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2 CHOCOLATE BERRIES Of the nearly 70 Vitex species found scattered across tropical Africa, at least some are of local commercial and nutritional importance. These small and rugged trees are quintessential wild foods. In season, they become bespangled by an abundance of blackish fruits, which passersby eagerly gather up. Part of the harvest is eaten there and then, but most goes to market for sale. The reason? Although newcomers may loathe the pungent scent and brown stain on the lips, almost everyone loves the “chocolate” flavor. Unknown beyond Africa, these particular Vitex species, from the mint family (Labiatae), are essentially unknown to science too. But they are so useful that without them life would be even harder in many places between Senegal and South Africa. You see, villagers rely on these trees for much more than just fruits. They boil and eat the young leaves like spinach.1 They depend on the foliage to keep their livestock from starving during the long and trying months when the grass is gone. They use the twigs as chewsticks to clean their teeth. And they visit the trees to obtain medicines.2 Beyond all that, these supremely utilitarian species produce a straight- grained timber resembling teak. It is used for the walls and roofs of houses as well as for furniture, boats, crates, bowls, stools, shelves, and (at least in Uganda) chairs, drums, and knife handles. It also makes good firewood and is said to be good for rubbing together to start a fire by friction. For all these reasons, these rugged, robust, and resilient woody plants seem excellent candidates for further development and more organized use. They are obviously not solely horticultural resources: their greatest value, eventually, may be not to fruit growers, but to livestock owners and to foresters. For this last, they are especially promising because people eagerly plant and tenderly nurture any quality seedlings supplied. Everyone likes The resulting food is called dinkin in Hausa. 1 This may not be without merit. In 2001, the British Medical Journal (BMJ 322:134-7) 2 reported on the effects of extracts from the fruit of the “chaste tree.” In the study, 170 women took this preparation over three menstrual cycles. More than half showed less irritability, anger, headache, and breast engorgement—classic manifestations of premenstrual syndrome. The study’s authors speculate that the tree has hormonal properties and also acts directly on the brain. Its scientific name: Vitex agnus-castus. 235

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LOST CROPS OF AFRICA 236 Central African Republic. A chocolate berry (species unidentified) locally known as mbili. (Roy Danforth and Paul Noren) having a chocolate berry tree3 around. Some already go out, gather the seeds, and deliberately plant their own. For such reasons, these species likely have exceptional promise in agroforestry and rural reforestation, and they might perhaps become standard components in the mix of species employed to stabilize eroding slopes and abandoned wastelands across much of the continent. Among other advantages is their longevity. These trees are never cut down irresponsibly. Even the wild ones are protected by societal rules. Those traditional rules have a good social purpose. Almost everyone— not to mention the environment—benefits from the living trees. But certain people benefit more. An example is livestock owners, for whom the trees’ ability to stay green far into the dry season has a vital appeal. When grasses shrivel away to nothing these trees, whose roots tap into moisture reserves far below the grass’s reach, stay green. That is a feature particularly appreciated by anyone facing loss of livelihood when the fodder runs out. In addition, the living trees are renowned among honey hunters. The flowers attract bees from long distances. Indeed, beekeepers deliberately seek out the trees and hang their hives among the branches. Furthermore, a hollowed-out chocolate-berry trunk makes a most favored beehive. There is no collective common name for these fruits. “Chocolate berry” has in the past 3 referred only to Vitex payos, but for purposes of this chapter we have co-opted the name to refer collectively to the various African Vitex species with promise as fruit trees. It is not a perfect match, given that botanically speaking the fruits are not berries but drupes.

