A large pile mulch continues to burn in the Myrtle Creek area, 25km south of Casino.
Nine Rural Fire Service units and 30 people using heavy machinery have been working to pull apart and extinguish the burning mulch.
The efforts of firefighters have been hampered by strong winds creating spot fires in nearby piles, grass and bushland.
The fire is currently contained to the immediate area and conditions will improve into the night to bring the fire under control, a NSW RFS Northern Rivers Zone spokesperson said.
Tomki, Casino, Caniaba, Woodburn and Casino East units have spent the afternoon trying to put out the fire.
The spontaneous combustion fire happened on a working farm and the workers were able to help with the machines.
The fire was caused by large piles of mulch getting wet and then heating up and burning from the inside out.
Photos: Mick Stain
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