The Value of Stabilizing Fertilizer under Carry-Over Conditions

This paper develops a dynamic programming model to examine the effects on yield and profitability of variability in spread of phosphate fertilizer under carry-over conditions and the value of technology which reduces this variability. The cost of uneven spread is high, if the plant-available soil phosphorus reserve is low. Therefore, the value of technology reducing variability in spread is high to farmers with less-developed land where soil phosphorus reserve is low. This value is also high to users of low carry-over fertilizers, i.e., nitrogen and potassium.