All buffer zones shall include a dense screen planting of trees, shrubs, or other materials, or both, as approved by the Planning Board, the full length of the lot line to serve as a barrier to visibility, air borne particles, glare and noise. Such screen planting shall be located within the exterior 10 feet of the buffer zone, and shall be in accordance with the following requirements:
1. Plant materials used in the screen planting shall be at least four feet in height when planted, be of such species as will produce a complete visual screen of at least six feet in height when mature, and be of nursery stock, free of insects and disease.
2. The screen planting shall be maintained permanently and any plant material which does not live shall be replaced within one year or one growing season.
3. The screen planting shall be so placed that at maturity it will be no closer than three feet to any street or property line.
4. In accordance with the provisions of subsection
26-23.6a (Storage and Waste Disposal), a clear sight triangle shall be maintained at all street intersections and at all points where private accessways intersect public streets.
5. The screen planting shall be broken only at points of vehicular or pedestrian access.