Humans cause most fires in Southern California

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Dry grasses surround a sign in Kagel Canyon that encourages home owners to clear vegetation that could fuel a wildfire from around their properties near Los Angeles, California.

While New Mexico has received enough rain to lift some fire restrictions, other parts of the Southwest are still dry. That makes them vulnerable to lightning-sparked fires, as well as human-caused fires, The Fronteras Desk reports.

Humans start about half of the wildfires in the Southwest. In Southern California it’s a lot more—about 90 percent are caused by people. Fire managers say closer to the bigger cities, where the population is dense, there are more human-caused fires. The top causes are unattended campfires, trash pile burning and arson.

Helene Cleveland is the fire prevention program manager for the U.S. Forest Service. Cleveland says many people will leave their campsite thinking they have put out their fire.

"A number of people will pour water on it and they think all the hissing has stopped," Cleveland said. "They don’t see any smoke or steam rising from it and they think it’s OK. But what’s happening is there are embers deep down in, dry weather comes back around, the winds will pick up and sparks will fly."

Dry lightning can act much the same way. Clay Templin calls them sleepers, when lightning strikes and the embers smolder until the wind picks up. Templin is fire chief for the Tonto National Forest. He says this is the time of year when both dry lightning and humans keep him busy.

"It just takes a spark, especially when we’ve had this extended drought that we’re currently experiencing," Templin said. "It doesn’t take much for a fire to quickly gain in size."

Since late spring about 95,000 acres have burned in Arizona.