DES MOINES -- Dry conditions and warm weather provided an early harvest and manure application season. However, here are a few reminders if winter application is still necessary.

Confinements with liquid manure--restrictions start Dec. 21

Runoff into streams is more likely to occur during winter manure application due to frozen ground. State law limits liquid manure application for confinement operations (roofed facilities) with more than 500 animal units. Restrictions on applying manure to snow-covered ground begin December 21 and continue until April 1, 2026. Liquid manure cannot be applied to fields covered with 1 inch or more of snow or 0.5 inches of ice, except in an emergency.

Starting Feb. 1, applying liquid manure on frozen ground is also restricted until April 1. Call your local DNR field office prior to any emergency application..

Other limits may apply if you took credit for injection or incorporation as part of a construction permit application using the Master Matrix.

Winter land application of liquid manure from confinements is allowed when producers can inject or incorporate manure on the same date, and when the ground is not frozen or snow-covered.

Rules for all producers

While limits on winter land application do not apply to open feedlots, dry manure and small confinement producers, all producers must prevent water quality violations. Often they can help protect water quality by using common sense, and choosing application areas far from a stream on flat land with little snow cover.

All surface land application must follow setbacks from buildings and environmentally sensitive areas. Look for more information on winter application rules on DNR’s animal feeding operations web page.

These three tips can help prevent spills and fish kills, and they’ll also help keep applicators safe.

  1. SLOW DOWN! Getting in a hurry has caused past spills and accidents. Don’t try to speed things up and then accidentally miss the corner and land in the ditch.
  2. Be diligent. Pay attention during pumping and land application, watching the equipment, weather and land. Stay away from saturated soils and be aware of the potential for runoff. Don’t over apply. Walk or ride the umbilical line before and during pumping to ensure all of the couplings are and remain fastened. Don’t leave running equipment unattended.
  3. Avoid water. Keep umbilical hoses and application equipment away from bridges, creeks and tile intakes. Avoid surface application by injecting or incorporating. Stay away from sensitive areas and steep slopes. Follow required separation distances for your operation.

Reported manure releases are down compared to last year, but if an event happens, call in a spill report as soon as you can to 515-725-8694. DNR staff are experienced in handling spills. They can likely help you keep a bad situation from becoming worse.

Following best management practices for the application of manure can help reduce the potential for nutrients to enter Iowa’s water resources.