Cut them back as much as you can, then dig around the root ball to loosen it. You may be able to drag it out. Were you going to attach it to the trailer hitch? That might work. I guess you don't know anyone with a mini-backhoe you could borrow, huh?
No - wish we did... I'd be sucking up to that person a lot... we could use a mini backhoe for a few jobs around here :~)