Thanks all. The masking of the sand (rock debris) is done with Daniil's erosion shader.
2 versions of the newer guys, but same sky. To get the light like this I used 2 suns, one for lighting the clouds at 3º and one for lighting the ground at 12º. Fake, but well....
Mostly XFrog Prehistoric, but for the front stuff and some ordinary grasses. Rendered in 27 mins at 0.6 and AA6, soft shadows on, so surprisingly fast despite the V3 clouds.