Here is a simple method I use to add CG grass in Versus II background shots.
1/ Feed your scanner
2/ Edit alpha et diffuse map
3/ Apply map on a plan converted to editable poly, move some vertex, move the point of pivot at the bottom of the plan
4/ Distribute plans with a particle flow system, 3 kind of grass plan were used here to add randomness
5/ And voilà, quick scanline render (with domelight script) variable plan size
