The easiest, most common alternative is a mix of textured 2D planes per shrub. This is the norm these days.
Seems like a total waste of resources to me. I mean, are you actually going to be driving around those shrubs to notice that it's multiple textures ala. Oblivion? No, you'll be screaming past them at 100 miles an hour.
Generally I concur, though the extra required resources aren't a huge amount, and when you allow a free camera in pause mode, the 2D sprites really stick out. If there was no pause-and-view mode (which every game should have IMO!) I probably wouldn't have noticed, as the shrubs are whizzing past at a hundred miles per hour!
That mud has improved tremendously and is now looking awesome, I see. I can't believe how wide-open the track is, it's HUGE!!!
