Facing food insecurity in Africa: Why, after 30 years of work in organic agriculture, I am promoting the use of synthetic fertilizers and herbicides in small-scale staple crop production
2015
Lotter, Don
Food insecurity and the loss of soil nutrients and productive capacity in Africa are serious problems in light of the rapidly growing African population. In semi-arid central Tanzania currently practiced traditional crop production systems are no longer adaptive. Organic crop production methods alone, while having the capacity to enable food security, are not feasible for these small-scale farmers because of the extra land, skill, resources, and 5–7 years needed to benefit from them—particularly for maize. Maize, grown by 94 % of farmers, has substantial nitrogen needs. The most practical ways of satisfying maize nutrient needs is via integrated soil fertility management, a combination of organic and Green Revolution methods. Maize has been shown in research to outyield the indigenous crops millet and sorghum in nearly all situations including drought. Conservation Agriculture (CA) in Africa has two main categories—organic and herbicide-mediated. The organic version of CA, despite years of promotion, has had a low rate of adoption. Herbicide-mediated zero tillage CA via backpack sprayer can substantially increase conventional maize yields while at the same time nearly eliminating erosion and increasing rainwater capture up to fivefold. Glyphosate herbicide is a non-proprietary product produced in Africa and approved for small farm use. The systemic nature of glyphosate allows the killing of perennial grasses that would otherwise need deep plowing to kill. The rooted weed residues protect the soil from erosion. The risks of glyphosate use are substantially outweighed by the benefits of increased food security and crop system sustainability.
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