The location of existing natural features, including but not limited to natural drainage swales, watercourses, wooded areas and wetlands, as defined by the New York State Department of Environmental Conservation and the Board of Trustees of Southold Town, marshes, ponds, dunes, bluffs, beaches, kettleholes, escarpments, wildlife habitats, flood hazard areas, erosion-prone areas and trees of six inches in diameter at a point three feet above the trunk base.