The fire began around 8:15 p.m. Thursday night, KGO-TV, San Francisco, reported.
No evacuations have been ordered, but the fire has threatened five structures.
By 11:45 p.m., authorities said the fire was 75 percent contained and that the spread of the fire had been stopped, the San Francisco Chronicle reported.
Residents in the Bay Area are smelling smoke from the fire, which is northeast of Lake Berryessa, KGO-TV said.
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