Burn piles can be risk to stock

13 April 2026

Farmers looking to ignite burn piles when fire restrictions are lifted are being urged to be cautious with stock.

Of particular concern are contaminants left in ash and debris from treated pine posts, which landholders may be burning after replacing fences damaged in recent fires.

Agriculture Victoria veterinary officer Dr Lydia Nicholson said a case near Wangaratta served as a sobering reminder of how well-intentioned actions can pose serious risks to livestock.

‘During a disease investigation, several cattle were found dead after displaying severe neurological signs – staggering, blindness and collapse,’ she said.

‘Post-mortem examinations and laboratory testing were conducted, but the key breakthrough came during a discussion with the landholder. It was revealed that a bonfire had recently been lit on the property and the burn pile included treated timber.’

Treated timber, which is commonly used in fencing, yards, and landscaping, is often preserved with copper chrome arsenate (CCA), a chemical that protects wood from rot and pests.

Dr Nicholson said CCA contains arsenic, which becomes significantly more toxic when the timber is burnt.

‘Burning concentrates the toxin and leaves behind ash and debris that can be highly palatable to livestock. In this case, every animal that had access to the burn site died,’ she said.

‘This tragic outcome highlights the importance of being vigilant about what goes into your burn piles. Even small pockets of contamination can lead to fatal consequences when stock gain access.’

Landholders should also be aware that many common garden plants can be toxic to livestock and access can be fatal, particularly on small properties where animals may reach household gardens or where clippings are dumped into paddocks or burn piles.

Dried clippings can pose an even greater risk, as they often become more palatable while retaining toxicity. Plants such as some sugar eucalypts, oleander, yew, foxglove and rhododendrons can cause severe illness or sudden death, often affecting the heart, nervous system or gastrointestinal tract.

Recently, a case was investigated where garden clippings containing oleander was placed on a burn pile, resulting in multiple deaths of horses on a property.

For further information contact your local veterinarian or Agriculture Victoria veterinary or animal health officer.

Further information can be found at Livestock and animals.

Media contact: media@deeca.vic.gov.au