Fire cutting activity is believed to have sparked a blaze in the Koondrook forest on Saturday which was finally brought under control after burning about 30 acres.
It is expected to continue burning and smouldering for at least a week, and is being monitored by Forestry NSW staff.
The fire has prompted warnings from the Mid Murray Rural Fire Service to be careful when collecting firewood ahead of the winter.
While an official cause for the blaze has not been determined, Mid Murray district coordinator Gerard James said the most likely cause was chainsaw activity in long, dry grass.
He did confirm there was no evidence of a campfire in the area of the blaze, which started in a heavily timbered area.
“The fire was discovered in the Crooked Creek section of the forest, which is closer to Barham,” Mr James said.
“The Barham brigade responded about 4pm and worked until it was dark.
“Heavy machinery was required in firefighting efforts, and the site is now being managed by Forestry New South Wales.”
Mr James said the fire is giving off a lot of smoke which, under the right conditions, could blow over other nearby communities until full extinguished.