The Red Queen and the Hard Reds: Productivity Growth in American Wheat, 1800-1940

The standard treatment of U.S. agriculture asserts that, before the 1930s, productivity growth was almost exclusively the result of mechanization rather than biological innovations. This paper shows that, to the contrary, U.S. wheat production witnessed a biological revolution during the 19th and early 20th centuries with wholesale changes in the varieties grown and cultural practices employed. Without these changes, vast expanses of the wheat belt could not have sustained commercial production and yields everywhere would have plummeted due to the increasing severity of insects, diseases, and weeds. Our revised estimates of Parker and Klein's productivity calculations indicate that biological innovations account for roughly one-half of labor productivity growth between 1839 and 1909.