Different livestock feeding practices generate varying levels of greenhouse gas (GHG) emissions, specifically carbon dioxide (CO2) and nitrous oxide (N2O) emissions. There are limitations and benefits associated with each feeding practice. Cows and other ruminants account for about four percent of all GHG emissions produced in the United States, and proper animal grazing management systems can help mitigate these emissions.
- Baling hay involves a series of steps that generate greenhouse gas (GHG) emissions from the fuel consumption of mowing, conditioning, raking, baling, transporting and storage operations. Baling practices that allow higher hay moisture can help decrease the miles spent on the field.
- Cover crops have beneficial effects on soil health, C sequestration, and environmental quality parameters, but may also increase CO2 emissions compared to no cover crops and have a variable effect on N2O emissions.
- When agricultural production and feeding management practices are combined, livestock can contribute to the reduction of carbon emissions, while helping enhance soil fertility.
- Cover crops can provide winter forage for livestock, replacing purchased or stored winter feed and can result in an average $40/acre/year in net benefit. When long-term cover crop benefits are included in the calculations the average net benefit is $135/acre/year.
- GHG emissions of the different feeding practices vary based on the cover crop species, the quality and quantity of biomass residue and how the residue is placed in the soil, but grazed and ungrazed cover crops tend to show no difference in GHG emissions.
- The effects of baling hay and grazing vs. non-grazing cover crops on GHG emissions are unclear.
- Although cover crops can enhance soil health and environmental quality through increased carbon and nitrogen cycling, their exact effects on GHG emissions still remain unknown.
- Because of the diversity of factors that influence emissions of CO2 and N2O, it is difficult to identify practices that deliver overall mitigation of GHG emissions.