The thread used for modeling should be removed, otherwise it will be pulled into the branch as it thickens, causing permanent damage to the branch.

We know that the thickening of trees is caused by the division of cambium. After the branches are processed and shaped, they will be continuously thickened on the basis of modeling, so the removal time should be after the branches have had at least one successful growth process, so that the new part can fix the original iron wire, and the forced form of the iron wire will be fixed again after removal.