Traditional burning practices are under scrutiny by scientists and policymakers because peatlands are effective carbon sinks. They are made up of layers of decomposed organic material built up over thousands of years. When they burn, warming gases are released into the atmosphere exacerbating climate change. Fires often burn out of control, damaging vast areas and drying out the land, rendering it useless for farming. In 2015, the impact of wildfires was far reaching. Fire destroyed more than 2.6 million hectares of land — an area 4.5 times the size of the Indonesian island of Bali, according to the World Bank. The price tag for the damage was more than $16 billion, the bank said. Indonesia has since boosted efforts to ban the use of fire to clear forested peatlands to plant oil palms, maize or rice by establishing the Peatland Restoration Agency in 2016.