Restrictions on applying manure to snow-covered ground starts Dec. 21. Runoff – into our waters – is more likely to occur during winter manure application. State law limits liquid manure application for confinement operations (roofed facilities with more than 500 animal units). They cannot apply liquid manure to fields covered with 1 inch of snow or 0.5 inches of ice, except in an emergency. Land application is OK if producers can properly inject or incorporate the manure. Starting Feb. 1, applying liquid manure on frozen ground is also restricted until April 1. Call the local DNR field office prior to any emergency application.
While not required of open feedlots and dry manure producers, all producers can help protect water quality by using common sense and choosing application areas far from a stream, and on flat land with little snow cover. All surface land application must follow setbacks from buildings and environmentally sensitive areas. Find more tips on winter manure application and the science behind it in Volume 3, Winter Application in the Iowa Manure Management Action Group’s Manure Management series.