A.   All landscaping materials shall aesthetically enhance and be environmentally compatible with the site area. The landscaping shall be installed to enhance the view of the property from the public streets(s) adjoining the property. Insofar as is practical, the trees used shall represent a mixture of deciduous and coniferous varieties. Existing trees and shrubs may be incorporated into a landscaped area as long as they are healthy and in good condition and do not conflict with plant location requirements of this chapter (such as in parking areas).
   B.   The minimum portion of the site area to be landscaped, as defined in this section, shall be as follows:
      1.   Residential districts (R-1 through R-7 inclusive): Twenty percent (20%) of the site area for all permitted uses with or without a special use permit, except single-family and two-family dwellings;
      2.   Public facilities district: As determined by the planning commission;
      3.   Limited commercial district (C-1): Twenty percent (20%);
      4.   General commercial district (C-2): Fifteen percent (15%);
      5.   Industrial district: Six percent (6%) which shall include landscaping strips along major street frontages. These landscaping strips shall be no less than ten feet (10') in width regardless of the percentage of the site area involved;
      6.   Street medians: One hundred percent (100%). Xeriscape is encouraged for medians.
   C.   The minimum number of trees to be planted in the required landscape area shall be one tree per three hundred (300) square feet in residential zoning districts and one tree per five hundred (500) square feet in other zoning districts. Parking lot trees per subsection H of this section are in addition to this requirement.
   D.   Evergreen trees shall be a minimum of six feet (6') in height at time of planting. Fifty percent (50%) of deciduous trees shall be a minimum caliper of one inch (1") at time of planting and fifty percent (50%) shall be a minimum caliper of two inches (2") at time of planting.
   E.   Sixty percent (60%) of container grown shrubs and plants (excluding trees), and excluding those plants grown in flats, shall be minimum five (5) gallon size at time of planting, and the remainder shall be minimum one gallon size at time of planting.
   F.   The latest edition of the "American Standard For Nursery Stock" by the American Association of Nurserymen shall be the criterion for sizes and grades of plant materials.
   G.   Use of turf:
      1.   The minimum dimension of each lawn or turf area shall be eight feet (8').
      2.   The maximum slope of lawn or turf area shall be four to one (4:1).
      3.   Turf may not constitute more than fifty percent (50%) of the required landscape area.
   H.   Parking area landscaping is in addition to other required landscaping. The parking area shall be subject to the following minimum standards:
      1.   Each planter island containing a tree shall have a minimum area of three hundred (300) square feet for double loaded parking and one hundred fifty (150) square feet for single loaded parking, with a nine foot (9') minimum interior width.
      2.   At least one shade tree shall be planted for each seven (7) parking spaces for parking lots under one hundred twenty five (125) spaces in size; for those over one hundred twenty five (125) spaces, at least one shade tree shall be planted for each ten (10) parking spaces.
      3.   Shade trees shall be planted in such a manner as to provide the maximum amount of shading in the parking area. A maximum of fifty percent (50%) of the trees shall be allowed in the perimeter of the parking area.
      4.   All areas utilized for landscaping shall be surrounded by curbing at least six inches (6") in height and four inches (4") in width, and shall be constructed of reinforced concrete, masonry, treated railroad ties, or other material acceptable to the public works director.
      5.   Landscaping strips, a minimum of ten feet (10') in width (except as otherwise specified in this title) shall be provided along public street frontages and of the total required trees, one tree shall be planted in the landscaping strips for each twenty five feet (25') of street frontage. This requirement is not in addition to the number of trees required in the parking area.
   I.   Ground covering shall be provided over the entire landscape area to prevent erosion, inhibit weed growth, and to present an aesthetically pleasing appearance. Ground covering may include:
      1.   Living plants, such as shrubs, turf grasses, vines, meadow grasses and wildflowers, or other living ground covers.
      2.   Wood chips, bark, decorative rock, or other nonliving materials may also be used.
      3.   Nonliving materials may not be used for more than ten percent (10%) of the total landscaped area and excludes the areas of temporary coverage allowed for all plant and ground cover maturity. Plastic, steel, or other appropriate edging material shall be provided around ground cover beds to retain loose ground cover material.
      4.   If approved by the city council, Xeriscape may be used for up to ninety percent (90%) of the total landscaped area.
   J.   Soil in planted areas shall be loosened to a minimum depth of eight inches (8") and improved by incorporating a minimum of two inches (2") of organic soil amendment into the top six inches (6") of soil prior to planting.
   K.   Planted areas shall be mulched. The mulch shall be a minimum four inches (4") in depth to decrease water evaporation. Nonporous material, such as plastic sheets, shall not be placed under the mulch.
   L.   The following types of trees shall not be used in landscaping as required by this chapter because of undesirable characteristics: Populus genus (poplars and cottonwoods), Salix genus (willows), Ulmus genus and Zelkova genus (zelkova) (elms), and Elaeagnus angustifolia (Russian olive).
   M.   If specimens of these trees exist on a site to be landscaped, they may be retained and counted towards the required number of trees. However, the property owner, or the individual responsible for landscape maintenance, must ensure that the trees are maintained in a manner to minimize the noxious characteristics of the trees.
   N.   All new landscaped areas shall be watered by a water conserving irrigation system including drip, low arching and/or low gallonage heads, as appropriate, controlled by an automatic timer.
      1.   Manual control of the irrigation system or hand watering may be permitted for landscape installations in preexisting paved areas which could not otherwise be trenched, or in isolated planters.
      2.   Drip irrigation is encouraged, where appropriate, to conserve water and inhibit weed growth.
      3.   Storm water and runoff harvesting to supplement drip irrigation are encouraged where possible for both new plantings and preserved vegetation. (Ord. 06-01, 1-25-2006)