This is an archived article that was published on sltrib.com in 2015, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

Firefighters have begun reining in a central Utah wildfire, called the Solitude Fire, that's been allowed to burn itself out.

Twelve days after lightning sparked the wildfire, it's grown to 378 acres as of Saturday and is 40 percent contained. The fire is burning through timber in the Pahvant Range, which is about 10 miles northwest of Richfield in Fishlake National Forest.

After the lightning strike, the flames didn't spread much — until July 26, as temperatures climbed. The more energetic flames torched groups of trees at a time and spread uphill.

But instead of burning through the trees in a cleaner line, the fire formed a crooked path that's harder to control. When that happens, firefighters intentionally burn vegetation around the fire to create a cleaner containment line, said Jason Curry, spokesman for the Division of Forestry, Fire and State Lands.

"We burn inwards towards the rest of the fire," Curry said. "It's an efficiency thing. We have less ground to cover… Especially with a fire like this one, we can be sure the fire does a clean job."

Crews are managing the fire to improve the habitat, according to the Fishlake Forest Service. The blaze will remove some of the dead vegetation and create openings in the mixed conifer, which paves the way for aspen regeneration.

Twitter: @MikeyPanda