But natural rubber still fills various special niches—for example, in airplane tires and in condoms.

Brazil now produces far less rubber than Malaysia; for one thing, its plantations are beleaguered by an untreatable fungus called South American leaf blight, which those of Asia have escaped. But for Brazilians, rubber is still of immense cultural importance. The rubber tappers’ movement in Acre in the 1980s did much to draw the attention of the West to the plight of the Amazonian forest. Overall, Brazilians continue to smart at what they see as the theft of their inheritance. Some argue that Henry Wickham did nothing underhanded. At least, he declared his cargo to the Brazilian customs officers as “exceedingly delicate botanical specimens specially designate for Her Majesty’s own Royal Gardens at Kew”: disingenuous to be sure, but not inaccurate. Others see the entire episode as biopiracy. All in all, it does seem most unjust, but this is a tricky area. After all, the Brazilians are doing very well with eucalyptus, which Europeans brought from Australia in 1828 (though it has not always been planted wisely and in places is a serious pest). Brazil is also pushing ahead vigorously with teak, from India. Its biggest agricultural export these days is soya—a Chinese plant. Brazil’s cattle originally came from Europe (and to some extent from India). For their part, the Chinese grow enormous quantities of potatoes and maize, which are American, and wheat, from the Middle East. Deciding who has a right to what is a key issue of present-day politics and globalized commerce. (More in Chapters 12 and 14.)

On more practical matters: plantation rubber trees generally start producing useful amounts of latex at around seven years; are producing maximally by age fifteen; and are generally chopped down and replanted after thirty years (when they are about 20 meters tall). So the grower has about twenty-three productive years out of thirty. In the past the timber was simply burned, but it is a pleasing reddish brown and strong, and in recent decades has become a major crop. Malaysia and Thailand now export nearly $1.5 billion worth of rubberwood furniture. Southeast Asia could harvest more than 6.5 million cubic meters of rubberwood per year—almost as much as the entire timber harvest of Central America.

In Malaysia I found the rubber plantations in many ways attractive: green and aromatic shade in a colonnade of trunks, and all as cool as Sussex. But the work—slashing the bark every day and replacing the receptive cups—is desperately tedious, and recruitment of labor is difficult. My solution would be to make the work more interesting—by integrating smaller plantations with mixed farming, as I have seen in China. Indeed, rubber trees do lend themselves to agroforestry. Other crops (including valuable herbs) may be grown among them, and their shade is good for livestock. As a bonus, they produce big, oily seeds—which are thrown spectacularly for several meters as the fruit dries and splits. In the wild, in Amazonia, these seeds are dispersed by large river fish. In plantations, I would have thought they would be ideal for turkeys. I would hate to be a traditional rubber tapper, and I feel sorry for those who are (in Malaysia, their daughters take off for the electronics factories). But a mixed exercise in agroforestry, with other crops and livestock, is a different proposition all together. A grand challenge: most interesting.

Then there are the Rhizophoraceae—the family of
Rhizophora,
the red mangrove trees. Mangrove forests grow at the edge of the sea throughout the tropics: in northern Australia, Southeast Asia, western Africa, around the Red Sea, along the north coast of South America, on both coasts of Central America, and in the Caribbean. Although mangroves occupy only seventy thousand or so square miles of the earth’s surface, they are hugely important ecologically and economically. Around their roots breed a host of sea creatures, including many ocean fish. Local people take as much from the mangrove forest as forest people take anywhere—fuel, timber, fruits—and fish, too. Offshore from the mangroves, typically, are the sea grasses—food for fish, mollusks, manatees, and marine iguanas—and beyond them lie coral reefs, which in diversity of wildlife are second only to tropical forests. The mangroves, if left intact, protect the sea grasses and the reefs. Since the mangroves, sea grasses, and corals are all nurseries for marine creatures, the consequences of mangrove destruction extend through all the oceans. Yet they are being destroyed—to make way for marinas and promenades, for lagoons to raise tropical shrimp for Western supermarkets, and even, it sometimes seems, just for the sake of it. In Panama in 2003 I was shown a mangrove that had been filled in with rubble to provide a park for containers, of the kind used for oceangoing cargo ships. The local government bought the idea from some entrepreneur on the grounds that it would provide employment. The only employee when I was there was a man with a gun, to keep people off. The entrepreneur, having pocketed the taxpayers’ money and destroyed the mangrove forest (and the wild creatures, and the livelihoods of the people who were living there), was about to sell his barren dump to the Chinese. That’s business, apparently.

To return to the natural and saner world: about eighty species of trees have mastered the adaptations needed to live in the intertidal zone. Of these, thirty or forty are core species that turn up in most mangrove forests; and of these the most important overall are seven or eight species of
Rhizophora.

The third great arborescent family of Malpighiales is the Salicaceae. It is named for the genus
Salix,
the willows. There are about 400 species—although as outlined in Chapter 1, they are hard to identify and very prone to hybridizing, so it will always be effectively impossible to say exactly how many there really are. They range from small shrubs to big trees, and from the tropics to the extreme north. Up cold and windy mountains, and on the edge of glaciers up toward the Arctic, they are often the chief woody species. In such territory, they send out underground stems to form vast clones: a wood that in effect is a single plant. Thus the creeping willow,
S. repens,
colonizes marshland and begins its transition into forest. Most willows like the edges of rivers, where they are commonly planted to stabilize the banks. They may serve, as reed beds do, to purify the water. Some are ornamental: the original weeping willow in particular,
S. babylonica,
originated in China, drooping languidly over lakes and lazy rivers as if specifically intended for patterned tea sets.

