There are two different plants at the bottom, but their names elude me. They're the plants sold at nurseries to plant between stepping stones. I'll have to see if I still have the tags somewhere. The "cork bark" is actually a piece of branch I found in the woods while looking for caudates. There is a myriad of things growing on it (bracket fungi, lichens, ect.). The bare area in the center is actually holes made by a woodpecker or flicker. I've seen quite a few animals (tiny slugs,land snails, insects) appear over the week that probably came from it.