I agree with you on the idea of giving them a spot to dig. For some reason, I just don't think that would really work (although one of my labby friends swears it works). I heard about putting some of their poop in the hole and covering it back up with dirt. In theory, the dog would be disgusted by digging in its own poop. I don't know of anyone who has tried it, but it may be worth a shot. Good luck!
Bridget and Summer
Bridget and Summer