The chocolate tree: growing cacao in the forest can provide a living to small farmers and a habitat to diverse creatures
Robert A. Rice
To most North Americans the word “chocolate” probably conjures visions of a fragrant, nut-studded brown slab, or a box full of small but elaborate variations on gooeyness, or one of those outrageous dark desserts with names such as “mud pie” or “death by chocolate.” Few of us who savor and consume such delights think about moist, lush foliage, the shrieks of toucans and parrots, or a Maya ruler from the seventh century A.D. sipping chili-spiked cocoa froth.
But perhaps we should. Theobroma cacao–the tree whose grant pods contain the seeds that, when roasted and then ground, become the powder that is the basis of chocolate–is an evolutionary product of the vast tropical rainforests of the New World. Indigenous peoples domesticated the tree in the northern Amazon basin and seemingly independently somewhere in what is now southern Mexico, Guatemala, or Belize (recent genetic work, however, suggests that the Mesoamerican domesticated stock originated in South America). To those fortunate people, the cocoa drink made from cacao was, as reflected in the genus name, indeed the “food of the gods.”
Today, however, this forest tree is cultivated far from its birthplace. In 2002 more than 40 percent of the world’s cacao came from Cote d’Ivoire. Ghana, Indonesia, and Nigeria together produce about 33 percent, Brazil less than 5 percent. But though well-heeled norteamericanos may be laying down a ten-dollar bill to pay for half a dozen hand-crafted chocolate delights, the world’s average rate for cacao beans in 2002 was not much more than eighty cents a pound, and many farmers who grew the beans were paid far less.
Yet a look at the biology, history, ecology, and economics of the cacao tree–and the industry that has sprung up around it–shows that unlike many products of the developing world that the developed world enjoys, cacao can be a relatively benign crop. It can be grown economically on small farms, bringing individual farmers into the world’s cash economy without destroying their independence and self-determination. As a shade-tolerant tree, it can also be cultivated under a canopy of larger trees already living in the tropical forest; clear-cutting is actually detrimental to a sustained crop yield. That means that cacao growing, albeit not entirely without harm to the forest ecosystem, is far less destructive than most other forms of cultivation. Preserving the canopy, in turn, helps in maintaining populations of indigenous birds and other forest animals, and in pulling carbon dioxide out of the air. Inside the wrapper of this food we have come to take for granted is a complex web of interrelating factors that ecologists are only beginning to understand.
The cacao tree grows naturally in the shaded, humid understory of lowland tropical forest, reaching heights of some twenty feet. Twenty or thirty large, gently fluted pods grow directly from the tree’s trunk and branches, dangling like holiday ornaments. Each pod is between six and twelve inches long, its hue orange or reddish orange by the time it matures. Inside the pod are two or three dozen seeds–the cacao beans–surrounded by a sweet, milky-white gelatinous pulp that is the main ingredient for a South American drink.
The cacao beans themselves, which are dull brown on the outside and a striking purple within, are an unlikely resource for the dessert-hungry people of the world. A mere brush against the tongue imparts a strong and bitter flavor. The pods and their beans probably evolved as they did by taking advantage of the cravings of nonhuman primates. The sweet pulp is an attractive food, encouraging the animals to remove the pods. The beans, or seeds, however, are enriched with distasteful alkaloids, and thus are discarded wherever the pulp is consumed. The combination virtually guarantees seed dispersal.
The native cacao tree also depends on minuscule flies, attracted by the overripe pods that fall to the ground and rot around its base. The flies require large pieces of moist tropical detritus (such as rotting cacao pods) to carry on their own life cycle; while thus occupied, they pollinate the tree’s small flowers, which develop into the next generation of pods. Because of that natural history, cacao is much more likely to be pollinated in a forest with a moist, messy understory than in a commercial plot cleared or raked by human tools.
Cacao has been cultivated for hundreds if not thousands of years, and so has been subjected to plenty of ad hoc horticultural experimentation. Even before European contact, cacao trees had been planted far from their natural origins, and their beans were a treasured Mesoamerican re source. By the time of contact, according to the early sixteenth-century Spanish chronicler Gonzalo Fernandez Oviedo y Valdes, the beans had become so widely cultivated that they were used as money: to acquire “gold, slaves, clothing, things to eat and everything else,” Valdes wrote. Between the late seventeenth and the late nineteenth centuries, the heyday of Europe’s colonial empires in the tropics, cacao joined coffee and rubber as crops transplanted to distant shores.
All three of those transplants proved highly successful. They benefited, at least initially, from the enforced separation between the plant and its coevolved insect pests and diseases. Coffee, native to tropical Africa, is now grown for export in Brazil, Colombia, and Vietnam; rubber, native to South America, is cultivated in Malaysia. For cacao, the heavy-hitting region for production quickly became West Africa.
