A clear vision area shall be maintained on the corners of all property adjacent to the intersection of two streets or of a street and a railroad. A clear vision shall contain no planting, fence, or other temporary or permanent obstruction exceeding two and one-half feet in height, measured from the top of the curb or, where no curb exists, from the established centerline grade of the street. Taller trees may be permitted if all branches and foliage to a height of eight feet above the top of the curb are removed. (Ord. 295-N, §6, 2003)