Weeds and stuff. Decaying and dead scrubland foliage, easily stuck to terrain or figure bases to add that little extra bit of detail. Grass colours and lengths vary appropriately. No glue required, although may be required on some finishes or plastics.
To apply, simply peel the tufts of grass from the backing sheet, preferably with a pair of tweezers, and place on your model or scenery. These are self-adhesive, and will adapt to odd surfaces most of the time.