What creature living in this area has a four foot hairy tail and burrows?
"Detachable" in terms of tails is sort of a misnomer. There aren't many animals - particularly hairy ones, that would gladly give up their tails.
When I pulled it out, it was about 6 inches into the ground, so I'm guessing that whatever it was, it either didn't make it to where it was trying to go or it had a detachable tail. The rest of the tail was flat across the ground, so it was probably there for a while. I just never noticed it.