US Maize Yield Growth Implications for Ethanol and Greenhouse Gas Emissions

Abstract

During the past half century, per-acre maize yields have increased due to improved cultivars, better management, and favorable weather. Recent US biofuel legislation, e.g., revised Renewable Fuel Standard, has increased the demand for biofuel and added competition for available cropland. Growth in maize yield may alleviate the potential impacts, including greenhouse gas effects, of rising food, feed, and fuel demand. Using 1960-2009 maize yields for the United States and top maizeproducing states, we test for structural breaks and develop yield trend and growth forecasts for 2030. Depending on the forecasting model, US maize yield ranges from 205 to 242 bushels per acre in 2030. Holding maize production constant at the 2009 level, 16-25 million acres could be shifted to other crop production. Maize yield forecasts are sensitive to model choice (linear trend vs. growth rate) and time period (short- vs. long-run trends). Ultimately, maize yield growth and trends have important impacts on greenhouse gas emissions. © 2011 AgBioForum.