Subject to the provision of § 909.02 of first giving notice to an offending property owner, the City Engineer shall have the right to trim or remove such trees and shrubs within the lines of all streets, alleys, lands and public grounds as may be necessary to insure safety to pedestrians and vehicular traffic and, under the power herein given, he may remove, cause or order to be removed, any tree, shrub or part thereof which is in an unsafe condition or which, by reason of its location, may be hazardous to pedestrians or vehicular traffic. The City Engineer shall have the power to enter upon any private grounds for the purpose of trimming or removing trees and shrubbery in order to prevent danger therefrom to person or property, in the event the owner or occupant of such premises does not comply with the City Engineer's orders relative to the trimming or removal of trees or shrubbery which, in his opinion, are hazardous to pedestrians or vehicular traffic.
('71 Code, § 909.05)