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Attached please find the revised ordinance inserts discussed at the workshop on August
21. Staff met several times this past week and completed the first draft revisions to
Chapter 82 and the Criteria Manual (also attached).
After much discussion, staff recommends that the BSC address the"core issues" of
Sections 82-3 and 82-4 and upon consensus with these two sections,proceed to revise the
rest of Chapter 82, leaving the criteria manual for last. This should enable the BSC to
remove those sections not necessary to the ordinance and put them into the criteria
manual with relative ease.
The "core" inserts were revised to a single qualifications table. Staff tried to work in the
idea of protecting higher-valued trees when there is an "elective" cut-down. With this
approach, there are two big "extra" protections for heritage trees: (1) BSC approval, and
(2) the replacement requirements will be significant if BSC agrees to move to "basal"
measurements for the trees.
Staff also recommends moving the "tree survey"requirement to Chapter 18 permitting
procedures under required documents. We will also be looking at changing the
application and permitting process so that the tree disposition and permit are actually
conditions of all permits issued for any development or pre-development activity. The
tree permit may also stand on its own when the activity is tree removal or tree protection
only.
cI • •
"Core" sections of Revised 8-30-07
revised tree ordinance
(inserts)
Section 82-3. Urban forest and tree protection.
(a) Generally. All persons have the duty to take reasonable steps to protect: (i) each six-inch-or-
larger tree, and (ii) each tree originally planted as a replacement tree. This duty includes all of the
following, whether included in a permit or not:
Permits. Obtaining tree permits when required by this Chapter.
Consent of owners. Obtaining the effective consent of all persons having a property interest in a tree before
beginning work that would damage the tree.
Physical protection. Physically protecting each tree(including its critical root zone)from damage from
nearby work,by following the criteria manual and any permit conditions. Exception: This does not apply
to damage authorized by a tree permit or to trees authorized to be removed.
Minimize,mitigate. Minimizing and mitigating any damage to the tree from nearby work,in accordance
with the criteria manual and any permit conditions.
(b) Building permits, development, etc. Each person holding a permit for development (or pre-
development activity) has additional and more specific duties (e.g., tree fencing) as prescribed by the
criteria manual or conditions of the permit. The building official and other issuing officials may insert
conditions reasonably calculated to enforce or carry out this Chapter into any permit for development or
pre-development activity.
Section 82-4. Tree permits.
(a) When required. A tree permit is required to damage or remove: (i) any six-inch-or-larger tree,
or(ii) any tree originally planted as a replacement tree.
(b)Applications. Any person may apply to the building official for a tree permit. The application
must include: (i) the City's standard application form, fully-completed and signed; (ii) the prescribed,
non-refundable application fee; (iii) a tree survey(if required by the criteria manual); and (iv) a
replacement tree planting plan(if required by the criteria manual).
(c)Issuance. The building official is the issuing official. Exceptions: (i) Any permit to remove or
damage a heritage tree requires approval by the BSC. (ii) The building official may refer an application
to the BSC, if it appears to involve an especially high impact upon the urban forest of the City, or if the
applicant does not clearly and convincingly prove the qualifications for the permit. If an application is
referred to the BSC, issuance of the permit requires approval by the BSC. The building official and BSC
shall consult with the urban forester about applications and permits. Any permit may contain conditions
'reasonably calculated to enforce or carry out this Chapter.
(d) Qualifications for permits. A permit for removing or damaging a tree shall be issued if: (i)
the application complies with this Chapter, the criteria manual and other applicable regulations, and (ii)
the following qualifications have been proved, as applicable:
4 , • •
Replacement
Table 82-3(d).2. Qualifications for a permit to remove or damage a tree required;see
(e),below
Note:All the Low-value. The tree is a low-value tree. No
qualifications in
one or more of Hazard. The tree is a potential,unavoidable safety hazard(disregarding any No
these categories proposed structures).
must be proved,
for each tree Diseased,damaged,dead,suppressed. The tree is(i)dead,(2)terminally No
permit. diseased,(iii)severely damaged or(iv)severely suppressed by other tree(s).
Excess trees and good canopy cover. Other trees will remain,and:(i)the No
affected area will have 200%or more of the minimum planting standard,(ii)the
average value of the remaining trees will be the same or higher than the average
value of the pre-existing trees,in the affected area,and(iii)there will be canopy
cover above at least 60%of the affected area. Canopy cover may be provided, in
part,by trees located outside the affected area.
