The Science Daily website reports a comparative study by Iowa State University (United States) on the single and double cropping of sorghum for biofuel production. They designed experiments on 12 varieties of sorghum grown in single and double cropping systems, and assessed the yields for biofuel production. The study is published in the Agronomy Journal (URL above). The study showed that a single-cropping system was more effective for the production of ethanol. According to researcher and senior author, Ben Goffe, growing sorghum as a sole crop is more efficient for ethanol production, from a production point of view. However, "it remains to be seen whether the favorable long-term environmental benefits, such as reduced erosion potential, of the double-cropping systems merits the reduced total biomass production". Goffe recommends further studies on the double cropping systems, focusing on strategies to maximize sorghum production, such as incorporating a winter crop that matures earlier in the season.