I added some polyfilla, rocks and sand (sealed with PVA for for durability).

Here's a close up.

For practicality the trees are removable during play and are attached to the bases with magnets. Here is a wood base with the trees removed.

And lastly here is a quick bones mini I knocked up for inclusion in our D&D party. He is playing the part of Aaron Tallbow in the Dragonlance Classics campaign I am running at the moment.

And in other news I have finally made a start on those ghouls I have been putting off for a while.