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CHOCOLATE BERRIES 237 Little is presently known of the nutritional contributions, but the fruits seem likely to be excellent foods. In Sierra Leone they are claimed to cure a condition associated with sores at the corners of the mouth and eyes. That particular condition is most likely a nutritional deficiency caused by lack of vitamins A and B. Despite the baffling dearth of technical data, these are almost certainly promising resources. Having more chocolate-berry trees would likely benefit Africa’s many economies, people, livestock, wildlife, and general environment. Anyone developing sustainable agriculture or raising rural incomes or reducing environmental degradation should consider planting, protecting, and promoting these species. Clearly, appropriate authorities should engage themselves in the process of moving Vitex species into greater production. Specific opportunities to advance these small rugged trees are legion. There are, for example, tasks here for sociologists, anthropologists, village leaders, NGOs of various kinds, government researchers, students, professionals, schoolteachers, and more. Building projects around any of these species might involve: • Making better use of the local wild plants; • Documenting traditional usages; • Selection of elite specimens; • Horticultural development; • Plant physiology and botanical studies; • Food technology; • Nutrition research and feeding trials; • Marketing and economic development; • Publicity and promotion; • New plantings; • Financial support for humanitarian or environmental benefit; and • Coordinating cooperation and education through websites or newsletters. Although all 70 Vitex species might be worth investigating, we highlight below 7 seemingly representative examples. Black Plum Tallest, most common, and best known of Africa’s chocolate berries, this tree (Vitex doniana Sweet)4 produces purple-black fruits that are sweet and mealy. Most of the time they are eaten merely as snacks, but sometimes—notably during the rainy season—they turn into family staples, not to mention profit centers. During that time in Mali—to mention just one country—thousands of women and children go out and collect the fruits to sell in the marketplace. When ripe, the fruits fall from the tree and (because Synonyms are Vitex cuneata and Vitex cienkowskii. 4

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LOST CROPS OF AFRICA 238 Mature Vitex doniana tree near Jinka town, South Omo, in southern Ethiopia. (© Erick C. M. Fernandes, ecf3@cornell.edu) neither the impact nor the soil dampness does any damage) they are usually picked from the ground rather than from the tree. Black plum grows wild throughout tropical Africa: from Senegal to Angola, including the Congo basin, Sudan, Uganda, and Zambia. It is a much-branched, rounded tree ranging in height from 10 to 25 m. In nature it occurs mostly in coastal savannas, savanna woodlands, and secondary deciduous forests. Though the species is not truly domesticated, throughout West Africa it is found growing in villages. Some of the trees there were deliberately planted, but most were retained when the land was cleared. Olive-shaped and black when ripe, the fruit has prune-flavored pulp. It can be eaten fresh like plums or dried like prunes. It is also suitable for processing into jams and jellies. A kind of black molasses as well as various

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CHOCOLATE BERRIES 239 5 sweetmeats are made as well. The roasted fruit gives a coffee-like beverage. The fruit, however, is just a beginning of this tree’s utility. Indeed, black plum is so useful it has been described as “practically a department store on a trunk.” Beyond the sweet-tasting fruits, the young leafy shoots are also popular. They are boiled up and eaten like spinach. The flowers attract so many bees that beekeepers fight over who gets to hang their hives among the branches. The foliage provides fodder for goats, sheep, and cattle. And the tree provides medicines. A bark decoction, for example, is applied to skin diseases and aching teeth, and the leaves are used to treat diarrhea. To date, little has been done to regenerate this species artificially. However, in preliminary investigations Nigerian researchers have found the black plum propagates easily.6 It can be planted by direct seeding (preferably after piercing the hard seedcoat so water can pass through). It can be raised in a nursery and transplanted as seedlings, bare-root or potted. And it regenerates naturally by coppice and root suckers, so that vegetative propagation should be readily achievable. This important step, the critical one allowing superior types to be replicated, is probably the key to this species’ future as a fruit crop. Vitex grandiflora Turcz. Much like the black plum, this West African species is common in deciduous and secondary forests from Gabon in the east to Guinea in the west. It is a shrub or sometimes a tree (to 13 m high) with spreading branches. The yellow fruit, about the size and shape of an olive, turns jet black when ripe. Although the pulp is thin, it is made into sweetmeats like those made from the black plum. In Lagos, and probably elsewhere, an alcoholic beverage is made from the fruit. Aficionados liken it to Caribbean rum. Termite resistant and durable, the wood is valued for making houses, drums, and utensils. It finishes well and has at times been exported to Europe as a top-grade cabinet wood. Vitex simplicifolia Oliv. A small tree reaching not much more than 5 m, this West African species7 is common in savanna forests of Ghana, Mali, Togo, and Cameroon, and is to be found as far to the east as Sudan and Egypt. The flowers are greenish and violet. As in related species, the fruit is olive sized, purple-black, and cupped in a calyx like an acorn. The thin pulp clings to the stone, which contains 3 to 4 seeds. The leaves yield an essential oil of such sweet and penetrating fragrance that it is recommended for commercial development.8 In Hausa, these sweets are known as alewa. 5 Propagation by budding is successful. Information from J.C. Okafor. 6 This species is also known as Vitex diversifolia. 7 Information from J.C. Okafor. 8

