LANDSCAPE AND TREE CONSERVATION [
Division 51A-10.100. In General.
SEC. 51A-10.101. DEFINITIONS.
In this article:
(1) AGE CLASS means a distinct group of
trees originating from a single natural event or regeneration activity i.e., a 10-year
age class, as used in inventory management.
(2) ANSI A300 means the American National
Standard for Tree Care Operations, including all parts, as amended.
(3) APPROVED TREE LIST means a list of
trees approved as replacement trees determined and maintained by the director.
(4) ARTIFICIAL LOT means an area within the
building site that is delineated by the building official or the director of
park and recreation for the sole purpose of satisfying the requirements of this
article (see Section 51A-10.122).
(5) BOUNDARY TREE means a tree growing on
a property boundary line between two lots resulting in joint ownership by the
adjacent property owners when the trunk exists on each property, or a tree that
has 20 percent or more of its critical root zone extending across a property
boundary and into an adjacent property.
(6) BROWNFIELD means a building
site, the expansion, redevelopment, or reuse of which may be complicated by the
presence or potential presence of a hazardous substance, pollutant, or
2]) CALIPER means:
field grown stock, the measurement of a tree taken six inches above ground
(B) for container grown stock, the
measurement of a tree taken six inches above soil level; which should be at or
near the top of the root flare, and six inches above the root flare for bare
root plants, up to and including the four-inch caliper size interval (i.e.,
from four inches up to, but not including, four and one-half inches);
(C) if the caliper measured at six inches
is four and one-half inches or more, the caliper must be measured at 12 inches
above the ground level, soil line, or root flare, as appropriate; and
(D) for trees with multiple stems, it is one-half
of the combined caliper of the three largest trunks. [
for a single-stem
tree, the diameter of the trunk measured 12 inches above the ground for a tree
having a diameter up to and including eight inches, and measured at four and
one-half feet above the ground for a tree having a diameter of more than eight
(B) for multi-stem trees, the diameter of
the trunk measured at the narrowest point below branching when branching occurs
higher than 12 inches above the ground. When branching occurs at or lower than
12 inches above the ground, caliper means the diameter of the largest stem plus
the average diameter of the remaining stems, measured at four and one-half feet
above the ground.
3]) CANOPY TREE means a species of tree that
normally bears crown foliage no lower than six feet above ground level upon
(9) CLASS 1 TREE means a tree located in a
primary natural area or geologically similar area measured to fifty feet above
the escarpment zone.
(10) CLASS 2 TREE means a tree that is not
(11) CLASS 3 TREE means Arizona ash, black
willow, cottonwood, hackberry, honeylocust, mesquite, mimosa, mulberry,
ornamentals, pinus spp., Siberian elm, silver maple,
sugarberry, or a small tree.
4]) CLEARING means any activity that removes or
seriously injures one or more trees or the vegetative ground cover of one or
more trees, such as root mat removal or topsoil removal
SOIL AREA means an area of soil that is under nonpermeable pavement and is designed
to accommodate tree root growth.
5]) CRITICAL ROOT ZONE means the circular area of
ground surrounding a tree extending a distance of one foot per diameter
[ caliper] inch of the tree, measured from the tree trunk or stem.
IMPACT AREA means the area of land or vegetation alteration within a property
including, but not limited to, clearing, grading, excavating, filling, and any
construction site operations, paving, or any other installation.
(A) the measure of a tree trunk measured
at a height of four and one-half feet above the ground (diameter at breast
height [“DBH”]), measured at the uphill side of the tree or as recommended in
the Landscape and Tree Manual for special situations for tree fork, lean, or on
(B) for trees with multiple stems, the
diameter of the trunk measured at the narrowest point below branching when
branching occurs below DBH, or near DBH; and
(C) when branching occurs at or lower than
12 inches above the ground, diameter means the diameter of the largest stem
plus the average diameter of the remaining stems, measured at DBH.
LINE means a vertical line that runs from the outermost point of the crown of a
tree to the ground.
6]) ENHANCED PAVEMENT means any permeable or
nonpermeable decorative pavement material intended
for pedestrian or vehicular use approved by the director. Examples
of enhanced pavement include, but are not limited to, brick or stone
pavers, grass paver, exposed aggregate concrete, and stamped and stained
7]) EVERGREEN TREE OR SHRUB means a tree or shrub
of a species that normally retains its leaves throughout the year.
(20) FACADE PLANTING AREA means the portion of
a lot abutting an active storefront or an office or mixed use building
8]) FLOOD PLAIN means any land area susceptible to
inundation by the hundred-year frequency flood.
(22) FOREST STAND DELINEATION (“FSD”) means
a comprehensive assessment of the conditions of a property using multiple types
of information, including, but not limited to, a tree survey, aerial imagery
collected from private or public sources, natural resources assessments,
topographic maps, management plans, a map of conservation areas, land use maps,
etc., to provide the required data to determine tree replacement requirements
and forest conservation objectives.
