A new wildfire is burning about 35 miles southwest of Butte, near the community of Wise River.
Forest Service officials say the Byway Fire started at around 1 p.m. Tuesday, and it is burning at 300 acres.
It is no longer threatening structures, although it did initially.
Beaverhead County and the Forest Service are tackling the blaze, using 10 engines and three watertenders.
The fire is burning a mile-and-a-half from Wise River, near the Pioneer Mountain Scenic Byway.
It is not known what started the blaze.