Composting is a treatment option that can reduce the volume of spent litter, change the nutrient composition, pasteurise weed seeds and pathogens, and reduce odour generation compared with raw litter and anaerobic stockpiles. Composting is the managed breakdown of an organic material using aerobic bacteria. The aerobic bacteria used in composting require a constant source of oxygen and produce heat throughout the decomposition process, and therefore regular conditioning of the compost is required. Along with oxygen, the nutrient composition (particularly the carbon:nitrogen ratio) and moisture content of the compost also affect the performance of the composting process and must be carefully managed.

The Australian Standard AS 4454-2012: Composts, soil conditioners and mulches (Australian Standards, 2012) details the physical, chemical, biological and labelling requirements for materials that are specified as a “compost”. One of the primary objectives of the standard is to facilitate the beneficial recycling and use of compostable organic materials with minimal adverse impact on environmental and public health. It details best practice guidelines on composting materials, including desired temperature, turning and testing requirements.

For more information about composting see the Poultry waste composting guidelines developed by Rod Jenner et al. (2020).