I have tried all the above even put mouse traps in the area she was digging. Come to think of it I haven't seen those traps for 2 years!! I usually don't catch her doing it, but when I do she gets a butt slap and stern NO!!
I have heard of people who have the money making their dog a sandbox, so they can dig there, its good for their nails too, Or taking the pen they may be in and filling it with sand so they dig there.
Good luck


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~~~"Noone appreciates the very special
genius of your conversation as a dog does."
Christopher Morley