How interesting! Have you tried unpotting a targeted plant to inspect the roots and see if there are any additional signs?

However, a 3/4 inch hole sounds like the right size for mice. Perhaps baby mice...?

Baby mice, that is a possibility. This is the first winter this has happened and I guess I have a feeling it is an adult rodent of some kind. I had thought of your idea of emptying a pot and seeing the damage. I surely would wear vinyl gloves for that!

Thanks for your thoughts .

Another thought would be a shrew. Trying to find on the internet what would want to dig down into a pot. It would probably be looking for roots to eat or bugs and worms. I think shrews can be pretty fierce. I'm not really afraid of mice and such but don't like to be startled when they run out