There is a way!
You must find a piece of nylon rope!
This rope is actually made,from many tiny fibres.
So with tha help of a scissor,you cut at about any length you want.
Just think,how tall you want the grass be.
With this method you can made as many as you want and at any length.
Here what you can do at 1/72 scale
http://img154.echo.cx/my.php?image=m11334px.jpg
http://img97.echo.cx/my.php?image=m11322fi.jpg
http://img179.echo.cx/my.php?image=m11312tt.jpg