Greenhouse Gas Calculator (1 of 2) (IMAGE) American Society of Agronomy Caption Whether tilled or untilled, corn years always had the largest greenhouse gas losses due to large fertilizer additions. Credit Claire P. McSwiney Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.