1. Foundation for Advanced Studies on International Development Soil Fertility, Fertilizer, and the Maize Green Revolution in East Africa Tomoya Matsumoto and Takashi Yamano (FASID/GRIPS)

2. Foundation for Advanced Studies on International Development Introduction Maize and Fertilizer Use in Kenya and Uganda Data and Descriptive Analysis Data Dairy Production Systems and Organic Fertilizer Use Maize Costs, Income, and Profit Estimation Results Determinants of Fertilizer Use Determinants of Maize Yield Conclusions Contents

3. Foundation for Advanced Studies on International Development There is a growing interests in realizing an African Green Revolution. Kenya and Uganda provide an interesting contrast in maize production: Kenya high inputs, Uganda low inputs. In this study, we compare maize production in these countries to identify constraints on maize production Introduction

4. Foundation for Advanced Studies on International Development To describe fertilizer use and maize production, by calculating costs, income, and profit in Kenya and Uganda To Estimate the determinants of the maize yield, including soil fertility, inorganic and organic fertilizer applications. Is it profitable to use fertilizer? Purpose of This Study

5. Foundation for Advanced Studies on International Development Maize in Kenya and Uganda

6. Foundation for Advanced Studies on International Development Nitrogen Consumption in Kenya and Uganda

7. Foundation for Advanced Studies on International Development RePEAT Panel data Kenya: 2004 and 2007, 725 rural households Uganda: 2003 and 2005, 895 households Soil Sampling at the first survey Kenya about 77 percent Uganda about 67 percent Data

8. Foundation for Advanced Studies on International Development Survey Areas

9. Foundation for Advanced Studies on International Development AllPurchased HYV Maize Local/ Recycled Maize HYV Difference Number of Plots3,131 (100%) 1,848 (59.0%) 1,283 (41.0%) Maize Yield (kg/ha)1,9862,1721,718454* Inorganic Fertilizer Use (kg/ha) 94.7119.459.260.2** Organic Fertilizer Used (kg/ha) 1,9352,2581,471787** Carbon Content (%)2.482.592.330.26** Table 1. Summary Statistics in Kenya

10. Foundation for Advanced Studies on International Development AllPurchased HYV Maize Local/ Recycled Maize HYV Difference Number of Plots3,198 (100%) 680 (21.3%) 2,518 (78.7%) Maize Yield (kg/ha)1,5611,7191,518202 Inorganic Fertilizer Use (kg/ha) 2.49.10.68.5** Organic Fertilizer Used (kg/ha) 8614271 Carbon Content (%)2.352.152.40-0.25** Table 1. Summary Statistics in Uganda

11. Foundation for Advanced Studies on International Development Soil Nutrient Indicator N: soil nutrient indicator, E: soil condition, C: inorganic fertilizer, O: organic fertilizer Maize Yield Function L: plot size, S: seed quantity, A: TFP

12. Foundation for Advanced Studies on International Development We control for the household fixed effects to eliminate biases created by the correlation between the household fixed effects and independent variables. We apply the endogenous switching model to control for the maize seed type selection.

13. Foundation for Advanced Studies on International Development Main Hypotheses Does the soil fertility increase returns from external fertilizer applications? Is the inorganic fertilizer application optimal?

14. Foundation for Advanced Studies on International Development Maize Yield Fertilizer Application (DAP) Maize Price Fertilizer Price Uganda Kenya

15. Foundation for Advanced Studies on International Development

17. We do not find that the returns from external fertilizer depend on the soil fertility. This suggests that the external fertilizer applications would be useful even on poor soils in Uganda and Kenya. The soil carbon content has a large impact on the maize yield. The inorganic fertilizer use in Kenya is at about the optimal application rate. Main Findings

18. Foundation for Advanced Studies on International Development To increase the inorganic fertilizer use. We need to reduce the fertilizer–maize relative price. Because we find a large positive impact of the carbon content, the results suggest that it is important to improve the soil fertility. To do so, the organic fertilizer use has to increase. This is a new area for future research. Policy Implications

19. Foundation for Advanced Studies on International Development In Uganda Experiments in Jan-Feb 2009, providing a package of HYV seeds, fertilizer, and extension to households in randomly selected villages of RePEAT Samples Conduct a survey in 2010 to evaluate the impacts In Kenya Experiments in 2010 on crop insurance? Conduct a survey in 2011 What’s next for RePEAT Survey?