9]) GRADING means any digging, scooping, removing,
depositing or stockpiling, of earth materials.
COVER means natural mulch, or plants of species that normally reach a height of
less than three feet upon maturity, installed in such a manner so as to form a
continuous cover over the ground.
(25) HABITAT PRESERVATION AND RESTORATION AREA means a designated
area on a landscape plan dedicated to the restoration and preservation of an
undeveloped site either through active or passive management practices.
(26) HISTORIC TREE means a tree, or grove of
trees, that has been recognized by resolution of the city council as having
cultural or historical significance.
FREQUENCY FLOOD means the flood having a one percent chance of being equalled
or exceeded in any given year. This flood is based upon the drainage area being
fully developed to current zoning limitations
(28) INTERIOR ZONE means the area of a lot
not included in a street buffer zone or a residential buffer zone.
(29) INVASIVE PLANT means a plant that has
been classified as invasive to the Dallas region by Texas Parks and Wildlife or
the Texas Department of Agriculture.
ARCHITECT means a person licensed to use the title of "landscape
architect" in the State of Texas in accordance with state law.
AREA means an open soil area covered by natural grass, ground cover, or
other plant materials for the purpose of landscaping or the growth and
establishment of trees and other vegetation [ an area at least 80 percent
of which is covered by natural grass, ground cover, or other natural plant
materials (excluding screening)].
BUFFER STRIP means a landscape area that serves a buffer function.
SHRUB means a shrub that normally reaches a height of six feet or more upon
TREE means a tree [ of a] species that typically attains [ normally
reaches] a height and width of at least 50 [ 30] feet
at [or more upon] maturity, or as classified by the director.
(35) LEGACY TREE means a large or medium tree
planted in a landscape area for the specific purpose of actively establishing
and maintaining unencumbered sustainable large shade trees for future
(A) a "lot" as defined in Section 51A-2.102; and
(B) an "artificial lot" as defined in this section.
WITH RESIDENTIAL ADJACENCY means any of the following:
(A) A building site containing a multifamily use that is adjacent
to or directly across:
(i) a street 64 feet or less in width; or
(ii) an alley;
private property in a single family, duplex, townhouse, or CH district.
(B) A building site containing a nonresidential use that is
adjacent to or directly across:
(i) a street 64 feet or less in width; or
(ii) an alley;
from private property in an agricultural, single family, duplex, townhouse, CH,
multifamily, or manufactured housing district.
(C) An artificial lot containing a multifamily use if the lot is
less than 200 feet from private property in a single family, duplex, townhouse,
or CH zoning district.
(D) An artificial lot containing a nonresidential use if the lot
is less than 200 feet from private property in an agricultural, single family,
duplex, townhouse, CH, multifamily, or manufactured housing zoning district.
TREE means a tree which may typically attain a canopy height of 30 feet or
greater and between 15 feet and 50 feet in width at maturity, or as classified
by the director.
COVERAGE means coverage with any pavement that is not "permeable pavement”
as defined in this section.
(40) NURSERY STOCK means a plant grown in or
obtained from a nursery.
SOIL AREA means an unpaved area of soil.
PAVEMENT means paving systems, pavers, or other structural surfaces that
allow stormwater infiltration and are approved by the director [ a paving
material that permits water penetration to a soil depth of 18 inches or more.
Permeable pavement may consist of nonporous surface materials poured or laid in
sections not exceeding one square foot in area and collectively comprising less
than two-thirds of the total surface area].
(43) PEDESTRIAN PATHWAY means an area
intended for use by pedestrians or non-motorized vehicles
(44) PREVIOUSLY DEVELOPED SITE means a building site that has
been substantially altered through paving, construction, or other activity that
requires or required permitting or licensing through a regulatory agency.
(45) PRIMARY NATURAL AREA means an
ecologically sensitive area including 100-year flood plain and riparian areas,
wetlands or 50-foot wetland buffer, perennial and intermittent streams measured
to 50 feet above top of bank, and the escarpment zone.
PROPERTY means any property not dedicated to public use, except that
"private property" does not include the following:
(A) A private street or alley.
(B) Property on which a utility and public service use listed in
Section 51A-4.212 is being conducted as a main use.
(C) A railroad right-of-way.
(D) A cemetery or mausoleum.
(A) a tree of any species that has a minimum diameter of eight
inches that is not classified as unprotected in this article;
(B) any tree in a stand which projects a
tree canopy over a building site when identified within a forest stand delineation
a tree that has a caliper of eight inches or more and
is not one of the following trees:
(i) Acer saccharinum
(Silver Maple). (ii) Ailanthus altissima
(Tree of Heaven). (iii) Albizzia julibrissen
(Mimosa or Silktree). (iv) Celtis occidentalis/ laevigata
(Hackberry or Sugarberry). (v) Fraxinus velutina
(Arizona Ash). (vi) Juniperus virginiana (Eastern
Red Cedar) [unless protected under subparagraph (B)]. (vii) Maclura pomifera [female
only] (Bois d’Arc or Horseapple). (viii) Melia azedarach
(Chinaberry). (ix) Prosopis glandulosa (Mesquite)
[unless protected under subparagraph (B). (x) Salix nigra (Black
Willow). (xi) Sabium sebiferum
(Chinese Tallow). (xii) Ulmus
pumila (Siberian Elm).
