All trees planted in any street or parking shall be plated a distance from the curbs or curb lines and sidewalks in accordance with the tree species size class listed under Section 151.04, and no trees may be planted closer to any sidewalk than the following: small trees, two feet from the sidewalk; medium trees, three feet from the sidewalk; large trees, four feet from the sidewalk. Notwithstanding any provision to the contrary, no tree shall be planted where the width of the parking is less than four feet.