Benefits of low disturbance manure application

Authors: Young, Eric

Submitted to: Journal of Nutrient Management
Publication Type: Trade Journal
Publication Acceptance Date: 4/21/2020
Publication Date: 5/8/2020
Citation: Young, E.O. 2020. Benefits of low disturbance manure application. Journal of Nutrient Management. Summer 2020.

Interpretive Summary:

Technical Abstract: Manure is an important source of nutrients and organic matter for dairy farm soils when optimally managed, however it can contribute to runoff nutrient losses and pose water quality risks under certain conditions. Optimizing the timing, placement, and disturbance level of manure application has both economic and environmental implications. While conventional tillage incorporation of manure reduces ammonia loss, it disrupts soil structure and increase erosion potential compared to reduced- and no-tillage methods. 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. In both systems, research in the US and other countries show that LDMA conserves more nitrogen and decreases nutrient concentrations in runoff compare to surface/ broadcast. LDMA can also improve cover crop establishment for annual cropping systems. 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. 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.