> Not surprisingly, those locals often reacted badly. For example, in northern Malawi, they broke fences and burned a growing forest to get back the common grazing land on which the trees had been planted. In two Nigerian projects, villagers cut all the planted non-fruit trees for firewood, while protecting those that bore fruit.
Recommended reading: "Seeing Like A State" by James Scott. The first section on Scientific Forestry directly applies, and the rest of the book conceptually does too.
In summary, the state seeks to render its resources and populace legible, because local arrangements are very hard to quantify (and tax) from the center. This drive to achieve legibility inevitably distorts the world they are attempting to understand, for example by incentivizing monoculture forestry (easier to count the trees) instead of natural forest growth (providing many communal resources that are impossible to measure such as firewood, foraging, grazing, and so on).
There is a very prevalent idea that "subsistence farmers" know little about the land they work. It's usually the opposite; they tend to have far more practical expertise than the centralized planners.
If instead of planning these projects centrally, they were planned and executed by locals in collaboration with central funding sources, you'd be much more likely to get good results. The local farmers can usually tell you what trees will grow, where they will survive, what the village needs more of, and so on. To be more concrete -- why not provide a centralized program that subsidizes villages to plant trees, but does not specify which trees to plant? If the incentives are high enough you'll get people to plant anything (as the OP shows). But at a lower level of incentive, they will only do the work for something that they actually value. That's the sweet spot.