I can describe the process better with the help of the picture below.
-First go to the tab Terrain, then the sub-tab Face, then select the tool "Texture Coordinate Mapping" (see three red boxes which lack numbers at the top in the picture).
-Then 1. New mapping , then select Cylindrical. You can name it whatever you want.
-First mark all faces of the whole area you want a cylindrical mapping for, using the Face Region Select tool (right beside the box numbered 4), in this case probably the slightly-vertical sod area or whatever you want to call it. Then press 2. "Add To".
Then press 3. Move To Center. You likely have to scroll down by clicking the little arrows in order to see that button. You can now de-select the faces, which will make it easier to see how things will look.
Then press 4. the Gizmo tool - which enables us to see and quick-edit a visual representation of the mapping. Then you can press the different attributes in the Gizmo action box and then hold left-click and drag in the views in order to manipulate the mapping (based on which of the XYZ axis you have selected in the views). Uniform Scale will likely need some adjustment until it looks good, Constrain Scale can be useful if it is a very oval bunker. Move up and down on the Z axis can also be useful depending on the texture used.
You can also try different values of 5. U Wrap, which sort of determines how the texture is stretched horizontally versus vertically (when viewed from the side). I think the default value is 1.0, which rarely is ideal if I remember correctly. I used 20 in my example but I only used the ugly default textures so it still didnt look that good when viewed up close...

- Cylindrical Mapping.jpg (556.59 KiB) Viewed 4716 times
The textures can be seamblended as usual.