Doc area manager Paul Hellebrekers last night said a "significant area" of the Craig Burn reserve burned, but it was too soon to assess the damage, which included areas of regenerating beech forest.
Large teams of firefighters from the voluntary Lake Hawea, Luggate and Wanaka brigades supported the Doc firefighters at the scene.
Private contractors and the Queenstown Lakes District Council provided water tankers.
Because of the fire's intensity and the steep, inaccessible terrain, five helicopters using monsoon buckets were used to douse the flames.
The firefighters retired for the night about 8pm, and while the fire was still burning, it was "not threatening" and Mr Hellebrekers was "reasonably comfortable with the way things are going".
Doc chief rural fire officer Paul Hondelink expected the Doc crew could be there all weekend, but an assessment would be made this morning, with a crew returning at 6am.
The weather forecast for cooler weather and snow in parts of the region today could help the situation - if the colder weather arrived.
The fire started when a permitted burn on Glen Dene Station was fanned by a northwesterly wind and escaped into the Craig Burn gully, a popular tramping and hunting access route into the Matatiaho Conservation Area.
Station owner Richard Burdon was away but his father, retired farmer Jerry Burdon, was quickly on the scene. Mr Burdon said the fire alarm was raised by an employee about 4pm. The employee also called local pilots Toby Wallis and James Ford.
Mr Burdon was clearly upset and anxious as he stood above the gully with firefighters and watched the fire spread.
Controlled burns were a good land-management practice, helping prevent larger vegetation fires in the summer, but he would not want the reserve fire to happen, he said.
The Matatiaho Conservation Area was created when Glen Dene was freeholded during tenure review about six years ago.
Mr Burdon said the beech forest had been regenerating for at least 28 years. He believed the gully had last been burned about 40 or 50 years ago and it would heal and regenerate.
