Composted manure is animal manure that has been left to decompose and can be used as a nutrient-rich soil amendment for gardens. Composting manure has several benefits, including:

• Killing dangerous pathogens: During the composting process, microorganisms raise the temperature inside the compost pile, killing off things like bacteria, parasites, and viruses that might be present in the manure, making it safe to use.

• Neutralizing the odor of manure: Compost doesn’t have the same awful stench as manure, and the smell of compost is usually earthy.

• Reducing the volume of manure: Composting reduces the initial volume of organic waste by 30% to 50%, giving you a more manageable amount to work with while also freeing up storage space.

Composting manure is a process of piling together organic material so that microorganisms, like bacteria and fungi, can break it down to create a nutrient-rich soil amendment. Raw manure is high in nitrogen but doesn’t have enough carbon for the microorganisms, so it needs to be mixed with high-carbon items, also called “brown” items, like straw or sawdust. To become safe to use, manure must be heated above 145 F, which happens naturally because decaying organic matter generates heat.

While manures and composts are excellent soil amendments for the home gardener, gardeners should be aware of the potential environmental and health risks associated with using manures and manure-based composts. Animal manures harbor pathogens harmful to humans, including E. coli, Salmonella, and Campylobacter bacteria, and Giardia or Cryptosporidium protozoa. Regular soil testing can help gardeners avoid soil phosphorus buildup from continuously applying manures and composts to soils, and gardeners can follow some simple tips to reduce the health risks.