Indonesia’s vast peat swamp zones have been widely drained and dried for agriculture and made highly flammable. In the dry season they burn uncontrollably when farmers and companies use fire to clear land. Last year’s fires sent toxic haze billowing across Southeast Asia, polluting the air above Singapore, Malaysia and other countries. They sickened half a million people in Indonesia and emitted more carbon than the entire EU during the same period. To prevent another crisis, President Joko Widodo has ordered a law enforcement crackdown on illegal burning, and already the police have arrested hundreds of people. Indigenous tribes who have relied on slash-and-burn for centuries, however, say that they need to be allowed to keep burning, and that they may face a food crisis if they cannot. Come August in Kapuas Hulu, West Kalimantan, it is time for the indigenous Dayak Iban to burn the land and plant the dry rice, or ladang, that will feed them the following year. “If we don’t plant ladang, we don’t eat,” said Apay Hudi, a lithe, silver-haired resident of the Sungai Utik longhouse, pausing as he fastened a new handle to an old, rusty field machete. He said local officials were trying to wean the community off ladang and onto wet paddy cultivation, but irrigation challenges meant the fields weren’t ready. Needing ash for fertilizer and lacking suitable alternatives, Hudi said burning for ladang was a fait accompli. “Besides burning, there’s no other way for us to plant it.” The government sees things differently. One afternoon a few weeks ago, military men showed up at the longhouse with a warning: Stop the ladang burning or face fines, even jail time. Dozens of Dayak tribes in the area have been given a similar warning, as have farmers across the country — part of Indonesia’s crackdown on the annual scourge of haze-belching agricultural fires. Collectively, these Dayak tribes occupy a sixth of the district of Kapuas Hulu, a 28,000-square-kilometer chunk of lowland forest at the eastern edge of West Kalimantan province, deep in the heart of Indonesian Borneo. Though these homelands have been mapped, they are not recognized by the government, meaning communities like the Iban are on constant guard for encroachments by oil palm plantation firms. Twenty-eight Iban families live in the Sungai Utik longhouse with Hudi, one of several customary Dayak homes still standing in the district. The space is a marvel of interdependence: in the 200-meter-long foyer, young and old make handicrafts and prepare food by day, waiting for groups tending the fields and foraging the forests to return home. In the evening, adults gather to sip ijuk, a sap drained from the enau tree, and chat well into the night.