In 1986 approximately 83 percent of the active population were farmers or herders. This sector of the economy accounted for almost half of GDP. With the exception of cotton, some small-scale sugar production, and a portion of the peanut crop, Chad's agriculture consisted of subsistence food production. The types of crops that were grown and the locations of herds were determined by considerable variations in Chad's climate.
The soudanian zone comprises those areas with an average annual rainfall of 800 millimeters or more. This region, which accounts for about 10 percent of the total land area, contains the nation's most fertile croplands. Settled agricultural communities growing a wide variety of food crops are its main features. Fishing is important in the rivers, and families raise goats, chickens, and, in some cases, oxen for plowing. In 1983 about 72 percent of all land under cultivation in Chad was in the soudanian region.
The central zone, the sahelian region, comprises the area with average annual rainfall of between 350 and 800 millimeters. The minimum rainfall needed for the hardiest of Chad's varieties of millet, called berebere, is 350 millimeters. The western area of the zone is dominated by the Chari and Logone rivers, which flow north from their sources in southern Chad and neighboring countries. The courses of these rivers, joining at N'Djamena to flow on to Lake Chad, create an ecological subregion. Fishing is important for the peoples along the rivers and along the shores of Lake Chad. Flood recession cropping is practiced along the edges of the riverbeds and lakeshore, areas that have held the most promise for irrigation in the zone. International donor attention focused on this potential beginning in the mid-1960s. Particular attention has been paid to the traditional construction of polders along the shores of Lake Chad. Land reclaimed by the use of such methods is extremely fertile. Chad's only wheat crop is cultivated in these polders.
In the rest of the sahelian region, the hardier varieties of millet, along with peanuts and dry beans, are grown. Crop yields are far lower than they are in the south or near rivers and lakes. Farmers take every advantage of seasonal flooding to grow recession crops before the waters dry away, a practice particularly popular around Lake Fitri. The sahelian region is ideal for pasturage. Herding includes large cattle herds for commercial sale, and goats, sheep, donkeys, and some horses are common in all villages.
The Saharan zone encompasses roughly the northern one-third of Chad. Except for some dates and legumes grown in the scattered oases, the area is not productive. Annual rainfall averages less than 350 millimeters, and the land is sparsely populated by nomadic tribes. Many of Chad's camel herds are found in the region, but there are few cattle or horses.
Chad's subsistence farmers practice traditional slash-and-burn agriculture in tandem with crop rotation, which is typical throughout much of Africa. Sorghum is the most important food crop, followed by millet and berebere. Less prevalent grains are corn, rice, and wheat. Other secondary crops include peanuts, sesame, legumes, and tubers, as well as a variety of garden vegetables.
Crop rotation in the soudanian zone traditionally begins with sorghum or millet in the first year. Mixed crops of sorghum and/or millet, with peanuts, legumes, or tubers, are then cultivated for approximately three years. Farmers then return the land to fallow for periods up to fifteen years, turning to different fields for the next cycle. Preparation of a field begins with cutting heavy brush and unwanted low trees or branches that are then laid on the ground. Collectively owned lands are parceled out during the dry season, and the fields are burned just before the onset of the first rains, usually around March. Farmers work most intensively during the rains between May and October, planting, weeding and protecting the crops from birds and animals. Harvesting begins in September and October with the early varieties of sorghum. The main harvest occurs in November and December. Farmers harvest crops of rice and berebere, grown along receding water courses, as late as February.
The cropping cycle for most of the sahelian zone is similar, although the variety of crops planted is more limited because of dryness. In the polders of Lake Chad, farmers grow a wide range of crops; two harvests per year for corn, sorghum, and legumes are possible from February or March to September. Rice ripens in February, and wheat ripens in May.
As with most Third World countries, control of the land determines agricultural practices. There are three basic types of land tenure in Chad. The first is collective ownership by villages of croplands in their environs. In principle, such lands belong to a village collectively under the management of the village chief or the traditional chef des terres (chief of the lands). Individual farmers hold inalienable and transmittable use rights to village lands, so long as they, their heirs, or recognized representatives cultivate the land. Outsiders can farm village lands only with the authorization of the village chief or chef des terres. Renting village farmlands is possible in some local areas but is not traditional practice. Private ownership is the second type of tenure, applied traditionally to the small plots cultivated in wadis or oases. Wells belong to individuals or groups with rights to the land. Ownership of fruit trees and date palms in the oases is often separate from ownership of the land; those farmers who plant and care for trees own them. State ownership is the third type, primarily for large enterprises such as irrigation projects. Under the management of parastatal or government employees, farmers enter into contractual arrangements, including paying fees, for the use of state lands and the benefits of improved farming methods.
Detailed and reliable statistical information on Chad's agriculture was scarce in the late 1980s; most researchers viewed available statistics only as indicators of general trends. The one region for which figures were kept was the soudanian zone through survey coverage by officials of the National Office of Rural Development (Office National de Développement Rural--ONDR), who monitored cotton production. These officials also gathered information on food production, but this effort was not carried out systematically. Survey coverage of the sahelian zone was first hampered, then prevented, by civil conflict from the mid1970s to the early 1980s.
Moreover, figures from international and regional organizations often conflicted or differed in formulation. For example, total area devoted to food production was difficult to estimate because sources combined the area of fields in production with those lying fallow to give a total for arable lands. The arable land figure has shown a gradual increase since 1961. Estimated then at 2.9 million hectares, it rose to almost 3.2 million hectares in 1984. In 1983 there were about 1.2 million hectares in food production and in 1984 slightly more than 900,000 hectares. Therefore, perhaps a third of Chad's farmlands were in production in a given year, with the balance lying fallow.