Growing corn for ethanol may lead to increased CO2 emissions from clearing land

Spurred in part by federal subsidies and mandates for corn ethanol, farmers have looked for ways to grow more corn in order to turn a bigger profit. One way is to alter the practice of crop rotation, which is meant to keep soil nutrients intact. Another is to clear and cultivate new fields to increase corn acreage, sometimes taking land out of the Conservation Reserve Program.  (For example, in Iowa, farmers withdrew early about 24,000 acres of Conservation Reserve Program land in 2008.[[The USDA's Farm Services Administration administers all aspects of the Conservation Reserve Program (CRP). They report data monthly and yearly on CRP enrollment.]])  Farming new land can release carbon dioxide that had been trapped in soil, allowing it to enter the atmosphere. And some researchers suggest that switching corn production in the US to supply fuel instead of food might lead to land clearing to grow food crops in other parts of the world, which can further increase the amount of CO2 entering the atmosphere.