Tehachapi, Calif. ? Hundreds of firefighters gained ground Wednesday against the most destructive of two big wildfires that have burned homes and forced 2,300 people to evacuate mountain communities on the edge of the Mojave Desert and in the southern Sierra Nevada.

A 1,436-acre blaze that chased residents from the Old West Ranch community about 10 miles south of Tehachapi was 25 percent contained. Fire officials hoped to have it fully contained by Friday, California Department of Forestry and Fire Protection spokesman John Buchanan said.

The firefighting command revised the number of destroyed structures down to 25, and Kern County Fire Department Battalion Chief Dean Boller said most were homes.

Fire officials initially estimated 30 to 40 homes were lost. Another 150 homes in the loosely connected community remained threatened.

The area is usually so gusty that wind farms line ridges, but Wednesday afternoon the weather was cooperating with the 800 firefighters on the lines, producing only light breezes.

Patches of brush burned among spinning windmills at one energy site, but firefighters were keeping them contained and there appeared to be no damage.