![Sample our Global Development journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5929/TOC-Subject-Sample-2021-Global-Development.jpg"})
ABSTRACT
Soil fertility management (SFM) practices such as maize-legume intercropping and organic fertiliser, particularly when used jointly with inorganic fertiliser, have the potential to increase yields and yield response to inorganic fertiliser, improve soil health, and contribute to sustainable intensification (SI). However, relatively little is known about the drivers of adoption of these practices, especially for joint use. Moreover, it has been suggested that African farmers will respond to an increase in the maize price they expect to receive at the next harvest by increasing investment in their soils or altering use of SFM practices in response to input price changes. Yet previous studies largely ignore the role of prices. Using nationwide household panel survey data from Kenya, we estimate the effects of changes in crop and input prices on household use of individual SFM practices and combinations thereof. We find that Kenyan smallholders’ SFM adoption decisions are largely insensitive to changes in expected maize prices. However, when inorganic fertiliser prices rise, farmers are more likely to use organic fertiliser and use less inorganic fertiliser per acre. These results suggest that price policies alone are unlikely to be effective ways to promote SI of maize production in Kenya.
Acknowledgements
The authors gratefully acknowledge funding support from the United States Agency for International Development (USAID) Kenya Mission through the Tegemeo Agricultural Policy Research and Analysis II (TAPRA II) Project [grant number is RC101-650]. Additional funding support was provided by the U.S. Department of Agriculture (USDA) National Institute of Food and Agriculture and Michigan AgBioResearch [project number MICL02501]. The contents are the sole responsibility of the authors and do not necessarily reflect the views of USAID, USDA, the United States Government, Michigan AgBioResearch, or Michigan State University. The authors also wish to thank Bob Myers and Robby Richardson for feedback on an earlier version of the paper, and John Olwande for providing helpful information on lean season purchase prices. This paper is a revised version of a conference paper (Olson et al. Citation2017) and Olson's master's thesis (Olson Citation2018).
Disclosure statement
No potential conflict of interest was reported by the author(s).
Notes
1 Similar definitions have been used by Snapp et al. (2017) and others. Snapp et al. (2017) also integrate social and human condition dimensions into their definition of SI.
2 Farmers do not know what maize prices will be at harvest time when they are making SFM adoption decisions, so it is their expectation of the maize price that is likely to affect behavior.
3 We do not analyze other SFM practices such as maize-legume rotations due to data constraints.
4 See Kim et al. (Citation2019) for a detailed discussion of the rationale for the different SI category designations.
5 The two most commonly used inorganic fertilisers in our data are diammonium phosphate (DAP) and calcium ammonium nitrate (CAN). DAP is applied to 69.9% of maize plots, while CAN is applied to 32.3%; 38.4% of maize plots have both applied. DAP is commonly used as basal dressing and CAN as top dressing in Kenya, which is why there is significant overlap in their application.
6 Note that in Procedure 17.3, Tobit (regular) residuals are used, whereas in a control function approach, the Tobit generalised residuals would be used (Wooldridge Citation2010).
7 We thank an anonymous reviewer for recommending we underscore these important points.