That's how it works in haven and heart iirc. In Salem, no need to plant the correct trees. Just dig up the soil. New terrain will form over it.
Only terrain types that are in direct contact with the dug up soil will regrow there. Some creative digging, and paving to keep the wrong biome out will allow you to change any biome into any other biome that is near you. You an even turn your entire base into wildlife trail this way, if you have one nearby.
As for the OP, yeah it's been suggested a few times, and as already said, it's still a good suggestion, +1