Notice for those preparing manure management plans (MMPs): The county average yields now cover yields from 2016 to 2020. Find the updated yield data in Appendix A to the manure management plan (form 542-4000a) on the DNR’s AFO forms page.

Almost all MMP preparers use the county average yields to calculate manure application rates. Some preparers use their own yields, but must meet certain requirements to do so.

MMPs are required for confinement (totally roofed) feeding operations that land apply manure in Iowa and have an animal unit capacity of more than 500 animal units (1,250 finishing hogs or 500 beef or immature dairy cattle). MMPs are based on the nitrogen (or phosphorus) uptake needs of the planned crop.

Find out more on the Confinements webpage, including how to use the online eMMP option to file annual MMP updates.