A ground based drone is orders of magnitude simpler than a multirotor. There is nothing magical about multirotors except being the latest fad for tech geeks. A

A ground based drone is orders of magnitude simpler than a multirotor. There is nothing magical about multirotors except being the latest fad for tech geeks. A ground based drone — eg a modified bulldozer — can carry far more plants as cargo, meaning planting a field of a thousand sapling might require one trip where a flying drone will require a thousand trips. The only catch is access: for a remote region with no trails of any kind it might be difficult for a large vehicle to navigate through the forest. In this case clearing a path for the planting machine might be a lower cost to the environment than the energy required to fly a thousand sorties with flying planters. A ground based drone will also be able to plant more robust saplings, since payload weight is far less of a concern.