Planting that many trees is not what's required. What's required is growing and maintaining them. If they burn in a fire, you need to start over. If they get cut down, you need to start over. If the land they're on gets sold and redeveloped, you need to start over. Etc. I think this seems a lot easier than it is because the wrong language is being used to describe what is actually required. You need to bring into existence and perpetually maintain (even after your death) 172-572 trees. That is not easy.