Like its sister crop coffee, cacao is still commonly grown in a forest or forestlike setting called an agroforest, where shade trees tower over cacao plants that have been pruned to harvestable height. Botanists classify such agroforests (at least for cacao or coffee) according to the stature and diversity of the shade-tree canopy. In “rustic” cacao farms, large canopy trees in the original tropical forest are thinned out, to enable more light to penetrate to lower heights. Cacao trees are simply cultivated beneath the remaining shade trees. This is in considerable contrast to the large, technologized “zeroshade” cacao plantations, which apply generous amounts of highly toxic herbicides, such as paraquat, and potent insecticides such as endosulfan.
But most cacao today is grown on so-called polycultural farms, under planted shade–a somewhat more managed environment than the rustic farms, but still far more biodiversity-friendly than the zero-shade plantations. In a polycultural system the farmer selects and manages much of the canopy, or even all of it. A single species, usually a fast-growing legume, supplies most of the shade. Trees that yield fruit for human consumption often form a second, intermediate canopy. Beneath it all are the low-growing cacao trees [see illustration on opposite page].
To be fruitful, a cacao tree must get individual attention–something the family farm and the small farmer are best suited to provide. Less than a third of the cacao flowers become fruit–in other words, pods–and the careful cultivator will remove defective pods throughout the growing season. Not surprisingly, hired hands on huge plantations are sparing with such tender loving care. Furthermore, large areas planted with a single crop give rise to serious agronomic problems of their own. The typical smallholder’s practice of growing cacao along with an array of shade trees reduces such difficulties.
Small and medium farms of all kinds are often more productive–in terms of total useful product per unit area of land–and cacao farms are no exception. There is no big secret about what makes that so. Small peasant producers simply must work harder and smarter if they are to survive. Tied to the land, with only the occasional chance to supplement their agricultural earnings with gainful off-farm labor, small farmers are highly motivated to anticipate (and, as much as possible, to mitigate) the risks of farming: natural forces such as weather, insect infestations, and disease, and human (but still uncontrollable) factors such as export-price fluctuations and societal upheavals.
Traditional rustic and polycultural cacao systems seem well suited to cope with such risks. Part of their success comes from diversification: the multi-layered forest yields not only cacao beans but also a cornucopia of other products. Farmers can harvest avocados, bananas, breadfruits, mangoes, and oranges, as well as medicinal plants, rubber, and timber. Harvesting wood from a traditional cacao farm has the added benefit of protecting other extant forests from the ax. And when cacao bean prices are low, a farm’s noncacao products can still supplement the household diet and generate cash at nearby markets. Finally, polycultural cacao farms that are abandoned when world cacao prices fall or disease attacks the trees may devolve into patches of secondary forest, a habitat that remains conducive to preserving biodiversity.
Today some 17 million acres worldwide are planted in cacao, an increase of 60 percent since the early 1960s–when the North American dessert choice was far more likely to be cherry pie a la mode than chocolate mousse. Production of cacao beans approached three million metric tons in 2002. On a global scale, about 90 percent of all cacao farmers are “small”–defined as holding less than twenty-five acres. In some nations, such as Ghana and Cameroon, “small” almost certainly refers to a farm of less than half that area. Plantation farming was particularly popular in Malaysia, where in the early 1990s total cacao acreage soared to 750,000. But large-scale farming proved unsuccessful, and so most of the country’s 125,000 acres of cacao today are small-scale farms.
In 1996 ornithologists announced the discovery of a new species of Neotropical ovenbird, the pink-legged graveteiro (Acrobatornis fonsecai), within the rustic cacao farms of the state of Bahia, Brazil. An endangered monkey, the golden-headed lion tamarin, had already been spotted in the same habitat. Those sightings were turning points for conservation biologists. After decades of focusing on pristine habitats, the biologists began to pay increasing attention to agricultural settings. Part of the shift came from their realization that, in many areas, agroforests and forest fragments are all that remain of the original, vast forestlands. Cacao farms quickly came to be regarded as preservers of biodiversity.
Surveys of the flora and fauna of rustic cacao farms in West Africa have been conducted since the 1950s, but the recent sightings of rare birds have brought new energy to the fieldwork. We and our colleagues at the Smithsonian Migratory Bird Center, as well as other groups working in Brazil, Central America, the Dominican Republic, Mexico, and West Africa, have consistently found greater diversity of species in the agroforests than we can document on other kinds of agricultural lands. Agroforests still harbor such forest species as bats, canopy birds, and migratory birds.
