THE firestorm that turned hillside mansions here into a moonscape has raised pointed questions about everything from fire training to roofing materials.How can such blazes be prevented in the future? Should more be spent on firefighting? Why do people keep using wood-shingle roofs? The soul-searching is most intense in this benumbed community. But similar questions are beginning to reverberate throughout California, as the depth of the destruction here - more than $5 billion, the most of any fire in United States history - becomes apparent. Even without a five-year drought, California is the nation's most combustible state. Long, hot summers, coupled with dry fall winds and tindery vegetation, make fire an ever-present danger. The continued migration of residents into rural areas exacerbates the problem. "California has an ecology that is just built to burn, " says Karen Terrill of the state Department of Forestry and Fire Protection. "The fire-flood cycle has always been alive." The Oakland fire, which consumed more than 2,500 dwellings, underscores what some experts consider the growing threat of "wildland" fires in urban areas. City fire departments, like Oakland's, are set up more to fight structural blazes. Fires in wooded areas require different tools and techniques, experts say. "There needs to be more cross training," says John White, a coordinator with the respected fire science program at Shasta Community College. He believes greater use of such things as bulldozers and hand crews creating fire breaks might have aided in suppressing the fire here this week. But local fire officials say that some equipment wouldn't work in the hills and steep canyons of Oakland, and they maintain that no amount of firefighting capacity or technique could have checked the wind-whipped inferno. Debate is also sharpening over the amount of money being put into fire suppression. The state recently cut $4 million from its fire protection budget, though Gov. Pete Wilson, who has been highly visible here this week, denied that lean times have inhibited the Department of Forestry's ability to fight blazes. Similarly, Oakland officials have been criticized for budget cuts that have reduced the number of firefighters in the city from 622 in 1974 to 424 today. But local officials, again, deny that more manpower and equipment could have helped control the intense fire here. The questions come as survivors started getting their first glimpses of what is left of their neighborhoods. The scenes were emotional; families looking through rubble for anything that might have survived: a man walking out with a strongbox whose contents were vaporized; a woman looking for her cat that was left behind. Inexplicably, the tongues of flame jumped over some houses, leaving them untouched, while everything else in the area was reduced to soot and twisted steel. Some residents talk of rebuilding. Others want to start over somewhere else. To try to avert such scenes in the future, some local lawmakers are calling for a fire station to be built in the Oakland hills, to cut down on response time in the rugged terrain. Landscaping and zoning regulations are receiving fresh scrutiny. State forestry officials would like to see more greenbelts - golf courses, parks - built around housing developments. Bay Area environmental groups go further than that: they want development stopped altogether in the area's open hills and canyons. The biggest battle, though, may come over building materials that homeowners like for the way they look but are potential fire hazards. Several state lawmakers plan to renew their push for a ban on new construction using untreated wood shingle and shake roofs. Similar efforts have been defeated by the real estate and shake roof industries in the past, though bans have been enacted in some local areas. "I still think wood shingles will continue to be a hard issue," says Mr. White. "Aesthetically, people really like them."