Crews make progress on Oregon wildfire

The Bootleg Fire in Oregon is 40 per cent surrounded after burning some 70 homes.
The Bootleg Fire in Oregon is 40 per cent surrounded after burning some 70 homes.

The United States' largest wildfire is raging through southern Oregon but crews are scaling back some night operations as hard work and weaker winds helped reduce the spread of flames.

The Bootleg Fire was 40 per cent surrounded after burning some 70 homes, mainly cabins, fire officials said on Friday.

At least 2000 homes were ordered evacuated at some point during the fire, and an additional 5000 were threatened.

In central Montana, five firefighters were injured when a thunderstorm and swirling winds blew a lightning-caused wildfire back on them.

The fires are among many burning across the US West, where extremely dry conditions and recent heat waves tied to climate change have made wildfires harder to fight.

In Oregon, the upper eastern edge of the Bootleg Fire continued to move toward Summer Lake, jumping fire lines on Thursday and prompting an evacuation order.

Winds up to 16km/h could drive the flames through timber but not at the pace seen last week, when the wind-driven blaze grew exponentially.

The fire, which was ignited by lightning, had been expanding by up to six kilometres a day, pushed by strong winds and critically dry weather.

There was good news on the lower portion of the 1600 square-kilometre blaze. Crews had locked in containment lines and on the lower southeastern side, they were able to gain a substantial foothold, allowing them to cut back to night-time patrols.

On Friday, authorities said they would be keeping an eye on changing wind conditions.

In California, the Tamarack Fire south of Lake Tahoe has now burned more than 235 square kilometres of timber and head-high chaparral of mostly national forest land.

The fire, sparked by lightning July 4 in Alpine County, has destroyed at least 10 buildings and forced the evacuation of more than 2400 homes.

Australian Associated Press