Compared with natural forest, of course, even agroforest lands are generally depauperate. The main casualties are tree species characteristic of old-growth forests. Such trees appear doomed to vanish because regeneration is unlikely wherever the understory has been highly altered. With their disappearance comes the disappearance of the coevolved fauna: large mammals and understory birds native to pristine forests are absent in the agroforest. For that reason, the rustic cacao farm is probably not an eco logically stable system. But the findings of the biodiversity surveys suggest that even some of the small-scale polycultural cacao farms offer shelter to many otherwise doomed forest organisms. Perhaps the best hope for the future is a polycultural system developed out of a combination of traditional practices and modern research, planted with shade trees that are valuable to wildlife as well as people.
For the past decade, those of us at the Smithsonian Migratory Bird Center have been surveying the composition and diversity of birds in southeastern Mexico, both in natural and human-created systems. Two quite different kinds of cacao farms are included in the survey. The first are small, rustic farms in a “buffer zone”–a belt of well-forested but still partly cultivated land–surrounding the completely uncultivated 1,300-square-mile Montes Azules Biosphere Reserve in the Selva Lacandona, a huge lowland tropical forest in the Mexican state of Chiapas. The second are small, polycultural, planted-shade farms in the lowlands of the state of Tabasco, on the coast of the Gulf of Mexico. The diversity of bird species we measured on the Selva Lacandona farms is more similar to what it is in pristine forests, or at least in forests that have been only slightly altered from their pristine state. Moreover, that diversity is between one and a half and seven times as great as it is in pastoral, open, or other more traditional agricultural habitats. A quarter of the most common species–mostly forest-breeding birds, both resident and migratory–occur both in the Lacandona agroforest and in undisturbed tropical forest.
In contrast, unfortunately, Tabasco’s polycultural farms support substantially fewer bird species than do the rustic farms–eighty-four compared with 142. We found virtually no forest-breeding species on the polycultural farms.
We and our colleagues have also conducted extensive surveys on the cacao farms in the Apurimac valley of south-central Peru, an area known for its production of alkaloidal crops: coffee, cacao, and coca (the last grown for both legal and illicit markets). Several decades ago, much of the low-elevation, shade-grown coffee land was converted to cacao production and then, in an attempt to control a fungal disease known as monilia pod rot, the shade canopy was removed. Years of civil war involving the Shining Path guerrilla movement left much of the zero-shade cacao abandoned. Today the area is dominated by tall scrub, particularly cacao, much of which is being brought back into production.
The Apurimac valley had been notable for both the diversity and uniqueness of its bird populations. We were disheartened, therefore, to sight only ninety-three species of birds (a low figure by Peruvian standards), all of which are commonplace even in disturbed habitats. Presumably even though our study area encompassed small fragments of forest and was only a few miles from more continuous stretches of woods, the many years of zero-shade cultivation had rendered the habitat inhospitable to the endemic birds. They may never return.
If cacao–appropriately grown–can do good things for biodiversity, what can biodiversity do for cacao? Both planned and unplanned diversity–what farmers put in place, as well as what just shows up–contribute to the crop’s successful cultivation, often in ways biologists don’t yet understand. Recent experiments with shade-grown coffee have shown that birds remove more than 70 percent of the arthropod population both from the canopy and from the understory crop plants. That number includes at least half the herbivorous insects. Ants play a complex and less well understood role: they are major predators on other arthropods, including many herbivores, but they also protect scale insects, which harm plants by living off plant juices.
Biodiversity on a cacao farm also includes towering shade trees, whose leaf litter slowly releases nutrients back into the soil, and offers an attractive habitat to a host of organisms that may be critical in the breakdown and recycling of the nutrients. If the shade trees include legumes, as is the case in many polycultural cacao farms, bacteria that live symbiotically in their roots supply the soil with usable nitrogen. The shade canopy also shields understory plants from the relentless tropical sun, as well as from the physical impact of driving tropical rains, thus reducing soil erosion. The diversity of species that follows from the presence of shade trees undoubtedly helps control certain pests and pathogens as well; taken together, the elements of the system embody the ecological mantra that diversity enhances stability. It is also worth noting that crops grown under a range of shade-tree species support substantially greater local diversity than do those grown under a single such species.
There is an even broader benefit from the massive shade trees that are an integral part of a rustic or polycultural cacao farm. They effectively sequester, or capture, carbon–acting as carbon “sinks” that shunt atmospheric carbon dioxide into fixed sites. That helps alleviate the buildup of the greenhouse gases in the atmosphere that are causing global climate change.
Historically, cacao itself has been a vagabond crop. Production levels have always been maintained largely by exploiting new forest frontiers worldwide. According to the botanist Francois Ruf of CIKAD, a French organization devoted to agricultural research for developing countries, the cycle begins as new forest is cleared. Seedlings are then planted that can take advantage of the cost-free nutrients in the soil of the newly cleared plot of land. With time, though, the cacao yields decline, until eventually the plot is abandoned. Then the “cocoa cycle” begins once again, on another patch of untouched forest.
