The fire broke out about 1 p.m. off county Highway S-2 near the Butterfield Ranch, about nine miles southeast of Julian, and was headed upslope toward Sunrise Highway at a moderate rate of spread, according to Cal Fire.
No structures were threatened, Cal Fire officials said.
Firefighters had the blaze 10 percent contained by about 9:30 p.m., according to fire officials.
Sunrise Highway was closed at Old Highway 80, and state Route 79 was closed at Sunrise Highway, according to the California Highway Patrol.
The fire’s cause was under investigation, Cal Fire said.