I did a simple height test in UDK. It is smart to check the scale of your player to the 'tree stump' and this enabled me then to sculpt with out worry.
From this I created a simple tree-stump in 3DS Max enabling me to then export this in to ZBrush for which this base mesh can be sculpted on top and add in the details.
This is the base mesh that is now imported into ZBrush, with the default brick red texture. Imported with no problems to the mesh.
Here presented development stages of my tree stump progress. Although, I have used ZBrush previously this was the first time I have actually sculpted an organic shape. The concept here was to try to convey the age of the tree stump by showing how with age the bark appears to thickens with it's own 'wrinkles'.
The image above is my first finish attempt. I was trying to incorporate different states that tree bark may be presented as within a tree stump that has been standing for sometime for example, the erosion of the bark that has fall off the stump leaving the raw under-side of the tree it self. I had some difficulty in achieving this mainly due to the fact that it has been sometime since I have used the program, so needed to refresh my skills using trial and error method of working it out.