Photo: Sam White
A Fire Service spokesman said the trees, between 6m and 8m tall, were near Kaitangata.
Crews from Kaitangata, Balclutha, and Clutha Valley had been fighting the fire in Wangaloa Rd since 1pm.
The size of the blaze was unknown, the spokesperson said.
The helicopters were deployed as the area was difficult to get to by land, he said.
