Three teenage boys have been charged for allegedly lighting a fire in bushland in Sydney's west, which burnt through 10 hectares and needed 15 fire crews to extinguish.

Emergency services were called to bush behind Chestnut and Sedgman Crescent, Shalvey, about 1.15pm on Tuesday.

It took firefighters over two hours to put out the blaze, but noone was injured and no properties were damaged.

The State Crime Command's Arson Squad examined the scene.

Three boys were arrested nearby and taken to Mt Druitt police station, where they were interviewed.

A 14-year-old and two 15-year-olds were charged with intentionally cause fire being reckless to its spreading and also causing or setting fire to the property of another.

They were granted conditional bail to appear in Parramatta Children's Court on January 29.

smh.com.au