FIREFIGHTERS have warned conditions are ripe for haystack fires, as central Victoria's weather see-saws between wet, cool spells and hot days.
Farmers have been urged to make sure their hay bales are properly spaced, both for airflow and so internal temperature measurement is possible.
Country Fire Authority North West Region community engagement coordinator Paul Tangey urged farmers to remain vigilant when stacking hay.
Mr Tangey said it was vital farmers left gaps and tested the temperature of all bales.
He said hay, grass and wheat all had the potential to spontaneous combust when heated if any moisture was in the bale.
Mr Tangey said haystack fires could both destroy hundreds of bales of hay, and spark larger fires.
"Haystack fires do start a lot from self combustion, and when one ignites, you can lose the whole lot," he said.
"What we do ask people is when they're baling, make sure when they do it to a certain size, so they can stack them, and get in to test them."
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