In finding it's way through the wood, the electrical energy forms a fractal pattern that burns into the surface.
The Monkey Buddha Archives:
This is an example of a Lichtenberg figure, typified by the fractal-like branching.
The resemblance to the shape of trees gives insight into the influence of energy on the appearance of form.
The pathways are trying to connect to the opposite pole. In the same way, energy pathways that make up he shape of trees, and all energetic systems, are configured by the imperative to transfer energy as efficiently as possible and connect interactively with the environment.