CBS News Correspondent Stephan Kaufman reports 17,000 residents have been told to evacuate if the Florence and Sour Biscuit fires become one and overrun several communities.
The firefighting crews are working together in Cave Junction, Oregon, said fire information officer Carol Jandrall.
"We are trying to build that line along this community," she said. "We're working on the north end and they're working on the south end and the goal is to meet, so that we have a big line of defense."
If the Sour Biscuit fire combines with the much larger Florence blaze, it would create a single wildfire nearly 200,000 acres in size.
In California, meanwhile, firefighters struggled against strong winds and rugged terrain as they tried to get a grip on a wildfire that has destroyed a handful of homes in the drought-stricken mountains east of San Diego.
Crews spent all of Wednesday dousing flames on the ground and in the air. Many also worked through the night setting back fires in an effort to clear the brush that is fueling a fire that has forced the evacuation of hundreds of people, destroyed five homes and killed four wolves at a wildlife center.
"It's still a dangerous fire," California Department of Forestry spokeswoman Tracy Gouette said Wednesday at a command post outside Julian. "There's a lot of fuel out there. It's dry, it's hot, and we're starting to get more wind...and that's always a concern."
Oregon firefighters hope to start a back fire, and clear brush to prevent the wildfire from storming down Cave Junction's main street.
"They're working on the power line roads, and they're bulldozing it to reinforce these lines, they're clearing brush under them," said Jandrall. "That's going to be our line to keep these fires from heading into the community."
"We have the lines in place and the people in place," said operations officer Bill Bowles. "It's just a matter of the weather coming together to make it all happen."
Holding the top priority in the nation for scarce resources, fire commanders called in more helicopters, bulldozers, hotshot crews and top-level management teams to quell the fires burning out of control on the Siskiyou National Forest in the southwestern corner of Oregon. In all, three of the nation's 16 top-level management teams are on the fires.
Although half a dozen people have been killed this year fighting western wildfires, firefighter Cody Gleason said he is not scared, because safety is a team effort.
"Everybody tries to keep their heads up for everybody else," he told CBS Radio News. "Our crew boss pretty much watches out for us all day long, making sure that there's nothing like a snag or anything that's going to fall on us."
Gleason said saving other people's property is his greatest reward.
"Twenty-five years ago, I had a home burn in the Los Angeles National Forest, and I'm not going to have that happen again," resident Bob Bell said Wednesday while using a fire hose to douse the grass beside his house on the outskirts of Cave Junction. "I've got a pond in back that's seven feet deep, and I'm going to jump in it," if the fire comes.
As of Wednesday evening, the Josephine County Sheriff's Department said only some 400 of the Illinois Valley's 17,000 residents had registered with the Red Cross as having left the valley. Residents have been told they may have only a half hour's notice to evacuate.
Pickup trucks and trailers loaded with household goods have been trickling out since the fires exploded on Sunday, sending up a 30,000-foot plume of smoke, but as the fires have calmed down, most residents seem to share Ron Brood's sentiments.
"We're going to stay here until they tell us it's time to get out," the retired high school principal said at his home outside Selma. "Then I'll turn on the sprinklers on the perimeter and get out."