The contribution of herbicides and other technologies to corn production in the Corn Belt region, 1964 to 1979
1984
Schroder, D. | Headley, J.C. | Finley, R.M.
Extract: This report attempts to identify the contributions of herbicides, other technologies and weather to corn yields for the period 1964 to 1979 in the Corn Belt using three regression techniques. Technology variables included were acres treated with herbicides, genetic improvement, and fertilizer. Pooled cross-sectional time-series data were used to estimate partial regression coefficients and marginal products using a second degree polynomial function. The marginal value product of herbicides estimated at the mean of the sample was $4.20. In addition, changes in predicted yields were partitioned with respect to weather and technologies. Increased use of herbicides accounted for 20% of the increase in corn yields from 1964-79. Increased use of fertilizers, genetic improvement and weather differences accounted for 26, 13 and 42 percent of the yield increases respectively for the period 1964-79. There was no evidence that Corn Belt yields have reached a plateau.
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