As the title says, I am looking for ways to place forested hills and foothills on my regional map.

Full story, I am borrowing an area map from a D&D module and putting it into a slightly bigger regional map (basically a Duchy and the wilds beyond it). The map in the module has the elevation markers running through the forest to show it's trees on hills, but I wasn't sure I wanted to put elevation markers on my version. So I'm looking for icons or examples or brush settings to show that these trees are on hills. (Using a Wacom with Photoshop 2023.)