Earth : Green

A post apocalyptic setting where the world as we know has been covered in seemingly endless forest. The woods are so dense the ground at their roots is unhabitable, and ground vehicles can no longer get around, roads having been swallowed and destroyed by the roots. Humans have all moved to cities, now reinforced to resist the slow destruction. Bigger, richer towns thrive on aerial communications, but smaller settlements who cannot afford it turned into lonely bastions. The air is warm, the sky is clear, and if you sit atop the walls, you can see a moving sea of green.