Firefighters are battling to save a pine plantation after a large compost pile caught alight in Dunedin.
The blaze started at a private green-waste disposal in Burnside around 7:45am, and has been keeping 20 firefighters busy, including four engines and a rural tanker.
Fire communications shift manager Andrew Norris says it's more of a "smouldering heap" than a "big blazing inferno".
The cause is currently unknown, but spontaneous combustion is a possibility, having caused compost fires in the past.
"The compost process involves a lot of heat and one of these heaps has caught fire unfortunately," he says.
"They're using heavy equipment to break the heat down and extinguish the fire as safely as they can to stop it spreading to other piles."
It's currently contained to the compost pile area, but there is a stretch of pine plantation nearby which could be in danger if the fire was left to burn uncontained.