SAN LUIS OBISPO COUNTY, Calif. - Fire crews are mopping up a 40-acre brush fire along Highway 166 west of the Cuyama Valley.
The "Rock Fire" started Wednesday afternoon on the Rinconada Ranch, according to Tom Rickard the owner of the ranch.
Forest Service and CalFire crews worked through the night and into the morning to keep the fire from spreading to nearby foothills covered with thick, dry brush.
The fire burned itself out along a wet creek bed.
No structures were threatened by the fire.
According to Rickard, the fire started after a motorist ran off the highway, flipped over in his field catching the field on fire.
It's unknown if anyone was injured in the accident.
Traffic in both direction on Highway 166 has not been affected by the fire.