(A) Landscaping guidelines. The purpose of the guidelines and technical requirements is to encourage plant longevity, minimize maintenance, and mitigate conflicts with other site features. An initial investment in high quality materials, careful design and planning, and proper construction techniques can result in plant longevity and long term maintenance cost reduction.
(1) Species selection. Appropriate species selection is critical to maximize the benefits of plant materials. Healthy, long lived plants well suited to a site will reduce maintenance and replacement costs, while providing the most aesthetic and environmental gain. Native species in the built environment will supplement and connect the existing natural areas. Diversity is also important for an overall healthy and balanced landscape that is less susceptible to pests and disease.
(2) The city shall maintain a list of approved species which species acceptable trees within the size categories reference in this section. Approved species are classified by size. For each site, plants shall be selected based on mature size and adaptability to site conditions, such as microclimate, salt, pollution and other factors. The list of approved species is not exhaustive. Applicants requesting to plant a species not on the list shall submit species name, height, width, form, hardiness zone, and other relevant information. The city shall classify new species based on tree size standards. For large projects the city may require applicants to comply with the following requirements:
(a) Species diversity;
(b) A minimum percentage of native species;
(c) A minimum percentage of large trees;
(d) A minimum percentage of evergreen streets.
(3) Prohibitive species. The following trees/plants are prohibited due their high maintenance costs, surface roots, intolerance to storms, undesirable fruiting habits, or a susceptibility to disease or pests: all species of North American Ash, Cottonwood, Lomardy Poplar, Box Elder, American Elm, and Siberian Elm, Amur Maple, Common Buckthorn, Barberry, Burning Bush, Russian Honeysuckle, Japanese Spirea. The minimum plant size requirements are described in the following table:
Table 152.374.01C Minimum Plant Size Requirements
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Plant Type | Minimum Size* |
Table 152.374.01C Minimum Plant Size Requirements
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Plant Type | Minimum Size* |
Large trees | Bare root - 1.75" Balled and burlapped or container - 2" caliper |
Medium and small trees | Bare root - 1.5" Balled and burlapped or container - 1.5" caliper |
Evergreen trees | 6' height |
Large shrubs | 5 gallon container |
Medium shrubs, small shrubs and groundcovers | 3 gallon container |
Ornamental grasses and perennials | 4" pot |
* City may limit bare root plantings in areas of high visibility. In selected situations the City may allow ten whip bare root plantings, or five 3/4" caliper bare root plantings to be substituted for 1 large tree. Bare root plantings must be protected with rodent guards. | |
a. All boulevard trees shall be balled and burlapped and a minimum size of 2" caliper. | |
(C) Quality credits. Existing healthy trees that are not susceptible to disease, new larger or smaller sized trees, or decorative landscaping may be credited toward the required trees detailed in this section, and the additional trees required for screening as defined in § 152.375. The following table establishes the landscaping credits.
Figure 152.374.03 Credits
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Vegetation Type | Size | Exchange Credit |
Figure 152.374.03 Credits
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Vegetation Type | Size | Exchange Credit |
Existing Trees | 2” bb (Caliper) Deciduous or between 6' and 14' Coniferous | 1 tree |
4” bb (Caliper) Deciduous or 14' Coniferous or larger | 2 trees | |
New larger trees | 4" bb (Caliper) or 14' Coniferous | 2 trees |
Two 3" bb (Caliper) | three 2" trees | |
Ornamental Deciduous Trees or smaller overstory deciduous | min.1.5" (Caliper) | 2 trees may be substituted for 1 overstory deciduous tree (maximum substitution = 50% of required overstory trees ) |
Shrubs | 10 large shrubs | 1 tree |
Decorative Landscape Yard | Exterior sculptures, fountains, decorative walks, courtyards and/or additional ponds beyond those required, shown on a landscape plan that meets the intent of this section to the satisfaction of the City Manager and/or City Council | |
(D) Energy conservation. Plant material placement should be designed to reduce the energy consumption needs of the development.
(1) Deciduous trees should be placed on the south and west sides of buildings to provide shade from the summer sun.
(2) Evergreens and other plant materials should be concentrated on the north and west sides of buildings to dissipate the effect of winter winds.
(E) Sustainable landscaping requirements. The city encourages the use of special design features such as Xeriscaping; rain gardens/bioretention systems; landscaping with native species; green rooftops; heat island reduction; and aesthetic design. All new development and redevelopment must include two of the following choices in subsections (1) through (3) below or a green roof:
(1) Xeriscaping. Xeriscaping is landscaping which uses plants that have low water requirements, making them able to withstand extended periods of drought. Xeriscaping landscapes are a conscious attempt to develop plantings which are compatible with the environment and make a conscious effort to minimize use of water. A minimum of 20% of the total required landscaping vegetation shall be of low water requirement types.
(2) Rain gardens/bioretention systems. Bioretention systems can be described as shallow, landscaped depressions commonly located in parking lot islands or within areas that receive stormwater runoff. For credit under this section, the rain garden/bioretention system shall be aboveground and a visible part of the green or landscaped area. Stormwater flows into the bioretention area, ponds on the surface, and gradually infiltrates into the soil bed. Pollutants are removed by a number of processes including absorption, filtration, volatilization, ion exchange, and decomposition. Filtered runoff can either be allowed to infiltrate into the surrounding soil (functioning as an infiltration basin or rainwater garden), or discharged to the storm sewer or directly to receiving waters (functioning like a surface filter). The use of under drain systems are discouraged unless where infiltration is prohibited by the water resources management plan. Runoff from larger storms is generally diverted past the area to the storm drain system.
(3) Landscaping with native species. Fifty percent of the plantings used in the landscape plan shall be of native plant communities of Brooklyn Park on file with the city and approved by the City Planner. These plant communities include:
(4) Green rooftops. Green rooftops are veneers of living vegetation installed atop buildings, from small garages to large industrial structures. Green rooftops help manage stormwater by mimicking a variety of hydrologic processes normally associated with open space. Plants capture rainwater on their foliage and absorb it in their root zone, encouraging evapotranspiration and preventing much stormwater from ever entering runoff streams. What water does leave the roof is slowed and kept cooler, a benefit for downstream water bodies. Green roofs are especially effective in controlling intense, short duration storms and have been shown to reduce cumulative annual runoff by 50% in temperate climates. A minimum of 50% of the total roof area shall be planted material. Living vegetation must cover 90% of the surface of the green roof area.
(E) Aesthetic design. Sites shall be designed to include two of the following: public art, fountains, plazas, perennial beds, landscaping at entry of the site, or other amenities reviewed and approved by the City Planner.
(G) Utility interference. Overstory and coniferous trees may not be installed underneath overhead utility lines nor may any landscape materials be installed over utility lines except in compliance with the City Code and city policy.
(Ord. 2000-936; Am. Ord. 2001-952, passed 5-14-01; Am. Ord. 2003-989, passed 2-10-03; Am. Ord. 2003-997, passed 5-12-03; Am. Ord. 2006-1059, passed 6-5-06; Am. Ord. 2008-1085, passed 3-24-08; Am. Ord. 2012-1133, passed 3-5-12)