For some artists, each individual type of tree is symbolic in its own right, such as oak trees being used to express courage and power while the ash tree is used for interpretations of sensitivity, spirituality, and a higher state of being.
Contemporary framed tree art varies considerably and the way that it's depicted changes its purpose. Flat artwork containing this subject matter is typically used symbolically in order to express some mythical aspect of trees. One example of this form of symbolism is in Gustav Klimt's work 'The Tree of Life'. This painting is created out of vibrant colors and the depictions of twisting, weaving branches suggest the various paths that life can take as well as the mental and spiritual growth that every person has to undertake in their lives.
Representational styles, on the other hand, portray contemporary tree art in a different way that is no less emotive or symbolic in execution. William Blake's famous work, 'Birch Haven' is an example of this artistic treatment. Birches, with their white bark and upright forms, serve to symbolize new beginnings and cleansing from past events. This is clearly seen in Blake's work where the white, vertical forms of the birch trees separate the viewer from the shadowy chaos of the forest beyond them, barring them from entry into the darker realms of regret and self-doubt.
Throughout the history of art, no subject has received, or deserved, as much attention from artists and their audience as tree artwork has.