The underlying problem is humans harvesting wood. >I would be sceptical about using this to stop desertification. Take a closer look at the Permaculture movem

The underlying problem is humans harvesting wood. >I would be sceptical about using this to stop desertification. Take a closer look at the Permaculture movement and the extremely effective science developed around that scene on the subject of stopping desertification - where this article specifically mentions trees being dropped from the sky, that's merely the outer limit. Grassland-dropping drones would also be effective - its not just trees-as-species, but all the other bio-sphere in between that matters. Farmers using drones to drop mantis-packs is another potential use .. the sky is literally the limit. What we don't have, is the drone systems that can be readily deployable. Yet.