Timing Manure Application Can Reduce Nitrous Oxide Emissions

Researchers at Penn State University explored how using dairy manure and legume cover crops in corn crop rotations can increase emissions of the potent greenhouse gas nitrous oxide. The increase was largely due to the typical timing of manure application, before planting the corn crop. This study found that farmers could reduce nitrous oxide emissions if they could apply manure after the crop is planted, closer to when the corn begins to take up nitrogen. In this study, better timing for nitrogen application allowed for a reduced total nitrogen application, including use of less inorganic nitrogen fertilizer.