The owner of every lot or parcel of land within the City upon which a tree, plant or shrubbery stands with any part thereof upon or overhanging a public street or sidewalk shall conform to the regulations herein provided.  Otherwise, the City shall cause such trees to be trimmed or cut down and removed in accordance with these regulations and assess the cost thereof against the owner of such lot or parcel of land.
   (a)   The owner shall trim or cause to be trimmed such tree, plant or shrubbery so that a clear height of nine feet between the lowest branch of the same and the street or sidewalk is maintained.
   (b)   The owner shall trim or remove, as the case may require, every dead, decayed or broken tree, plant or shrubbery, or part thereof, so that the same does not fall to the street, sidewalk, or abutting properties.
   (c)   The owner shall cut down or remove any tree, plant or shrubbery, or any part thereof, that may be necessary to provide a clear and unobstructed view of traffic from all directions at any street intersection, or abate any nuisance necessary to protect life, limb or property of persons, drivers of any vehicles or pedestrians using the street or sidewalk.