On-farm composting of flood spoilage

Using spoiled forages

Floods can damage hay, silage and grain. Always check flood-affected feed before giving it to livestock. If it is unsafe, you can still reuse it in other ways:

• Give away or sell it as mulch. Gardeners and small crop growers often prefer grassy mulch, such as tropical grass hay.
• Use it in livestock holding areas or laneways to absorb urine and manure. Remove the material later for aerobic composting.
• Compost it on your property to recycle nutrients and improve soil carbon.
• Use it in composting systems for animal carcases.

Benefits of composting on-farm

Composting can:

• turn waste into a useful product
• improve soil health and structure
• reduce the need for chemical fertilisers
• help manage organic waste safely

On-farm composting must be done with care to avoid environmental harm. In New South Wales, large composting facilities need a licence and must follow Environmental Protection Authority (EPA) rules. See the guidelines for Composting and Organics Processing Facilities.

Small-scale or home composting usually does not need a licence. However, you must still take steps to minimise odours, leachate and run-off.

Choosing a composting site

Select a site that:

• has low-permeability soil or a hard base such as concrete or clay
• is at least 2 metres above the water table
• is flat or gently sloped (less than 5%)
• is accessible to tractors or machinery
• is located above flood levels and away from waterways
• is well away from neighbours and public spaces
• is hidden from public view, especially when composting animal carcases.

Composting spoiled feed and manure

For large volumes of spoiled feed, windrow composting is often the easiest and most cost-effective method. It uses fungi and bacteria to break down organic matter in the presence of oxygen.

Silage spoilage often starts when oxygen enters the bale. White fungal growth may indicate composting has already begun. To complete the process:

• Remove and dispose of plastic wrap, netting and twine.
• Add woody materials and manures to balance the mix.
• Turn the pile regularly and keep it moist.

You can:

• use a front-end loader or windrow turner for large piles
• build a three-sided bin for smaller areas, making it easier to turn the pile.

Learn more about this method of composting.

Composting livestock mortalities

If you cannot access knackery or rendering services, composting is a safe way to manage livestock deaths. First, contact a vet if the cause of death is unknown or if symptoms may indicate Emergency Animal Disease. Diseased animal remains may not be suitable for disposal by composting.

To set up a mortality compost pile:

• start with a thick base of carbon-rich material like sawdust or woodchips
• place the carcass on top
• cover it with spoiled, wet hay or silage
• use about 10 to 12 cubic metres of material for each adult cattle carcass.

Because this compost contains restricted animal material (RAM):

• fence off the site to keep out livestock and wildlife
• let the pile sit undisturbed for 4 to 6 months.

After this period, you can turn the compost and manage it like other piles. Remove any large bones before spreading. You can compost them again in a new pile.

Wait at least 28 days before grazing livestock on areas treated with RAM compost. This helps reduce disease risks like botulism and ensures pasture has regrown through the compost.

For other disposal options, see the guide on animal disposal after a disaster.

More information

Heavy rainfall can affect waterways, stormwater and wastewater systems. For more information, see the NSW EPA guidance on stormwater management.