Maradi, NigerFor centuries, rich woodlands dotted this dusty, sun-blasted region south of the Sahara. There were fat locust bean trees, wispy bushes, and sparse pockets of winter thorn and tamarind. By the time Ali Neino was a boy in the 1980s, however, just one lonely tree sprouted from his family’s land, and he could see clear to the horizon.

“There was no vegetation in between the village and the fields,” recalls Neino, 45. “No trees, no shrubs, nothing.”