Interference with existing use. The tree interferes with a lawful and reasonable Yes
existing use of the affected area,and:(i)the use has been reduced or modified,to
the extent feasible,to avoid removing or damaging the tree,(ii)there is no
reasonable means of accommodating the reduced or modified use while avoiding
removal or damaging the tree,and(iii)it is not feasible to remove or damage a
lower-valued tree instead.
Interference with proposed use. The tree will interfere with a lawful and Yes
reasonable proposed use of the affected area,and:(i)the area of the proposed use
(e.g., foundation"footprint")has been reduced or modified to the extent feasible,
to avoid removing or damaging the tree,(ii)there is no reasonable arrangement
or design of the reduced or modified use that would avoid removing or damaging
the tree,and(iii)it is not feasible to remove or damage a lower-valued tree
instead.
(e) Replacement trees. When indicated by"Yes," above, the holder of a tree permit must provide
replacement tree(s) in accordance with the criteria manual. This duty applies whether mentioned in the
tree permit or not.
S •
Chapter 82 URBAN FOREST PRESERVATION AND ENHANCEMENT
Sec. 82-1. Purpose; findings.
(a) Purpose . The purpose of this chapter is to preserve and enhance the urban forest of
the city. This chapter protects all trees 6 inch diameter and larger and requires permit
application prior to removal or damage to any tree 6" diameter or larger.
(b) Findings . The city council has determined the following: The urban forest is of
great value in the maintenance of public health and welfare. The urban forest can aid in
the conservation of vital energy resources and natural resources and in the preservation of
the city's heritage and quality of life. Trees are a valuable amenity to the urban
environment, creating greater human comfort by providing shade, cooling the air through
evaporation,restoring oxygen to the atmosphere, reducing storm water runoff through
rainfall interception b foliage
and_branches,reducing glare, reducing noise levels,
providing an ecological habitat for songbirds and other animal and plant species,
providing for more effective transitions between different land uses and breaking the
monotony of urbanized development, pre-development, or construction. The urban forest
of the city should be preserved and enhanced, to the maximum extent feasible, consistent
with the property rights of its citizens.
Sec. 82-2. Definitions.
Unless the context otherwise clearly requires a different meaning,the following terms, as
used in this chapter, shall have the meanings indicated below.
Criteria manual means the "criteria manual" dated February 1—94August 2007, a copy of
which is on file in the office of the city secretary, which is hereby approved, adopted and
incorporated into this chapter by reference.
Critical root zone means, for any given tree,the circular area measured outward from the
tree trunk representing the essential area of roots that must be maintained or protected for
the tree's long term survival. -•- • - -• - . - -- • - o • o -. The Critical
Root Zone area shall be one foot of radial distance for each inch of tree DBHdiameter.
For trees larger than 12 inch diameter, located within 8 feet of street curb, the
Critical Root Zone area shall be one and a half feet of radial distance for each inch of tree
DBH. Areas beneath curb and gutter streets, concrete house, garage, or other structure
foundations shall not be included as part of the Critical Root Zone.
See figure lb attached to the criteria manual.
Damage a tree means to take any action which causes or may reasonably be expected to
cause the tree to die including, without limitation, damage inflicted on greater than 30%
of the Critical Root Zone by machinery, storage of materials, pouring or spilling of
noxious chemicals or solvents, or soil compaction on greater than 30% of the Critical
• •
Root Zone; substantially changing the natural grade on greater thatn 30% of the Critical
Root Zone; pruning of more than 30% of a tree's canopy;paving with concrete, asphalt,
or other impervious materials over greater than 30% of the Critical Root Zone; or failing
to comply with specific direction provided in a tree disposition plan and permit.
• - •, • - •� : • - _ • in trunk or large branches or large roots,
. . . . . . . . . . . . . . .
-- - •• ••• •- criticalroot zone, covering a substantial part of the critical
- ' •: •• • : = - - Diameter shall mean the tree trunk diameter measure
in inches at a height of 4.5 feet (54 inches) above natural grade for all trees that measure
6" diameter or larger. Tree trunks that branch at a point lower than 4.5 feet shall be
measured at the smallest point below the lowest branch. On multiple trunk trees take the
measurement of the diameter of the largest stem and 1/2 the diameter of all remaining
stems 1" diameter or larger. Trees that measure less than 6" at 4.5 feet above natural
grade shall be measured at 6" from natural grade or planting media—the measurement at
6" from grade shall be the tree's diameter. If a diameter tape is not used a standard tape
measure can be used to determine tree circumference which can be converted to diameter.