(B) an Eastern Red Cedar (Juniperus
virginia) or Mesquite (Prosopis glandulosa) tree that has a caliper
of eight inches or more and the trunk is located:
(i) in, or within 120 feet of the
boundary of: a floodplain [as defined in Article V]; a wetland area [as defined
in federal environmental regulations]; or an escarpment zone [as defined in
Article V]; or (ii) within 50 feet of a natural channel
setback line [as defined in Article V].
(C) an Eastern Red Cedar (Juniperus
virginiana) or Mesquite (Prosopis glandulosa) tree that has a
caliper of at least 12 inches; or]
D]) a tree that was planted as a replacement tree.
OR SERIOUSLY INJURE means an intentional or negligent action that will more
likely than not cause a tree to decline and die within five years of the act.
Actions that constitute removing or seriously injuring a tree include, but are
not limited to: cutting down a tree; excessively pruning or topping a tree;
compacting the soil above the root system of a tree; changing the natural grade
above the root system of a tree; damaging the root system or the trunk of a
tree (such as by operating machinery near, or by clearing or grading the area
around, the trunk of a tree); failing to repair an injury to a tree from fire
or other causes, which results in or permits tree infections or pest
infestations into or on the tree; applying herbicidal or other lethal
chemicals; and placing nonpermeable pavement over the root system of a tree.
PARTY means the property owner and any other person or entity responsible for removing
or seriously injuring a protected tree.
TREE means a tree that is planted in accordance with Section 51A-10.134.
PATH means a path constructed using aeration or drainage strips providing roots
a route under pavement from a tree to an adjacent landscape area.
means screening that complies with Section 51A-4.602, except as those regulations may be expressly
modified in this article.
(53) SECONDARY NATURAL AREA means undisturbed
areas on a building site other than primary natural areas.
(54) SIGNIFICANT TREE means a healthy tree whose
age, size, unique type, or natural and historical character are of special
importance to the city, and meets the following species and size requirements
oaks with a minimum diameter of 12 inches
of the following species having a minimum 24-inch diameter: American elm, cedar
elm, chittamwood, common persimmon, eastern red cedar, green ash, all other oaks,
pecan, all walnuts species, and white ash.
TREE means a tree that typically attains a maximum height of 30 feet at
maturity or is classified as a small tree by the director [ of a species
that normally reaches a height of less than 30 feet upon maturity]
means a medium that plants will grow in.
means a group of trees or other growth occupying a specific area that is sufficiently
similar in species composition, size, age, arrangement, and condition, to be
distinguishable from adjacent forest.
(58) SUSTAINABLE DEVELOPMENT INCENTIVE (“SDI”)
means an alternative method of compliance that applies sustainable development,
tree preservation practices, and tree mitigation reductions based on providing
large or medium legacy trees in enhanced soil surface planting environments for
a projected increase of the tree canopy coverage on the property.
(59) TOPPING means the reduction of tree
size using internodal cuts without regard to tree health or structural
integrity. Topping is not an acceptable
(60) TREE CANOPY COVER means the amount of
ground area directly beneath a tree’s crown to the drip line or the combined
crowns of a stand of trees, measured in square feet.
(61) TREE REMOVAL PROPERTY means the lot,
parcel, right-of-way, or tract of land where a protected tree will be or has
been removed or seriously injured.
SURVEY means a report that meets all of the requirements for a tree survey in
(30) UNDERSTORY means a grouping of natural
low-level woody, herbaceous plant species, or plants that normally reach a
height of less than three feet upon maturity.]
(63) UNPROTECTED TREE means the following:
(A) Callery pear (all cultivars).
(C) Chinese tallow.
(D) Ilex species (except for yaupon holly
and Possumhaw holly.)
(E) Palm (all plants in Palmae).
(F) Tree-of-heaven or Ailanthus.
(G) Other trees listed as invasive plants.
(64) UNRESTRICTED ZONE means the area on a
lot where tree mitigation is not required.
(A) For front and rear yards, the
unrestricted zone does not include required setbacks or the area 15 feet from
the property line, whichever is greater.
(B) For side yards, the unrestricted zone
does not include required setbacks or the area five feet from the property
line, whichever is greater.
(65) URBAN STREETSCAPE means a
pedestrian-oriented street environment with required front yards with a depth
of 0 to 15 feet.
(31) VISIBILITY TRIANGLE means the term
"visibility triangle" as defined in Section 51A-4.602 .]
COURSE means a natural or constructed channel for the flow of water.