(a) All grass areas and yards on improved property shall be properly maintained in a neat and attractive manner and kept free of dead plants, refuse, debris and shall be maintained further in a manner such that grass, weeds and other rank vegetation shall not exceed six inches in height.

(b) All unimproved property in the city shall be maintained in a manner such that weeds and rank vegetation shall not exceed 12 inches in height provided, however, that with respect to property or portions of property containing wild lands in their native state, not previously cleared, such as a natural hammock, this height limitation shall apply only to the first 15 feet of such lands abutting a public street or right-of-way, unless such lands constitute an approved buffer zone under the code of the city.