Skill level 1.55 recently viewed a YouTube video out of Australia where a modeler used a new brand of static grass applicator.  I purchased the unit, a Woodland Scenics Static-King, through the HoH.
Most units use a 9 volt battery but this one can also utilize a 12 volt transformer…which provides a higher output voltage.
Briefly, paint the base brown so if there are any bare spots it looks like dirt,  add your static grass (2-12mm long and all different colors) to the hopper, apply glue to your diorama or vignette, set the ground wire, turn the unit on, and from a height of .75-1”, shake the grass out over the glue.  The static electricity makes the grass stand realistically straight up. 
This is the most effective unit I have used.
Here is a photo.

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