Assessing Tillage Systems for Reducing Ammonia Volatilization from Spring-Applied Slurry Manure

The effect of tillage management on NH ₃-N volatilization and its influence on succeeding corn (Zea mays L.) silage production were studied at the University of Massachusetts Agricultural Experiment Station (South Deerfield, MA) during 2010–2012 growing seasons. Tillage treatments consisted of disking before and after manure application, solid-tine aeration before and after manure application, and no-till management. The greatest NH ₃-N loss (61 percent) occurred within the first 8 h after slurry manure application regardless of tillage management. The greatest NH ₃-N emission occurred with surface application (no-till), which ranged between 5.2 and 10.3 kg NH ₃-N ha ⁻¹ (9–20 percent of NH ₃-N applied) over the 3 years of the study. Immediate incorporation of manure into soil through disking reduced NH ₃-N loss by 66 to 75 percent. Ammonia loss abatement with aeration before or after manure application ranged from 13 to 41 percent compared with surface manure application. Tillage management did not influence corn silage yield or quality.