This is not possible.

We designed our app in such a way that when data is deleted, it is gone forever. We have done this for a couple of reasons: the first is to save on data costs. The second is that, according to EU law, you have the right to read, edit and delete your data. And that when you want your data deleted, it really is deleted. So all your forests, images and user data are gone and there is no way to restore it.