He cited examples such as Vienna, where a referendum was held to stop a downtown university from cutting down six trees, and Hawaii, the first place in the US to legislate to protect its urban foliage by passing a law that required permission to cut or move any tree over eight feet tall, whether in a private garden or a public park.
為了不允許七株大樹被砍，維也納曾經用公民投票否決了一座位於市中心的農工大學；夏威夷則是美國第一個立法保護城市樹木的地方，依夏威夷州單行法的規定，舉凡高度超過八英尺的樹，不管在私人庭園或公園中，要砍要移，都得先申請許可......。