The fire was reportedly burning on a slope.
No structures were reported threatened.
The fire had burned 3 to 4 acres by 6 p.m. Thursday.
Two "super-scooper" water-dropping airplanes were called to the fire. At least two water-dropping helicopters were also assisting in fighting the fire.
Authorities dubbed the blaze the "Colima Incident."
Firefighters were taking defensive measures in case structure protection was necessary.
No injuries were reported.
The cause of the fire was under investigation.