Spaces between branches and around the trunk are very important design tools
What do these open spaces achieve in bonsai design? Each bonsai is characterised by two dominant empty spaces:
Internal Primary Space is defined by the ground surface, the edge of the trunk that follows the movement of the tree and the extending branch, which gives this movement.
External Secondary Space is the opposite; it is always against the movement of the tree. These spaces are sometimes big, sometimes not. The interior space can be the larger, sometimes it is not.
To define the movement of the tree remember that it must be in agreement with the slope of the trunk, the direction of the apex, and that of the extending branch. You can see in the diagram (right) what that can do. The principal open space is on the left because the movement of the tree is on the left. Indeed the apex moves towards the left, as does the trunk and the large extending branch. But what is interesting is that there are many small subdivisions of space to the main and secondary spaces. These small irregular spaces give life to the tree.
All open spaces that offer symmetry and repetition must be avoided. Others are acceptable and necessary. Note that the most beautiful open spaces can be found in rugged trees, as you can see in some of the examples shown here. One seeks the open space principal on conifers. Apply this principal to your trees — seek out these open spaces and you will find them.
Some examples
