Weather and Technology in the Production of Corn in the U. S. Corn Belt
1969
Thompson, Louis M.
The influence of weather was separated from the influence of technology on the yield of corn by the use of time trends for technology and multiple curvilinear regression for weather variables in five Corn Belt states. A time trend from 1930 to 1960 indicated an average annual increase of 51 kg of grain per ha. A time trend from 1960 to 1967 indicated an average annual increase of 201 kg of grain per ha. Weather variables accounted for most of the variation from the tune trends. Average June temperature appeared optimum for corn while below-average temperatures in July and August were associated with highest yields. Average precipitation from September through June appeared optimum for corn, but highest yields were associated with above-average rainfall in July. The influence of August rainfall was not significant.
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