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LOST CROPS OF AFRICA 240 Vitex payos (Lour.) Merr. These fruits, the “real” chocolate berries, are very popular in parts of southern and eastern Africa, from roughly Mozambique to Tanzania. Zimbabwean villagers are said to collect them in quantity every winter.9 Each fruit is about 2 cm long, with pointed tips and a chocolate brown or black skin. The juicy pulp surrounds a single hard stone. However, it is definitely an acquired taste. Westerners are typically offended by the flavor, the powdery texture, the oily mouthfeel, and the strong smell. But even then not all is lost: Since 1990, Zimbabwean entrepreneurs have been making jam from the fruit and selling it in the city markets. The low-growing tree is attractive enough to have promise purely as an ornamental. In full flower it becomes bespangled with myriad flowers, which, set off against the gray of the wood, attract both attention and praise. This is another Vitex that has received some horticultural exploration.10 Its woody seed has proven reluctant to germinate, but one method for overcoming this natural resistance is leaving seeds out in the open for a year then knick the end where there are two holes. Trees grow slowly during the first three years in the nursery, but then growth speeds up.11 Vitex madiensis Oliv. This similar but smaller tree (5-10 m high) occurs from Senegal to Uganda and from Uganda to South Africa. Nowhere, however, is it common. Indeed, everywhere it is rather rare. Most specimens are found in open woodlands. In season, black, egg-shaped fruits dangle from the branches on long stalks. Their smooth and transparent skins enclose a black pulp that is exceptionally popular among all those who know it. The fruits are commonly harvested and sold by women in local and regional market, as are the leaves and roots, which are used in medicine. Because of the social and economic importance of Vitex madiensis, it is considered a top species for local agroforestry. Recent horticultural research to understand the species and identify, select, and reproduce elite types for local growers is showing good results, especially documenting reliable vegetative propagation techniques such as rooting and air-layering.12 Similar “domestication” research on other Vitex species, indeed on “lost” African fruits in general, could quickly advance them from obscurity, and could be accomplished with little expense by horticultural workers across Africa. “Around Bulawayo you get Vitex isotjensis, Vitex mombassae and Vitex payos,” writes 9 our contributor Ray Perry. “The last is the best. It is sold in the markets and is among the most popular indigenous fruits.” Information from Ray Perry, who adds that care must be taken because the seedlings 10 are easily over-watered. Information from Ray Perry. 11 Mapongmetsem, P.M. 2006. Domestication of Vitex madiensis in the Adamawa 12 Highlands of Cameroon: phenology and propagation. Akdeniz Üniversitesi Ziraat Fakültesi Dergisi 19(2):269-278.

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CHOCOLATE BERRIES 241 Vitex mombassae Vatke In East and southern Africa, the ripe fruits of this species are picked by the wayside, eaten in homes, and even sold in markets. They are borne in profusion and are eagerly sought. It has been said that Pedi women willingly donate a day’s work for permission to gather mphu from a farmer’s property. The fruits are eaten fresh but are also boiled up into a sweet, black concoction used at least in part for strengthening and flavoring tobacco. Vitex pooara Corbishley Another southern African species (or perhaps the same as V. mombassae), this tree is typically 4-5 m. tall with small, violet- hued flowers. The fruits are 2 cm long, very dark purple or black when ripe, and the calyx may enclose half the fruit. In South Africa’s Waterberg region the fruits become so plentiful in season they constitute an important part of the Pedi diet. One drawback is that the juice may stain the mouth; after eating these chocolate berries everyone has black lips.