Cant plow ground

[Savaura]

There are a few spaces where there was previously a chicken coop on the ground and I wanted to rebuild it on stone... but the plow wont enter the space as if it is running into something, and I can't plow it manually. I can walk through the space but cant alter it

[dagrimreefah]

It's probably because it is a tile that has been eaten away by animals. Its a totally different type of tile, even though it looks just like a normal dirt tile.

Solution: Plant grass over it, then plow it.