Essential practices for safe in-field manure stacking

Thursday, December 12, 2024

In-field manure stacking involves temporarily storing solid manure in a crop field, typically in a windrow or cone-shaped pile on an unimproved surface.

This practice can be useful in various situations, such as when importing manure or waiting for optimal land application conditions, like avoiding winter applications.

Manure stacked in a field must be applied to land by the next growing season or within 120 days of stacking, whichever comes first.

However, if manure is intended to be stacked longer, covering the pile with an impermeable cover within three weeks can extend the stacking period.

Covering the manure has several benefits, including reducing odor, preventing nutrient leaching, improving handling for future application, and controlling fly larvae.

In Pennsylvania, certain guidelines must be followed for in-field manure stacking, which applies to both manure produced on-site and manure imported to the operation.

These guidelines exclude stacking on improved or impermeable surfaces, composting, and emergency stacking situations.

The following practices are required for compliance:

Indicate stacking locations on your Act 38 Nutrient Management or Manure Management Plan and rotate them so no stack occupies the same area for more than four years.
Shape stacks into a cone or windrow to shed rainwater, unless covered with an impermeable cover.
Stack manure at least 100 feet from surface water, sinkholes, and wells.
Avoid stacking in areas with excessive drainage or near subsurface drains unless covered within three weeks.
Do not stack on slopes greater than 8%, or near the bottom of a slope with over 100 feet of runoff.
Use diversions for stacks located more than 100 feet from the top of a 3-8% slope.
Ensure the stack is at least 4 feet high and dry enough to hold its shape.
Only stack the amount of manure needed for nearby fields.

By following these guidelines, the environmental impact of in-field manure stacking can be minimized, providing valuable flexibility while maintaining proper nutrient management. For more information, visit the Nutrient Management Education Program website.