A tanuki in bonsai is a technique that involves using a dead piece of wood and a living plant to create the illusion of an old and mature tree. The word tanuki means raccoon dog in Japanese, and it is also a mythical creature that is known for its shape-shifting abilities. The tanuki in bonsai is named after this animal because it deceives the viewer into thinking that the dead wood is part of the living plant. The tanuki in bonsai is considered a controversial and unethical practice by some bonsai enthusiasts, who argue that it goes against the principles of natural beauty and harmony. Others see it as a creative and artistic expression that showcases the skill and ingenuity of the bonsai artist.