(1) Tree Planting: All tree planting shall be based on the city's "arboricultural standards and specifications guide" available from the city forester.
(2) Selection From List: All trees and shrubs shall be selected from the list provided in subsections 10-08-02(13), (14) and (15) of this chapter. Any deviations from this list must be approved by the Planning and Zoning staff. The appropriate class of trees and shrubs shall be chosen dependent upon the location of the plants (i.e., along streets or sidewalks, in parking lots, below overhead power lines, along utility easements).
(3) Prohibited Plant Material: Prohibited plant material shall include any that is considered poisonous, toxic or otherwise poses a nuisance.
(4) Substitution: Use of artificial plants or carpeting cannot substitute for landscape plant material. (Ord. 2661, 1-7-2008)
(5) Primary And Dominant Landscape Material: Primary and dominant landscape material shall be grass. A combination of materials such as bark, wood chips, stone, rock, gravel and lava rock is limited to twenty-five percent (25%) maximum coverage. Boulders and rock slabs cannot be placed in public rights-of-way. (Ord. 3156, 7-16-2018)
(6) Minimum Plant Sizes:
Evergreen trees | 6 to 7 foot height minimum |
Ornamental trees | 2 inch caliper minimum |
Shade trees | 2 inch caliper minimum |
Woody shrubs | 2 gallon pot minimum |
The minimum plant standards may be modified, with Planning and Zoning staff approval, based upon market conditions, size availability and/or other circumstances.
(7) Standards Met: All plant material installed pursuant to this article shall meet or exceed the minimum Federal standards as regulated by ANSI Z60.1, American standard for nursery stock.
(8) Placement Prohibited: The placement of plastic weed barrier under mulch is prohibited.
(9) Organic Mulch: Organic mulch, such as bark or soil aids, shall be applied to all planting areas for moisture retention, weed control and soil temperature moderation. (Ord. 2661, 1-7-2008)
(10) Protective Devices: Vertical curbing shall be provided around all planting areas that border driveways, parking lots and other vehicle use areas, including, but not limited to, street landscape buffers and interior landscape planter islands. The curbing shall be minimum six inch (6") vertical concrete curb and include a concrete gutter pan. (Ord. 3010, 11-16-2015)
(11) Wash Off: Facilities constructed for water and drainage purposes shall be designed so that no soil, bark, mulch or other similar materials shall be allowed to wash off the landscape area.
(12) Construction Within The Tree's Drip Line:
A. Impervious surfaces like sidewalks should be set back from the tree trunk equal to its diameter at maturity plus five feet (5'), with the exception of parking lot planting islands.
B. Grade changes greater than six inches (6") are prohibited within the drip line.
C. A simple fence or barrier that encloses the entire area beneath the tree canopy should be installed prior to commencing construction activity to reduce damage to a tree's root system. (Ord. 2661, 1-7-2008)
(13) Utilities:
A. Only Class 1 trees as identified in subsection 10-08-02(14) of this chapter may be planted below or within ten (10) lateral feet of any overhead utility wire.
B. All trees shall be planted outside of any underground utility easement unless written approval has been obtained from the easement holder.
C. Underground utilities installed by means of trenching shall be placed outside of any existing tree's drip line. Underground utilities installed by means of tunneling may be installed within the tree's drip line, provided the tunneling occurs a minimum of three feet (3') below existing grade.
D. Excavation in the soil within one foot (1') of the tree's roots is prohibited unless appropriate measures are taken to prevent the exposed soil from drying out.
E. Roots of a tree shall not be damaged by compacting or filling on or around the base of the tree.
F. If existing trees that are scheduled to be retained as part of the landscaping plan are severely damaged during the construction phase, they shall be replaced in accordance with section 10-08-02 of this chapter.
(14) Landscaping Around Signs:
A. The square footage of the landscaped area shall be equal to or in excess of the square footage of the sign.
B. Two (2) shrubs shall be installed on each side of the sign at a minimum.
C. The remaining area shall be completely covered with a mixture of vegetative or nonvegetative ground cover to include grass, flowers, mulch, vines, etc.
(15) Landscaping In And Around Riparian, Wetland, And Wildlife Areas:
A. Riparian, wetland, and wildlife areas in all developments and/or subdivisions shall be surveyed and determined. In written form, the appropriate agencies (i.e., Idaho Fish and Game and U.S. Army Corps of Engineers) shall confirm the results of the survey.
B. Stream crossings in riparian, wetland, and wildlife areas shall be constructed with design features that permit passage underneath of both aquatic and terrestrial species of fish and wildlife during all anticipated flow levels. There shall be no net loss of wildlife habitat.
C. All identified jurisdictional wetland areas shall be restored to a functioning condition, including planting with species appropriate to the site, and shall be maintained in a functioning condition. There shall be no net loss of wetland function.
D. A mitigation plan for any unavoidable impacts to fish and wildlife resulting from developments and/or subdivisions shall be developed and shall be incorporated into homeowners' or business owners' covenants. The following elements, at a minimum, shall be included in the mitigation plan:
1. Introduction/description of the property and surrounding area. This shall include a description of the existing natural resource values present, wildlife commonly found in and near the project and habitat types. Included shall be estimates of the quantity and quality of the various habitats found on the property as well as mapping of existing vegetation (habitat). Aquatic species and habitat should be included if streams are present. It should also include the scope of the mitigation plan (i.e., if it covers the entire project or just a particular phase). In the case of projects in high value wildlife habitat, and to provide objective and measurable preproject wildlife values, a habitat evaluation procedure should be conducted for key species. Include goals and objectives of the mitigation.
2. Assessment of potential impacts. This shall include anticipated impacts, both direct and indirect, resulting from the development.
3. Proposed actions to avoid, reduce, compensate for, and mitigate impacts. Include on site and off site mitigation necessary to achieve no net loss of wildlife values.
4. Description of net impacts after mitigation is implemented. Include a description of unavoidable impacts and those impacts that have been minimized.
5. Time line for implementing all mitigation actions.
6. Monitoring to ensure effectiveness of mitigation actions and long term operations and maintenance to ensure mitigation lasts in perpetuity. There shall be actions described in the plan that ensure that mitigation actions are permanent (e.g., easements) and continue in perpetuity (e.g., habitat improvement). Recourse for failed mitigation efforts should be identified.
E. Approval letters, regarding mitigation plans for riparian, wetland and wildlife areas, from all stakeholder agencies shall be obtained and submitted to the Planning and Zoning Department prior to approval of any construction drawings. (Ord. 3156, 7-16-2018)