Trees and shrubs, growing upon, or near, the lot line, or upon public ground and interfering with the use, or construction of any public improvements shall be deemed an obstruction under this Article. Said roots may be removed by the Municipality at the expense of the owner of the property upon which the tree or shrub is located should the owner fail, or neglect, after notice, to do so. It shall be unlawful for any person, persons, firm, or corporation to obstruct, or encumber, by fences, gates, buildings, structures, or otherwise, any of the streets, alleys, or sidewalks. (Ref. 17-557.01 RS Neb.)