Gunnedah's firies have on Thursday contained a fire and saved a large hay shed in the process.
Rural Fire Service (RFS) crews managed to control the situation at a property on Wean Road, with only a loss of a few bales of hay.
Liverpool Range RFS district manager Myles O'Reilly said one hay bale below a stack of others might have self-combusted, causing others to be damaged.
"The bale has been protected by other bales, and crews in attendance have taken hay bales out of there to get to the bottom," Mr O'Reilly said.
"It's not an unusual occurrence."
Gunnible RFS' Geoff Hood said in the shed of 500 bales, there were 20 on fire and 60 moisture and heat affected.
The fire was listed on Fires Near Me as a structure fire, but Mr O'Reilly said the shed was "still in tact".
No one was hurt in the incident.