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consumption and environmental impact. Ac-
<br />cording to the EPA, the typical suburban lawn
<br />consumes 10,000 gallons of water a year above
<br />and beyond rainwater, creates grass clippings
<br />that consume 25 to 40 percent of landfill space
<br />during the growing season, and requires the
<br />use of lawnmowers with gas -powered engines
<br />that emit more hydrocarbons than a typical car
<br />(National Wildlife Federation n.d.).
<br />How can a community address this is-
<br />sue? Establish turf grass limits, and create
<br />landscaping standards that rely on the use
<br />of native and, where appropriate, drought -
<br />tolerant species. There are multiple examples
<br />of zoning codes across the country that either
<br />recommend limitations or establish specific
<br />restrictions on the amount of turf grass used
<br />to a relatively small percentage of the site,
<br />as well as communities that have sponsored
<br />turf grass buy-back programs. As an example,
<br />Rio Rancho, New Mexico, regulates turf grass
<br />to cover no more than 1,00o square feet or
<br />20 percent of the total lot area, whichever is
<br />less, while also prohibiting home owner as-
<br />sociations bylaws from requiring a minimum
<br />amount of grass (§154.o5.G).
<br />Avoiding watering issues altogether,
<br />some communities also permit the use of
<br />artificial turf, such as Simi Valley, California,
<br />which permits up to 75 percent of the land-
<br />scape area to be covered with artificial turf
<br />(§933.03o).
<br />Native and drought -tolerant plant materi-
<br />als along with non -plant groundcovers are
<br />both excellent primary plant sources in local
<br />landscapes and best choice substitutes for
<br />the use of turf grass. What is "native" is sub-
<br />ject to some scholarly discussion; however,
<br />most of the discussion circles around the
<br />idea that native plants "occur naturally in a
<br />particular region, state, ecosystem, and habi-
<br />tat without direct or indirect human actions"
<br />(Morse et al. 1999). Native plants have, over
<br />time, adapted to local soil and climate condi-
<br />tions, which means that they generally need
<br />less watering and fertilizing than non-native
<br />plants do. State and regional native plant lists
<br />are available online and are also typically
<br />available through state university agricultural
<br />and landscaping programs.
<br />Plants that may be able to survive in
<br />long-term drought conditions have differ-
<br />ent, and sometimes confusing, names. Xeric
<br />plants function normally in dry conditions.
<br />Drought -tolerant and drought -resistant plants
<br />use survival mechanisms, such as temporarily
<br />defoliating or going dormant, to survive dry
<br />conditions, but these plants still may die in
<br />prolonged drought situations (Silver 2015).
<br />"Native" and "drought -tolerant" are not in-
<br />terchangeable terms. Some native plants are
<br />xeric or drought tolerant; others are not. When
<br />drafting zoning standards, it is important to
<br />be specific about the category of plant the
<br />community wants to promote or require. This
<br />is best accomplished through good defini-
<br />tions, such as Sanford, Florida's definition of
<br />drought -tolerant: "native, non-invasive plants
<br />which will survive and flourish with compara-
<br />tively little supplemental irrigation," (Part
<br />III, Schedule J, §6.o) and this definition of
<br />xeriscaping from the University of Florida IFAS
<br />Extension: "landscaping with slow-growing,
<br />drought -tolerant plants to conserve water and
<br />establish a waste -efficient landscape" (2006).
<br />Within a zoning context, requirements
<br />for the preservation and planting of native and
<br />drought -tolerant plants can range from very
<br />general to very specific. Scottsdale, Arizona,
<br />starts by identifying native plants already on
<br />ments must achieve a minimum number of
<br />points based on the size of the site through a
<br />combination of plants chosen from the menu
<br />(§25-16.7). The city establishes a preference
<br />for the use of native Missourian plants in the
<br />intent section of the regulations as follows:
<br />"[p]romote the use of Missouri native plants
<br />that are more adaptable to the local climate
<br />extremes, are drought tolerant, low mainte-
<br />nance, and thus provide a sustainable, eco-
<br />logically balanced environment" (§25-16.2.H).
<br />The regulations then support this intent by
<br />allocating more points to the use of native
<br />plants. For example, Missouri native canopy
<br />trees are worth two points per tree, while
<br />other canopy trees are worth 1.5 points.
<br />The Miami -Dade County, Florida, Land-
<br />scape Code establishes the basic objective
<br />"to use xeriscape (Florida Friendly) principles
<br />to reduce water consumption, to expand the
<br />use of native species and to protect existing
<br />native habitats, to promote energy conserva-
<br />tion through the use of landscape and the use
<br />of landscape design as an integral part of the
<br />site and architectural design of our commu-
<br />nity" 618A -2(A)). The code establishes: (1) a
<br />maximum lawn area as a percent of net lot
<br />area—residential uses are permitted
<br />about 5o to 6o per cent lawn area—
<br />planted in "species well adopted
<br />to localized growing conditions
<br />in Miami -Dade County" (§18A -
<br />6(A)(1)); (2) a minimum num-
<br />ber of trees to be planted—"of
<br />a species normally grown in
<br />Miami -Dade County"—and 8o
<br />per cent of which are listed
<br />in the Miami -Dade Landscape
<br />Manual (§18A -6(C)(12)); and
<br />(3) a shrub mix that includes at
<br />least 3o per cent native species,
<br />5o per cent low maintenance and
<br />drought tolerant, and 8o per cent listed
<br />in the Miami -Dade Landscape Manual, the
<br />Miami -Dade Street Tree Master Plan, or the
<br />University of Florida's list of Low -Maintenance
<br />Landscape Plants for South Florida (§18A -6(D)
<br />(1)). The landscape plan review process con-
<br />siders the preservation of native vegetation,
<br />planting in hydrozones, use of native plant
<br />species, and reestablishment of native habi-
<br />tats (§18A-7).
<br />Finally, when considering water conser-
<br />vation in landscaping standards, communities
<br />should also review any irrigation standards
<br />in the zoning code. The type and design of
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<br />the site through the creation of a site-specific
<br />"native plant program" prior to construction
<br />(§§46 -1o5 -12o). Certain native plants, such
<br />as slow-growing desert trees and cacti, are
<br />protected, and the city uses the native plant
<br />program to work with the applicant to deter-
<br />mine how best to work around or relocate
<br />these plants.
<br />Maryland Heights, Missouri, uses a
<br />menu and point system for plant selection in
<br />its landscape design standards; all develop-
<br />ZONINGPRACTICE 9.15
<br />AMERICAN PLANNING ASSOCIATION I page 5
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