Willows belong in the Northern Hemisphere, although one
(S. mucronata)
crosses the equator in Kenya. Many kinds live in western China, which is truly one of the world’s great centers of diversity; but, like so many trees, these Chinese willows have not yet been properly studied. Willows are nearly all dioecious (males and females on separate plants) and produce catkins that are usually pollinated by insects, although wind probably plays a part. Their seeds are tufted and float on the wind. The different forms of willow find many traditional uses: the thinner twigs (especially of osiers,
S. viminalis
) for baskets, coracles, and hurdles; the bigger timbers for construction. Female clones of
S. alba
var.
caerulea
are the sole source of wood for cricket bats (though sadly threatened from time to time by the bacterium
Erwinia salicis
). The finished cricket bat is a botanical extravaganza: white willow for the blade, bamboo and rubber for the handle, plus twine to bind the handle and glue to hold it in the blade, both of which may come from plants, and linseed to keep the bat supple. Willow is also an important fuel wood, now much vaunted as a source of biomass to supply energy without exacerbating global warming. Finally, the bark of willow is particularly rich in salicin, the root molecule of salicylic acid, the stuff of aspirin—of proven use as an analgesic and anti-inflammatory, and now favored to reduce blood clotting and guard against thrombosis.

Also in the Salicaceae and closely related to willow is poplar
(Populus),
the twenty-nine or so species of which include the aspens, like North America’s quaking aspen,
P. tremuloides.
Poplars are hugely favored for plantations worldwide, for matchsticks and paper pulp. They also serve as windbreaks and (like eucalypts) help to dry out wetlands, acting like wicks. A major task now is to conserve their genetic diversity, as the wet river banks that they favor are drained and contained. The levees of the Mississippi have greatly reduced the natural regeneration of the native
P. deltoides.
Attempts are afoot worldwide to conserve the diversity in arboretums. In Europe, EUGORGEN, the European Forest Genetic Resources Programme, is intended to conserve the natural diversity of the black poplar,
P. nigra,
and holds nearly 2,800 clones from nineteen countries. In the Pacific Northwest, GreenWood Resources holds one hundred stands of
P. trichocarpa,
to counteract the losses along the Columbia and Willamette rivers and their tributaries. Efforts to conserve poplars in situ include the Tarim River nature reserve in the Xinziang autonomous region of China, largely intended to conserve the remaining third or so of the original
P. euphratica,
and a plan supported by the International Poplar Commission and the United Nations to conserve the native variety of
P. ciliata
in the Himalayan foothills of India. Such efforts are heartening.
Populus,
however, is only one among many thousands of genera of trees, and the vast majority are receiving no help at all. Even if they escape extinction, few will escape severe genetic diminishment.

There are some other notable Salicaceae too—including some that are traditionally placed in the Flacourtiaceae, which Judd enfolds within the Salicaceae. Among them are the Maracaibo boxwood,
Gossypiospermum praecox,
from Cuba, the Dominican Republic, Colombia, and Venezuela—highly favored for specialist tasks, not least for the working parts of pianos, and odoko from West Africa, species of
Scotellia,
hard and tough and excellent for floors.

Several other families in the Malpighiales are worth a passing mention. The Violaceae in temperate regions manifests as herbs, including violets; but in the tropics it produces some fairly mighty trees. The Malpighiaceae, for whom the order is named, include the Barbados cherry. The Clusiaceae are best known as the family of Saint-John’s-wort, which finds favor as an antidepressant. But it also includes some handy trees—not the least being the 200 or so species of
Garcinia,
which include the mangosteen,
G. mangostana,
a native of Malaysia with fruits the size of a Ping-Pong ball, whose brownish-purple leathery skins enclose treacly and truly delicious (I can vouch) creamy-white segments. An excellent fruit, though the trees are slow-growing and not easy to cultivate.

The Ochnaceae family includes the ekki tree from West Africa,
Lophira alata,
from whose timber (for some reason) the tracks of the Paris Metro are made. The Metro trains have rubber tires. I venture that few who ride the Paris Metro realize their debt to the trees of the Malpighiales.

S
TAR
F
RUIT AND
C
OACHWOOD
: O
RDER
O
XALIDALES

The Oxalidales is yet another order that has been subject to serious reclassification. The family for which the order is named, the Oxalidaceae, is primarily tropical and subtropical and is known to northerners primarily through wood sorrel
(Oxalis acetosella).
It does include a few small trees, however, one of which is the star fruit or carambola,
Averrhoa carambola.
The fruit is juicy, sometimes sweet and sometimes acid; is deeply ribbed and thus star-shaped in cross section; and has lately become fashionable outside its native Indonesia. Modern DNA studies also place the Cunoniaceae within the Oxalidales; these include
Ceratopetalum apetalem,
a tall (18 to 24 meters) and valuable timber tree from New South Wales known as coachwood (or lightwood or scented satinwood). Its browny-pink, fragrant timber is used for lots of things, especially joinery and moldings, but also for gunstocks, shoe heels and musical instruments. Thus the wood sorrel emerges as yet another homely herb with wildly exotic relatives.

T
REES FOR
F
ODDER
, F
UEL
, F
LOWERS
,
AND
B
EAUTIFUL
T
IMBERS
: O
RDER
F
ABALES

Within the Fabales order are four families, but the only one that need delay us is the Fabaceae—and they should delay us plenty because, together with the grass family, Poaceae, the Fabaceae is the most important plant family of all, both ecologically and economically. It is also the third largest, with 18,860 or so known species in 630 genera, but the inventory is still rising fast. Only the orchids and daisies have more species. Fabaceae used to be called Leguminosae—the pods are called “legumes.” The old family name is now officially defunct but the adjective “leguminous” and the informal noun “legume” (applied to the whole plant as well as to the pods) live on.