The incredible plan to make money grow on trees | Sam Knight

One of the most cutting-edge projects to tackle climate change is being pioneered in one of the most remote, undeveloped countries on earth. Does it have any hope of succeeding? By Sam Knight

One day about five years ago, Frank Nolwo, a compact, quietly spoken boat skipper from the upper reaches of the Sepik river, in northern Papua New Guinea, woke up and headed into town. Nolwo, who is 42, has nine children. He was adding an extension to his house, and needed to buy some building materials.

You do not just pop to the shops if you live in the upper Sepik. Nolwo left Kagiru, his village, in the early morning. Like other isolated clutches of palm-roofed houses on the river, Kagiru has no electricity, no mobile phone signal, and no road connecting it to anywhere else. Even by Papua New Guinean standards, the region is regarded as hot, poor and difficult to live in. When it rains, the place floods. When there is a drought, the creeks and streams dry up, stranding people and their canoes. It takes days to walk anywhere. For powerful, almost unarguable, geographic reasons, life in the upper Sepik has resisted meaningful economic development for thousands of years. There are lots, and lots, of crocodiles.