I was never quite pleased with CGI-Grass and the results of Grass-Tutorials, because IMHO the grass was too even and the grass blades too simple, so I went ahead and tried something on my own (rendered with Cycles, GPU).
It’s still a long way to go, more variations of grass blades and textures, more tweaking of the shader, colors and light, more tweaking of the hair-/particle-system options and so on …
To me it looks like a wheat field. Grass grows in clumps from one common root. It does not grow exponentially like say trees or various plants. The shader however I think is really great.
You are right of course. I made the grass blades clump in the particle options before I rendered it… but those clumps got lost as soon as I turned up the particle-number.
I tried to fix it and updated the pictures in my initial post. I’m not yet statisfied with the clumps… but I just had an idea.