if you take a visit to your local aquarium centre you will find a selection of resin stumps that could be the centre of an amazing miniature scene. There are dozens of wonderful shaped pieces to choose from.
They are made of a resin material but they are very well produced and the colours are perfect. You could even paint them to suit your needs if you would like to add a bit of moss to them. You can also cover them in actual moss or lichen, with ‘ferns’ growing around the base.