§ 13-106. Required landscaping materials

(a) All required landscaped areas, including landscaped areas within parking lots, shall consist of drought tolerant plant material and shall meet the following minimum requirements:

(1) Tree count: One (1) tree (fifteen-gallon or larger) shall be provided for every two hundred (200) square feet of landscaped area. Fifty (50) percent of all trees shall be evergreen. Twenty-five (25) percent of the required trees shall be twenty-four-inch box or larger. Canopy trees for parking lot areas shall be included in the tree calculation. Canopy trees shall be installed throughout parking lot areas at the ratio of one (1) tree per six (6) parking spaces, with an average of thirty-six (36) square feet of planter area provided per tree. Upon written request, the number of required trees may be reduced by the planning division when it is determined that an alternative design will meet the intent of section 13-104, landscape plan objectives.

a. Tree count exception: One (1) tree (minimum twenty-four-inch box or larger) shall be provided for every three hundred (300) square feet of landscaped area for automobile dealerships.

(2) Tree selection: Trees shall be selected based on their suitability and sustainability in tree wells, narrow planters, and medians. Trees shall also be selected on the basis of quality and diversity as indicated below:

a. Twenty-four-inch box trees shall be a minimum 8 feet in height as measured from top of soil line in the box, and shall have a caliper of approximately three (3) inches in diameter, eighteen (18) inches above the top of the root ball, or meeting with approval by the planning division. Selected trees shall be healthy, vigorous, and free from plant disease and insect pests. Selected trees shall be symmetrical and typical for variety and species. All trees shall have a normal and healthy root system free from being root bound. Fifteen-gallon trees recently transplanted into twenty-four-inch box, and twenty-four-inch box recently transplanted into thirty-six-inch box, and so forth, shall not be substituted for the required tree size.

b. Trees shall be selected from either the city's recommended street tree palette (appendix B) or private property tree palette (appendix D), included in the streetscape and median development standards. Trees not selected from these sources shall be approved or disapproved by the planning division based on the objectives in this chapter.

c. All trees shall be staked in accordance with standards contained in the streetscape and median development standards.

d. At least two (2) different tree species shall be identified on plans and installed as part of the project landscaping.

e. Palm trees shall not be used in the landscaped street setback, except as an accent plant to highlight main driveway entrances, to accessorize the front of a building, or for unique or theme uses. Two (2) palms shall constitute one tree in the ratio of required trees for required landscape areas. Palm trees shall not be used as a parking lot tree.

(3) Shrub count: One shrub shall be provided for every twenty-five (25) square feet of open space. Sixty (60) per cent of the required shrubs shall be a minimum of five (5) gallons. Upon written request, the number of required shrubs may be reduced by the planning division when it is determined that an alternative design will meet the objectives in this chapter.

(4) Groundcover: At least seventy (70) per cent of all landscaped areas containing trees and shrubs shall be under planted with groundcover, with the remaining areas to incorporate a minimum two-inch layer of uncontaminated compost or mulch. Decorative (commercial) bark is not acceptable. Groundcover shall be planted in a triangular-spaced pattern to ensure one hundred (100) percent coverage within one (1) year of planting. A minimum two-foot diameter clearance, measured from each tree trunk, shall be maintained free of groundcover or turf. Uncontaminated shredded mulch or compost shall be applied and maintained in these areas.

(5) Turf: Turf incorporated into the landscape design shall not exceed fifty (50) per cent of the total landscaping area. All turf shall be of a drought tolerant variety. Redwood headerboard, or other material acceptable by the planning division, shall be installed to separate turf from planter and groundcover areas.

(6) Water conservation: For projects that are subject to water efficient landscape guidelines, landscape and irrigation plans shall meet all the specified requirements.

(b) Street trees located within the public parkway, or any public right-of-way, shall be approved by the public services department.

(c) The plant material selected shall be suitable for the given soil and climate conditions. Plant selection shall take into consideration water conservation through appropriate use, and groupings of plants that are well adapted to particular sites and to particular watering needs, climatic, geological or topographical conditions.

(d) Materials such as crushed rock, redwood chips, pebbles and stone are not satisfactory substitutes for live plant materials although their limited use may be approved by the planning division. Uncontaminated mulch, shredded bark, or compost may be used to fulfill part of the groundcover requirement as noted in section 13-106(a). Uncontaminated mulch, shredded bark, and/or compost used as a groundcover shall maintain a consistent two-inch minimum layer and provide complete coverage under shrubs and trees.

(e) Artificial plants are prohibited.

(Ord. No. 97-11, § 2, 5-5-97; Ord. No. 99-13, § 2, 9-20-99; Ord. No. 10-2, § 3e., 2-2-10 )