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| On left, typical maize crop before FGW. On right, after implementation of FGW. |
By Don Lotter, Ph.D., consultant to MCC Sand Dam Program 2011.
Africa has fallen behind the rest of the world in food production, and is the only continent whose per capita food production has decreased in the past 50 years rather than increased. Attempts to rectify this situation have been many, but apparently none of the strategies have worked. A crop production system that is adapted to the African farmer, and that the African farmer responds to, is needed.
Part of a sand dam program is to work with the agriculture that covers the watershed of each dam. Soil erosion from crop land can clog a sand dam aquifer with silt and clay.
Recently MCC sponsored a workshop on a food production method that just may be what farmers here need. It is known as "Farming God's Way" (FGW). FGW is firmly and unabashedly rooted in the Christian Bible, and African farmers clearly resonate with this - even non-Christians, such as the Muslim farmer who attended the MCC workshop (he was the best asker of questions and was enthusiastically engaged).
As an agricultural scientist, I can testify that the FGW practices agronomically sound. FGW is similar in practice to what is known as "Conservation Agriculture", a system that has developed around southern Africa in the past decade, especially Zambia and Zimbabwe. Both systems use a technique of digging small basins, about 15,000 per hectare in semi-arid areas like Dodoma, for placing fertilizer and seed, and both do not till the surrounding soil. Both encourage a mulch cover. For FGW the mulch, known as "God's Blanket", is essential.
Africa's, and much of the world's, cropland soil is washing away at a rate of many dozens of tons of soil per hectare per year due to tillage and poor husbandry. A mulch that covers 80% of the soil surface will reduce soil erosion by 90% on the average, according to the UN Food and Agiculture Organization. This not the only reason mulching is so central to FGW. The reason soil does not erode from mulched land is because water is soaking in, not running off into streams and rivers. This soil water is then available to the crop later.
Soils in much of Africa are geologically old, unlike soils in Europe and North America that have been subject to glaciation. These African soils have been transformed by weathering such that they entail fundamentally different management, as they neither have nor hold nutrients well. Many of these soils are red from iron oxides. Organic matter, such as a mulch, is much more important in these tropical soils than in North American and European soils, where synthetic fertilizers generally get a good response. Despite decades of agricultural work in Africa, Western and Western-trained African agricultural scientists and development workers have been very slow to recognize the importance of organic matter to soil fertility here.
Soils in much of Africa are geologically old, unlike soils in Europe and North America that have been subject to glaciation. These African soils have been transformed by weathering such that they entail fundamentally different management, as they neither have nor hold nutrients well. Many of these soils are red from iron oxides. Organic matter, such as a mulch, is much more important in these tropical soils than in North American and European soils, where synthetic fertilizers generally get a good response. Despite decades of agricultural work in Africa, Western and Western-trained African agricultural scientists and development workers have been very slow to recognize the importance of organic matter to soil fertility here.
A mulch cover simulates the leafy ground cover in a forest. One of the enduring agronomic problems in the tropics is the locking up of phosphorus by certain tropical soils (especially the red-colored soils). Tropical forest trees get around this by having their roots tap into the decomposing mulch that is a natural part of forests. Phosphorus becomes available to the plant as it is released from the decomposing mulch into the rich organic layer on top of the soil, before it gets into the soil and gets tied up. Mulches can free up phosphorus in this way.
Each small basin gets a handful of fertilzer - either composted manure or synthetic fertilizer. Often wood ash or ant hill soil is added. A layer of soil is put on top of this before placing seed. For maize, beans and other large-seeded crops, three seeds are placed and in the case of maize covered with 5 cm of soil. Two weeks later, when the plants have popped through the mulch "blanket", each set of three basins will be thinned to a total of six plants (if one basin has one plant, the next one is left with three).
After planting the seeds, the mulch "Blanket" is laid down, up to six inches deep if enough material is available. In some regions where confined livestock husbandry is common, such as around Arusha, farmers will have diffiulties obtaining sufficient mulch material, as nearly all crop residues are used for fodder. In these areas it is all the more critical to teach to importance of mulch so that farmers make the investment. Weeding is mandatory after seven to ten days so as to get into the habit of keeping weeds down.
Legume green manure crops are generally planted at the end of the maize cycle, depending on the area, or a legume crop is rotated in place of maize.
According to FGW trainer Grant Dryden of Port Elizabeth, South Africa (Grant is pictured in the FGW slideshow to right), yields of maize commonly increased ten-fold within two years.
