Composting Livestock Manure

This guide gets into some of the technical details you need to understand when composting larger volumes of organic waste.

About These Guidelines


These guidelines apply generally to any composting effort, but are specifically adapted here to assist owners of horses in the management of horse manure/bedding material waste. Horse owners are fortunate in that horse manure is an ideal composting material. Horse manure has a C:N ratio that is almost perfectly balanced to the needs of the micro-organisms which perform composting action.

If you maintain the structure and moisture level of the compost pile in accordance with the guidelines given below, three things will be accomplished:
  • Naturally occurring chemical compounds in the manure will be rapidly stabilized and this will reduce the potential for them to escape into the environment with an adverse impact;
  • The manure and bedding material will produce a rich soil amendment; and,
  • The volume of the material will be reduced to about 1/3rd of its original mass.
An efficient compost process will stabilize the breakdown and loss of valuable nutrients in the manure. The stabilized nutrients can then be made available for future plant growth. Fresh manure tends to lose its' valuable nutrients into the air and water when the C:N ratio is out of balance or when the pile is exposed to uncontrolled amounts of rain water. Leaching nitrogen compounds can have a negative impact on nearby bodies of water and produce nuisance odors. Sound waste management is "Waste Reduction" at its best.

The information provided here is adapted from guidelines developed by the Northeast Regional Agricultural Engineering Service Cooperative Extension. This adaptation is a cooperative effort of Klickitat County Solid Waste and the Washington State Department of Ecology.