Grading around existing vegetation to be preserved on site shall be outside the critical root zone, unless otherwise approved by the Design Review Board. The critical root zone may be defined as a radius equal to one foot for each inch of caliper measured one foot above the natural grade, or as defined by a qualified arborist or landscape architect. A tree preservation plan developed by a qualified arborist may be required by the Administrator.
(Ord. 27(2007) § 4)