A vegetation fire in a remote area between Guerneville and Rio Nido had spread across an estimated 2 acres of dense forest by Thursday morning, according to Cal Fire.
The blaze was reported at about 8:30 p.m. on Wednesday.
The cause was unknown to fire officials on Thursday morning, said Cal Fire Captain Aaron Loscar.
It ignited in an undeveloped area between River, Armstrong Woods, and Rio Nido roads. Nobody was evacuated and no homes were threatened, officials said.
Firefighters were monitoring the blaze throughout the night and Cal Fire planned to continue suppression efforts throughout the day on Thursday, according to Loscar.
“Trying to make access to it was really difficult last night,” Loscar said. “There are no roads that go there.”
A helicopter crew with the Sonoma County Sheriff’s Office flew over the blaze Wednesday night and relayed an estimate of its size to fire officials, according to Loscar.
“Now that we have daylight we can actually see what’s going on,” he said.
You can reach Staff Writer Matt Pera at firstname.lastname@example.org. On Twitter @Matt__Pera.