Bev, no soil loss! Of course in the beginning the soil came to the edge and there was loss. But after four years it is stabilized and you can see that the moss helps a lot! One really wants to have some wood showing around the edge to show that it really is a table. At one time I thought of adding more soil but I like the look as it is.
On the back side there is some "hangage" of plants over the edge, covering the wood. I wonder how long I can get it to grow over the edge...