On Thursday controlled burn-offs at Warren Reserve and Watts Gully were ignited by a small incendiary device, which was lowered by a helicopter.

According to Richard de Groot, convenor of the Mt Lofty Ranges fire co-operative, this is the first for the state.

He said the initiative was a response from the devastation of the Victorian bush fires experienced early this year.

The new device, the size of a ping-pong ball, contains fire accelerant, which ignites when dropped to the ground.

“Historically drip torches have been used for burn offs,” Mr de Groot said.

He explained how the dense reserves made it difficult for fire crews to access certain areas, so a helicopter was used.

“The benefits of the dropped accelerant include covering a large area of dense vegetation and doing this in a safe and controlled way,” Mr de Groot said.

“We want to significantly reduce a fires’ intensity in the event of a bush fire,” he added.

CFS crews assisted on the day by controlling the fire’s border and working to reduce the reserves’ undergrowth.

The initiative is a co-operative effort of the Country Fire Service, Forestry SA, SA Water and the Department for Environment and Heritage.