Ditto what Kimber said. And she does mean EVERYTHING! You will have bare dirt in a matter of weeks. Then it gets really fun when it rains...
Ahh... the joys of monster sized tortoises. I wouldn't trade my three sulcatas for a whole herd of radiateds.
... don't misunderstand. I'd like to have a herd of radiateds. A lot. I just wouldn't trade MY three biggun's for them. I might go buy three sulcatas to trade for them though... oh never mind.
Now I don't do that with mine as the grass and weeds grow faster than my torts can keep up with. So this is another point... The more room your yard has, the less likely your tort will be able to eat it down to roots. And if you have healthy grass cover all year, then mud won't become an issue.
So more space and decent, healthy soil means you have less to worry about. Smaller spaces mean you will either let them graze it to the ground and then be stuck with muddy and unhealthy soil that will no longer support good grass growth and grazing, or you need to work out a managment approach where you move the tort from one small pen to another to allow the grass to be eaten down, fertalized, but then left to grow back while you move the pen to another spot. More work, but then you have less to spend on suplimental food and your yard will be healthier.
With mine, I've realized I need to either start mowing it a few times in the spring and early summer, or bring in my goats to have them knock it down. Otherwise it grows too high and is then less productive (you want to maintain the healthy fresh growth as much as possible).
Anyway, I'm rambling, but hopefully you get the point