I wonder if currently such areas are decided by checking local geo data or physical surveys only instead of some sick machine learning and sat data. I know arable lands are monitored and can be prospected via sat data but I am looking for how to detect the best areas to try reforestation with a good degree of certainty that the reforestion is doable by sat data, before actually experimenting with the reforastion process in those places. I suppose this should involve a combo of terrain composition + land chemicals + rainfall data + wind patterns + actual green areas nearby + human presence + local tree species characteristics + historical tree coverage?