In that way, as the worldwide craving for chocolate has grown, the unfettered forces of production have continued taking huge bites out of tropical forests around the globe. With no national guidelines–much less a global, or at least industry-wide, policy–to address the hungry advance of cacao into natural forests, some of the very forests that have served as raw material for cacao production in the past 200 years will soon disappear.
It is true that, in global terms, cacao accounts for a small fraction of forest degradation and clearing at any given moment. Yet the impact of such production methods in particular areas, such as West Africa and the Indonesian island of Sulawesi, can be substantial, and where clearing targets forest that harbors endemic species, the threat to biodiversity can be great. Furthermore, if production continues to be concentrated in particular frontier regions, the crop becomes increasingly vulnerable to new fungal diseases. Geographical diversification can help maintain the supply, but eventually a long-term vision is needed.
Some large companies have accepted responsibility for taking that long view, and have begun to fund research on natural agents that could control some of the diseases that plague cacao trees. There is a growing realization that maintaining cacao as an environmentally and economically sustainable crop is inextricably linked with the well-being of the hundreds of thousands of small farmers who tend the crop–and hold the key to future supply. And for small growers, biological methods of controlling disease are far more affordable–and far safer–than the expensive, environmentally detrimental chemicals so often applied by the owners of monocultural plantations.
Along with the recognition of the importance of the small farmer, a consensus is emerging among ecologists, economists, experts in economic development, and industry-based investigators that agroforestry, employing a diverse shade canopy, is the cornerstone of sustainable cacao farming. In Brazil’s cacao zones, recent planting schemes have been incorporating multiple species of shade trees, native forest species, and hardwoods or other economically valuable crops such as palms or bananas, all of which can increase the cacao farmer’s income and diversify the farmer’s product.
Certain enduring problems have relatively simple solutions. In Indonesia, for instance, the early harvest of the pods has reduced losses from a moth pest. Other initiatives are more complex. In Peru, treating the trees with certain plant-dwelling microorganisms, as well as with ecologically benign fungi that parasitize other fungi, has cut infestations of the witches’-broom fungus by 50 percent, and yields have increased by 20 percent (those programs, funded by Mars, Inc., of Hackettstown, New Jersey, draw on the resources and expertise of the U.S. Department of Agriculture). Scientists at the Smithsonian Tropical Research Institute have begun to identify some fungal endophytes–species that grow within plant tissues–that when present in cacao leaves and fruits may serve as natural biological controls against other fungi, such as those that cause the devastating disease known as black pod. Private chocolate interests have sponsored projects that link grower groups with disease experts and are funding research whose findings will be published in scientific journals.
But the economic factors that affect cacao farmers are less easily controlled. Cacao is a poor farmer’s crop, and the pluck and perseverance of the growers who migrate to remote areas to carve out a livelihood are rarely rewarded with fair prices. No matter how well they anticipate adversity, they are constantly buffeted by market fluctuations in the price of cacao beans, driven by forces far away from the farm. A good example is last fall’s surge in world cacao prices to eighteen-year highs, about $2,500 per metric ton, caused in part by civil turmoil in Cote d’Ivoire. Yet at the same time in neighboring Ghana, where the government sets the price growers receive, farmers had to settle for just $763 a metric ton–70 percent less than the market rate.
Thus the fundamental issue of what the grower gets paid remains unsolved. Activists in the “fair trade” movement have convinced some of the major players in the chocolate industry that price has to cover the true costs of production by the small farmer and provide a living wage to the farm family. Several industry giants are now buying cacao at a higher-than-market price from associations of small growers; part of the money then goes toward community development and the implementation of sustainable production techniques. And several smaller but quite upscale companies are working directly with producers to showcase their cacao beans in certified organic chocolate products.
So the next time you order chocolate mousse, topped by a few shavings of bitter chocolate and a dab of whipped cream, think of it the way you might think of homemade strawberry jam, or hand-rolled sushi, or a top-flight French wine–something that’s worth paying extra for. Chocolate, too, at least at the grower’s end of the production chain, remains a cottage industry: the work of many hands, by people who have to pay their own bills. And then, because you truly enjoy it, savor their work.
ROBERT A. RICE (“The Chocolate Tree,” page 36) (far left) works predominantly on issues of tropical agriculture and land management. A geographer and policy researcher at the Smithsonian Migratory Bird Center in Washington, D.C., Rice helped organize the Smithsonian’s first workshop on sustainable cacao production. His coauthor, the ornithologist RUSSELL GREENBERG, investigates the ecology of the migrant birds that winter in Latin America’s human-dominated landscapes, such as coffee farms, cacao farms, and cattle pastures. Associated with the Smithsonian Institution for nearly thirty years, and director of the Smithsonian Migratory Bird Center since 1992, Greenberg helped launch conservation initiatives such as the Smithsonian’s bird-friendly coffee program.
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