2 Brush Fires Fanned by Dry Winds Scorch Yorba Linda : Emergency: Extra crews were sent to quell the pair of foothill blazes, which were exacerbated by weather conditions.

A pair of small brush fires, fanned by hot, dry Santa Ana winds, burned up to 7 acres in the Yorba Linda foothills Monday as the strong offshore gusts whipped up fires throughout the Southland.

Orange County fire officials sent extra crews to control the two blazes in the foothills, where winds reached 45 m.p.h. and vegetation was described as extremely dry. Officials feared the fires would get out of control and spread to thousands of acres of tinder-dry brush land.

Elsewhere, four homes were destroyed and two damaged in Diamond Bar in an afternoon blaze that started in brush at the base of a slope and burned uphill to homes with shake roofs and worth about $350,000 each, Los Angeles County fire officials said. No injuries were reported.

In Riverside, one house was gutted by fire and 17 others in the Anza Narrows area near the Santa Ana River sustained minor damage; at least 50 homes and a junior high school had to be evacuated. By evening, the fire had blackened at least 125 acres, much of it covered by heavy brush.

In San Bernardino County, fire raced through about 148 acres of brush-covered land along the Cajon Canyon foothills, briefly threatening the Tree House Fun Ranch nudist colony.

The first Yorba Linda blaze started at about 8:45 a.m. when gusty winds knocked down a power line near a Metropolitan Water District filtration plant at 3972 Valley View Ave., said Orange County Fire Department spokeswoman Kathleen Cha. Two acres were charred in that blaze.

About two hours later and less than a mile away, winds “arced” a power line, causing it to give off sparks that started a 3- to 5-acre blaze near 4024 Valley View Ave., where Shell Oil Co. has a pumping station, Cha said.

“It’s like a battle,” she said. “The winds are so erratic. . . . But we have been fortunate so far.”

Orange County fire officials sent out 10 engines, two bulldozers, a fixed-wing aircraft and two helicopters to battle the second blaze, said Jose Valbuena, an Orange County fire spokesman at the scene.

“It could have easily gone to 1,000-plus acres,” Valbuena said.

The blaze forced one crew to take off midway through the dedication ceremonies of a new, $1.6-million fire station on the east side of Yorba Linda, where a 3,600-unit housing development is being constructed. Plans were to display the station’s new engine at the ceremony, but it was taken to the fire scene.

Linda Bibeau, 31, who lives in a neighborhood where homes have shake-shingle roofs, said that at one point flames came within half a block of her house. She said that she was standing by to turn on a sprinkler system her family had just installed to wet down their roof in the case of such a fire.

“The response (of the firefighters) was great; it was really great,” Bibeau said. “But this one is a little too close to home. With the winds, all it takes is just one spark to light it on fire on the roofs.”

Both fires were controlled within an hour, Cha said, but fire crews remained at the sites for several hours to guard against any flare-ups because of the winds.

According to weather forecasters, hot, dry weather and gusty winds are expected to continue today.

“As far as temperatures are concerned, it will probably be in the low to mid-90s (today)--another hot day. And there will be a Santa Ana wind condition, though not as strong,” said Ken German, a meteorologist with WeatherData Inc., which provides weather forecasts for The Times.