Arborsculpture is one name for an art that people have been practicing since trees have been consiously cultivated.

Bonsai is probably the most extreme form of tree "art" or arborsculpting......

The tree's top foliage is pruned to restrict growth, the branches are wired into desired directions and the roots are kept confined and pruned to restrict growth. There are bonsai trees that have lived long enough to be passed from one generation of caretakers to another.

Espalier, Fans and Cordons are methods often used with fruit trees......

A fruit tree's branches are trained to grow horizontialy or at a wide angle. In a cordon the entire tree is planted at a 45 degree angle. The trees will be easier to care for, the fruit can be picked without a ladder, and a tree will begin bearing fruit at a much younger age. Trees are espaliered flat against a walls, fences or trellises. Being against a sunny wall can give a tree needed winter protection and extra warmth in the summer. Living fences are a common ornamental use of espalier.

Pleaching is when trees are entwined with their neighbors and trained into a pattern or shape, such as a wall or tunnel......

Sometimes the trees are encouraged to graft to each other, by abrading their respective barks and tying them together. A form of this type of training is what is used in most modern arborsculpture.

There are some people who feel all this manipulation of living enities, that if left to grow on their own in a perfect enviroment can be so magnificent and beautiful, is unnatural, or even wrong.....

I find myself responding to the entire scale on this issue....one of the great joys of my life is discovering, marveling and cherishing wild trees that have reached maturity, especially the few special ones that have surpassed even others of their species in age, girth or awesomeness. But I also act out of the ancient human urge to see how far I can manipulate the plants in my enviroment. Working with the energy of trees is particularly exciting because they are large and undeniably living beings. If you do not respect the tree's natural processes you will not be able to create anything. And truly, you are not really creating anything, only encouraging and directing growth....