All trimming of shade trees shall be done to the satisfaction of the motor vehicle/highway division of the code enforcement department whose duty it shall be to enforce this chapter. Such department shall in all cases where the property owners shall neglect or refuse to trim their shade trees in accordance with Section 12.20.020 cause the same to be done after five days notice to such property owner or agent and charge the expense thereof to such property owner, and collect the same according to law. (Prior code § 31-4)