By Douglas Beegle, Extension Agronomist

Winter manure application is probably the most sensitive nutrient management issue that farmers face. Many outside of agriculture feel that it should be completely banned. We all know that winter is not the best time to apply manure and should be our last choice. 

But the reality is that on many of our farms there are no other practical options. Also, unfortunately, sometimes we do not plan adequately for the storage getting full before the conditions are fit for manure applications, which forces us to do some spreading when we probably shouldn’t. 

If late fall, winter, or early spring manure applications are necessary, we really need to bend over backwards to do the best possible job of applying this manure if we want to continue to have this as an option. This means making an extra effort to try to select the best fields and timing of application to minimize the potential for loss, and thus maximize the nutrients that will be available for crop uptake. 

Also, we need to be aware of public perception and think about how people might view a winter application on a given field. This is largely common sense, but there are regulations that apply to all manure application in Pennsylvania.

1. Select fields with cover crops or at least good residue.
   • Regulations require a cover crop or at least 25% residue for winter spreading.
2. Stay as far away from water as practical.
   • Regulations require staying 100 feet from water in the winter.
3. Select the most level fields available and especially avoid significant slopes.
   • Regulations prohibit manure application on slopes greater than 15%.
4. Avoid spreading high rates of manure in the winter.
   • Regulations limit winter manure applications to the following, unless you have an approved nutrient management plan.
     • No more than 5,000 gallons per acre of liquid manure
     • No more than 20 tons per acre of dry non-poultry manure
     • No more than 3 tons per acre of poultry manure
5. Avoid areas in fields where concentrated water flow is likely.
6. Avoid poorly drained fields.
7. Don’t spread on snow unless it’s unavoidable. Try to avoid spreading when rain or melting conditions are expected.
8. Stay away from roads and don't spread in road ditches.
9. For daily spreading, mark where you stop spreading in case fresh snow covers up the previous application to avoid skips and overlaps.

Note that from a regulatory point of view, winter is defined as:

• Dec. 15 through Feb. 28, or
• Anytime the ground is frozen at least 4 inches, or
• Anytime the ground is snow covered

While the regulations listed above are specific to winter, these management guidelines are still very applicable to early spring conditions that might not meet the legal definition of winter.

All farms that apply manure in Pennsylvania must have a manure management plan. High density farms (CAOs) and farms with large numbers of animals (CAFOs) must have an approved Nutrient Management Plan. All other farms that apply manure must have a Manure Management Plan (MMP) based on the DEP Manure Management Manual. An MMP that meets these regulations includes special considerations for winter application of manure that are included in the list of management practices above.