Follow up question: Can you plant trees?

Yes. Be careful when driving fast, some newly spawned trees on erosion roads may wreck your car, and you.
You can't plant trees in vanilla game.

Erosion will make nature slowly reclaim everything. Well, in PZ's case not so slowly. The normal erosion speed in the game is insanely fast. Wall crack, vines envelop houses and entire forests spring from the ground in mere months. If anything, you'll need to slow erosion down considerably to make it even a bit realistic.

No, you can't plant trees but with the current settings you'll have more trees growing all over the place than you'll know what to do with.

2 month and u c the infestation progress