(a) All side and rear yards in this District abutting residentially-zoned land shall be screened therefrom and shall be required to have effective screening suitable for the purpose intended and as required in this section. Such screening shall be esthetically attractive, compatible with the surrounding residentially-zoned properties, and have year-round screening value. Deciduous trees and shrubs are not acceptable for screening purposes. Acceptable for such screening purposes are plantings of spruce, pine, fir or hemlock in sizes sufficient to provide effective screening at the time of planting. Arborvitae (thuja) is not acceptable for permanent screen planting. Plantings shall be so arranged as to provide both effective screening immediately, and yet provide adequate space for development at maturity. Where plant material is used, a growing strip at least six feet in width, measured perpendicular to the lot line, shall be provided. The surface of the growing strip may not be paved or covered over with any material impervious to the free passage of either air or water. Also acceptable for' screening purposes are walls or fences constructed of wood products, brick, stone or precast concrete shapes other than blocks.
(b) The above requirements for screening shall be in addition to any applicable requirements of Chapters 1157
and 1159
, pursuant to Section 1131.06 for screening, and should any screening be required by two or more provisions of this Zoning Ordinance, the most restrictive requirement shall control.