LOD grass

Almost all major titles contain grass that only appears once the player is within a certain distance of it. How exactly would you achieve this with the LoD feature in bge? would you create an object and then delete the mesh so that there is nothing there? or would you replace it with an object that is invisible?
what would be the best way about doing this?

together with this I’m guessing the effect would be duplicated for each ‘section’ of grass (say 10 clumps joint together)?
How expensive is LoD if it was to be applied to each clump of grass (say 10 pieces joint together)?

The walkable terrain (in my opinion) should not have LoD applied because if one is misplaced even slightly the player has chance of falling through the map.

There is an LoD function in the newest version of blender, however it is only applied to the camera’s distance from the object. I have always created my grass, and then created another object and deleted all the vertices; then duplicated the grass and grouped them. Then in blender render made a particle hair system with groups. I hope that helps! I love your youtube videos, and I am subscribed keep up the good work, your videos got me off my feet in blender. Thanks