You want newspaper, not astroturf!!!
Newspaper is cheap and clean and easy to replace.
Astroturf, or what some petstores sell that is kinda like it - basically a wool mat - can tear up the snake's belly. I haven't used actual astroturf, but I have used the wool mat I was talking about, and I was very diasppointed!! It was not as easy to clean as you might imagine, and I'm not kidding, it tore up my snake's belly scales! The best way I can think to explain it is that the wool fibers caught on the snake's belly scales in small spots, and caused something like a "hangnail" on the scale... but she was living on the wool mat, and had countless "hangnails" on her belly. She developed a problem shedding (which I soaked her to help with)... and then a skin infection. I spent a while treating her with antibiotic ointment, but immediately removed the wool mat and switched to newspaper.
IMO, newspaper is much better than the wool mat thing, astroturf (which I see as harsher than the wool mat), or any kind of wood chip/shaving substrate. I know LOTS of people keep their snakes on wood shavings and have no problems - but every once in a while something does happen.
If your snake really seems to miss having something to burrow in, try Spanish Moss; I put a 2-3" layer of Spanish Moss down on top of the newspaper substrate for the Dumeril's Boa I have. You can buy it at any gardening/home improvement store for fairly cheap. It's a little decorative, smells nice, and won't give the snake any splinters. It can also hold some humidity if you mist it. I suggest freezing a package of Spanish Moss for about a week before you intend to use it, just in case there are any bugs.
Good Luck! I'm glad you got the substrate out of her mouth!
~Rebecca

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0.1 Dumeril's Boa '04 (Courtney)
1.2 Ball Pythons
[1.0 '05 Orange Hypo (Specter)]
[0.1 '05 Het Orange Hypo (Sylvia)]
[0.1 '03 Normal (Sue)]
0.2 American Pit Bull Terriers (40lb darling lap dogs:Brandy&Mara)