The Top Two Benefits of Low Disturbance Manure Application
Before we know it, crops will soon be coming off the fields, giving producers a chance to spread some of the manure they’ve stored over the growing season. This nutrient packed organic matter has a long list of benefits that impact farm soils, however, it can also contribute to runoff nutrient losses and pose water quality risks if not managed correctly. According to Eric Young, a research soil scientist at the U.S. Dairy Forage Research Center, using a low disturbance manure application just might be the ticket to keeping soil nutrients where they belong.
“While conventional tillage incorporation of manure reduces ammonia loss, it disrupts soil structure and increases erosion potential compared to reduced- and no-tillage methods,” Young says. “Low disturbance manure application (LDMA) aims to achieve the nutrient conservation benefits of tillage incorporation while mitigating disturbance-induced erosion.”
Common LDMA methods include banding, banding with aeration, shallow disk-coulter injection, sweep injection, and various drag hose systems. LDMA can be used successfully in both annual cropping systems and perennial hay crop forages, Young notes.
Research has shown that LDMA conserves more nitrogen and decreases nutrient concentrations in runoff compared to surface and broadcast applications. This allows nutrients within the manure to be better absorbed within the soil.
Another benefit of LDMA is that it can also improve cover crop establishment for annual cropping systems. Cover crops planted during the cooler months need a strong establishment to come back strong after lying dormant during the winter.
“While no one LDMA method is best, several studies indicate shallow disk injection mitigates both particulate and dissolved nutrients in runoff more effectively than other methods,” Young says. “Additional research over multiple years and sites is required to better predict longer-term impacts LDMA on crop yield, soil quality, and runoff water quality risk.”
