When it comes to development in areas with steep slopes or other difficult terrain features, there are a number of special considerations that must be taken into account. From health and safety to environmental concerns, and even aesthetics, it is important to plan carefully when working in rugged areas. Municipalities often use zoning regulations to limit the disturbance of steep slopes in order to prevent erosion, reduce the risk of dangerous landslides, and preserve picturesque hillsides. When it comes to tree services in these areas, there are a number of rules and regulations that must be followed. For example, large trees must be planted at the rate of one tree with a caliber of three inches per 500 square feet of land area of vegetation removed.
Alternatively, small trees must be planted at the rate of one eight-foot tall tree per 100 square feet of lot area of vegetation removed. The minimum size for a tree planted for restoration is a 12-foot tall evergreen tree and a three-inch caliber deciduous tree. A tree protection plan is also necessary when working in these areas. This plan modifies the undisturbed area around a tree proposed for conservation and protects the tree during construction. Tree protection signs should be attached to the fence that reads “TREE PROTECTION FENCE: no alteration of the ground, parking, storage, dumping or burning materials are allowed inside the tree protection fence”.
In some cases, a tree replacement fee may be used, which is entered into the city's urban forestry account. In addition, no tree of a caliber of six inches or more should be felled and the critical root zone of that tree must be an undisturbed area in any zoning lot. The Urban Planning Commission may authorize modifications to the provisions of sections 105-31 (Botanical Environment and Tree Preservation Requirements), 105-32 (Botanical Environment and Tree Planting Requirements) and paragraph (b) (of section 105-35 (Level II Requirements for Private Entrances and Roads). In the case of densely forested sites, the director may allow a tree study sample to be submitted that can be applied to the forested parts of a site in order to meet the tree study requirement. Finally, all site developments, expansions, and alterations must comply with the tree planting requirements set out in this Section, whether or not existing trees are removed as a result of such development, expansion, or alteration of the site. A preparation area is any area of a zoning lot used during the construction of a development, expansion, or alteration of the site for the purpose of accumulating land or construction materials; storing, cleaning, or repairing equipment, vehicles, or construction tools; or storing leachable construction products, gases, or other materials used to clean or repair vehicles, equipment, or tools.