Eugene van der Pijll
The wood on the joinery is considered to be in your possession?
The wood on the forester (and the Copse) is not considered to be in your supply during the game for the Store Clerk, but at the end of the game, it is counted for the Joinery (and Sawmill). Compare with grain on fields: during the game, you can't do anything with it, but at the end of the game, it counts for victory points.
At least, that is my interpretation.