If you’re looking forward to fireworks over the July Fourth weekend, you’re probably not a firefighter or someone with a house next to a tinder-dry patch of woods.

More Americans than ever are living in or near fire-prone forests. The territory some researchers call the “wildland-urban interface” grew by 61 percent between 1970 and 2000, according to a recent analysis. Add a rising global temperature and depleted snow packs, and you’ve got a recipe for lots more devastating wildfires.

Even with more federal funds going to fight fires, many believe the resources aren’t keeping up with the rising risks. The Boston Globe reports today that some wealthy homeowners are hiring private firefighters for additional protection, while California Governor Arnold Schwarzenegger is pushing a “fire-fighting fee” on home insurance in the state, according to the San Diego Union Tribune.

A study published in the journal Ecological Applications last week explored the complex relationship between global warming and wildfire risk, suggesting that the creation of dry vegetation influences a fire’s destruction more than rising temperatures themselves. A case in point would be Western shrublands and grasslands, as they require a wet year, followed by a dry one, to produce the kindling for a large wildfire.

Those findings piggyback a paper released in the May issue of Ecological Monographs, which looked at historical data on fires from 15,000 B.C. to the present. Researchers found that certain types of plants compensated for heat’s increased threat. A dry climate 10,500 years ago, for example, actually resulted in a decrease in fires as fire-resistant deciduous trees had replaced flammable shrubs.

As if things weren’t bad enough already, hungry bark beetles pose a growing danger—more dead trees means more fuel for fire. The beetles have rendered at least 7 million acres of U.S. forest “all but dead, throwing a swath of land bigger than Massachusetts into a kind of fire-cycle purgatory,” The New York Times reports.

Photo by Calc-tufa via Flickr.