This is looks like an interesting technique/method: (note the link is to a German forum)
http://www.kostenloses-forum.com/board/buesche-basteln-,nxu,01642644nx1878,t,1613.html#11304 (http://www.kostenloses-forum.com/board/buesche-basteln-,nxu,01642644nx1878,t,1613.html#11304)
The pictures pretty much explain everything, but in case you missed it the builder is using an electrostatic grass machine (like the Noch Grass Master) to apply static grass to the adhesive coated armature.
Marc
A unique looking bush. If you would be so kind Marc, as to translate what the use is of WD-40 in the very last sentence.
He uses the WD-40 to clean his tools & fingers from the adhesive, and the material he used to cover/create the shrub.
Marc