Evans School Policy Analysis & Research Group (EPAR)

There is a wide gap between realized and potential yields for many crops in Sub-Saharan Africa (SSA). Experts identify poor soil quality as a primary constraint to increased agricultural productivity. Therefore, increasing agricultural productivity by improving soil quality is seen as a viable strategy to enhance food security. Yet adoption rates of programs focused on improving soil quality have generally been lower than expected. We explore a seldom considered factor that may limit farmers’ demand for improved soil quality, namely, whether farmers’ self-assessments of their soil quality match soil scientists’ assessments. In this paper, using Tanzania National Panel Survey (TZNPS) data, part of the Living Standards Measurement Study – Integrated Surveys on Agriculture (LSMS-ISA), we compare farmers’ own assessments of soil quality with scientific measurements of soil quality from the Harmonized World Soil Database (HWSD). We find a considerable “mismatch” and most notably, that 11.5 percent of survey households that reported having “good” soil quality are measured by scientific standards to have severely constrained nutrient availability. Mismatches between scientific measurements and farmer assessments of soil quality may highlight a potential barrier for programs seeking to encourage farmers to adopt soil quality improvement activities. 

Nigeria’s experience with fertilizer subsidy programs has been different than that of other countries in Sub-Saharan Africa. Nigeria is one of the only African countries capable of producing fertilizer domestically. But Nigeria is also large and densely populated. This makes national agricultural policy difficult due to logistical problems with implementation and the unique fertilizer needs of the various agro-ecological zones. This research brief discusses the effects of Nigeria’s input subsidy programs on maize production and fertilizer consumption. It focuses on the years 2000 to 2007, but also includes a discussion of Nigeria’s subsidy history from the early 1970s to 2009. Researchers have had difficulty studying Nigeria’s subsidy schemes due to a lack of data. In spite of decades of authoritarian, centralized leadership, Nigeria’s states have significant power to implement their own subsidies. This complicates any evaluation of a program’s effectiveness, in part due to the variety of subsidies at any given time, as well as inconsistent accounting practices.