I was curious enough to look at this story a bit more. Some related, interesting tidbits: In 2004, Niger estimated 50% of farmland was using the farmer managed natural regeneration framework (FMNR) described in the article, essentially reforestation through growing new trees from sprouts on old tree stumps [1]. An update in 2022 says over 200 million trees have been added via FMNR [2].
Yes, I was looking for the 'gotcha' when I searched the wiki but none is there. Seriously impressive stat, from a decidedly low-tech yet seemingly still relevant method.