Bonsai wire is a special type of wire that is used to shape and train bonsai trees. It can be made of annealed copper or anodized aluminum, and it comes in different sizes or gauges depending on the thickness of the branches to be wired. Bonsai wire is wrapped around the trunk and branches of a bonsai tree in a spiral pattern, and then the branches are bent to create the desired shape and style. Bonsai wire is usually removed after a few months, when the branches have set in their new position. Bonsai wire is an essential technique for turning a bonsai tree into a work of art.