rubber mulch rings for J. maples?
I bought three nice J. maples this past spring and got some of those crushed rubber mulch rings to go with them. I stopped using them as they were harboring sow bugs/pill bugs when it was warm. Now that it is cold, I'm thinking of putting them back. But first I thought I would seek out opinions on them. Do they work? Do they cause any problems? Should I just use oak leaves for mulch? I have the things so I kind of hate to waste them. thanks