document: As of last month , live pines in the Mount Palomar area near San Diego had less moisture than boards at a lumber yard. ; Firefighting also will be made tougher this year because much of the military reserve and National Guard equipment and pilots normally mobilized against wildfires are still in the Persian Gulf and probably will be there several more months. ; The area at risk of severe fires spreads beyond California and takes in about a third of the United States mainland , including Oregon and Washington east of the Cascades and much of Nevada , Arizona , Utah , Colorado , Wyoming , Idaho , Montana and the Dakotas. ; But the threat is most extreme in California , where the December freeze added to the accumulation of dead vegetation , or fuel , as firefighters call it. ; While reluctant to predict fires because they depend not just on drought but also on temperature and wind patterns , fire officials are deeply worried. ; `` This year is shaping up to be the worst fire season we 've ever experienced , '' said Warner McGrew , assistant fire chief at Santa Barbara , where the drought is worst and where brush fires destroyed 600 homes and did $ 200 million damage last year. ; The freeze killed the avocado and lemon orchards that used to serve as fire breaks , and McGrew said fire codes are being strictly enforced to compel homeowners to remove vegetation near houses. ; Given the severity of the threat and lack of equipment and water to fight fires , officials throughout the region say they plan an unusually aggressive approach this spring , trying to put out even the smallest wildfires before they spread , and taking preventive measures such as deploying firefighters to an area where lightning storms are forecast. ; It worked in Oregon ; That approach helped last year in the Umatilla National Forest in northeastern Oregon , where 170 fires were reported , said Gordon Reinhart , a fire and recreation officer with the U.S. Forest Service in Pendleton , Ore. ; One reason the fire threat is so grave in California is population growth , which has spread suburban development into wilderness areas such as the canyons east of Malibu Beach , 25 miles from central Los Angeles , where million-dollar homes sit on brushy hillsides covered with highly flammable greasewood. ; Fire corridor ; Fire officials consider the Malibu canyons a natural fire corridor because high winds whip through them to the ocean. ; `` We are going to have quite a time trying to protect those structures , '' said Paul H. Rippens , assistant chief for forestry at the Los Angeles County Fire Department. ; The department is clearing some areas by setting small fires that are tightly controlled , the first of which recently burned off 335 hillside acres in the Monte Nido area of Malibu. ; Expand youth corps ; Gov. Pete Wilson has proposed expanding the state 's youth conservation corps to replace the troops who traditionally have stepped in to help fight the worst Western fires. ; But it will be difficult to replace the C-130 planes that are converted into air tankers to drop retardants onto flames , and the military helicopters with infrared sensing devices that peer through smoke .
extractive_keyphrases: firefighting wildfires california firefighters brush fires aggressive approach preventive measures fire threat severe fires spreads fire season natural fire corridor