(A)   All open areas of a lot which are not used or improved for required parking areas, drives or storage shall be landscaped with a combination of overstory trees, understory trees, shrubs, flowers and ground cover materials.
   (B)   All new landscape trees and shrubs must meet the American Standard for Nursery Stock and American National Standard relating to planting guidelines, quality of stock and appropriate sizing of the root ball. Landscape trees must be balled and burlapped or moved from the growing site by tree spade. Deciduous trees will be not less than one and one quarter inches but not more than three inches caliper for balled and burlapped trees, and not less than three inches but not more than six inches caliper for spade-moved trees. Coniferous trees will not be less than six feet in height but no more than eight feet for balled and burlapped trees, and not less than eight feet in height but not more than fourteen feet for spade-moved coniferous trees. The city may allow larger balled and burlapped or spade moved trees if these trees are accompanied with a three year guarantee.
   (C)   All lot areas not covered by buildings, sidewalks, parking lots, driveways, patios or similar hard surface materials shall be covered with sod or an equivalent ground cover approved by the city. This requirement shall not apply to site areas retained in a natural state.