This is true. Rural Vermont and New Hampshire have seen a lot of passive reforestation after farming moved to the Midwest. It took a few generations. It doesn'

This is true. Rural Vermont and New Hampshire have seen a lot of passive reforestation after farming moved to the Midwest. It took a few generations. It doesn't always work though. There has to be enough left that it can grow back. And there can't be, say, new grazing animals that prevent that from happening. I'm thinking of, say, Easter Island, or arguably some of the North Atlantic islands like Iceland, Greenland... maybe even Britain (the moors used to be forests in prehistoric times).