DNR Liquid Manure Rules

Starting Feb. 1, animal producers with totally roofed (confinement) facilities face limits on land applying liquid manure if the ground is frozen.  

The state rules kick in then, because runoff and nutrient loss after winter manure application is more likely when manure can’t be injected into the soil or incorporated into a field.

Dating back to Dec. 21, manure application is also limited on snow-covered ground. These limits affect confinement facilities with liquid manure that have 500 or more animal units. Generally, 500 animal units equals 1,250 finishing hogs; 5,000 nursery pigs; 500 steers, immature dairy cows or other cattle; or 357 mature dairy cows.

Except in emergencies, the law limits liquid manure application from Dec. 21 to April 1 if the ground is snow-covered with an inch or more of snow or one-half inch of ice. Liquid manure application on frozen ground, soil that is impenetrable due to frozen soil moisture, is restricted from Feb. 1 to April 1. However, frozen ground does not include soil frozen two inches deep or less. If manure can be properly injected or incorporated, it can be land applied during this time. Producers must call the local DNR field office to report emergency applications before they apply.

While the law affects confinements with liquid manure, open feedlots and poultry producers can help keep manure in place by using common sense and choosing application areas far from a stream, on flat land with little snow cover.

All producers must follow setbacks from certain buildings and environmentally sensitive areas.