Hi. On The task manager, you can read what to be mapped. (symbols)
Often, there are several projects on the same spot. 1 for roads, 1 for buildings.
The project manager decides what to be mapped. You are not forbidden to map buildings, but for the sake of the progress we ought to follow the instructions.

About hedges, use common sense. In the open areas like here, you will not find walls.
Best regards and keep mapping