@Rondidon: nice!
use grass models instead of grass sprites. I use 24 poly models based on Loopix scattered grass model, with weighted randomized clipping at 1st and 2nd lod distances, and works fine in huge quantities. I use sprites only as details like flowers what can be swithced off easily on slow pcs.

@ratchet: I use 8 poly models for far tree lod models. how is it possible to use oriented sprites as lod stages of models?