Divide the circumference measurement by 3.142 to obtain diameter.or the DBH•.. . . - . . -- . .- • .. . •. Off-tree-trunks-that
"- • .• •• " . "- • • "- •• • . . -:Heritage Tree means a Class I or Class II (see
appendix) tree with a DBH of 255 inches or more and is evaluated at 35 points or
higher per the criteria manual. In case a tree is removed, it is presumed to have been an
heirloom or heritage tree if the diameter of the stump is 30 inches or greater, measured in
any direction.
inches or greater, measured in any direction.
Located. A tree is "located" within an area if any part of its trunk is within the area at
ground level.
Low-value tree means a tree included in "Klass IV" of the criteria manual(see appendix)
which is evaluated by the urban forester under the criteria manual and assigned a total•
rating less than 30 - . A ! .. . - .. .
• •
Minimum lan
p tang standard means the minimum standard for total number of Qualified
trees which must be present on a site regardless of the number of pre-existing or
replacement trees, as set forth in the criteria manual.
ground.
Protected tree includes:
(1) A significant12 inch diameter or larger tree anywhere in the city;
(2) A large6" diameter or larger tree located within any of the following:
a. etween public right of way and a front or side building set back;
b. A street side yard(of corner sites); or
eb. A right-of-way area and
(3) When a permit has been applied for, or when is a permit in effect for
development or pre-development activity on any subject site, "protected tree" includes all
large-trees 6" diameter and larger located on that subject sitelot and the adjacent right of
way.
Qualified tree means any tree listed in Class I or II of the criteria manual, which has a
trunk diameter of at least t . > >k inches, measured six inches above the ground.
Remove means to cut down, or remove a tree by any other means.
Replacement tree means a tree meeting the minimum criteria for replacement trees as set
out in the criteria manual and this chapter.
Replacement tree planting plan shall mean a plan submitted by the permittee in a form or
manneras : . ... - set out in the criteria manual providing the
method of replacement for required replacement plantings, that identifies the location,
size, and species of all new trees proposed as replacement for the protected trees being
removed and/or any Tree Trust or Urban Forestry Enhancement Fund credits in lieu of
replacement plantings.
Right-of-way area includes all parts of a street area, including:
(1) The paved or improved roadway;
(2) The sidewalks;
(3) The curbs or ditches; and
(4) All other paved or unpaved areas in the street area. The "right-of-way area"
for an individual sitelot includes only the area between the property line of the site
and the centerline of the street area(i.e., the directly abutting area in the street
area). A corner site has a right-of-way area both in front and on the side.
• . - , ••-.. . . . ., . , . (Also see definition of large
tree.
• •
Street gutter flow line means the street gutter flow line of the curb adjacent to and
bordering upon a visibility triangle. If there is no curb, the height restrictions set forth in
this chapter shall be based upon the actual level of the street area adjacent to and
bordering upon the visibility triangle.
Tree means any woody plant having a ene-well-defined stem or trunk,and a more or less
definitely formed canopydefne crown usually attaining a height of at least 8 feet; and-a
mature-height of at 1 t eight feet. However under certain environmental conditions
some tree species may develop multiple trunk or shorter growth form.
Tree : ' :: ' •: : . • permit means conditions approved by the urban forester
pertaining to -- :' :: ' •. .-; the protection and replacement of trees when
development or predevelopment activity occurs. Sec section 82 3. criteria manual for tree
permit requirements associated with development or predevelopment activity. Tree
permit also means a permit issued by building official authorizing removal of or damage
to a tree.
damage to a protected tree.
. . - -- , - , . . - - - - - - - -, . . - , . ., .n ..- .
Tree trust means any person or entity which meets all of the following criteria:
(1) It is operated on a profit-making or not-for-profit basis;
(2) The urban forester has determined that it has the resources, organization and
expertise to plant and maintain trees successfully in an urban setting and in
compliance with certificates issued to the city; and
(3) The urban forester's determination has not been revoked or suspended.
S
Urban Forest Enhancement Fund or "UFEF" means the fund established as such by this
chapter.
Urban forester means a person so designated and acting under this chapter.
Visibility triangle means the area at a street corner lying within a triangle beginning at the
precise intersection point of the curbs of each of the two streets forming the corner and
extending 20 feet along each curb line away from the curb intersection point, with the
third side being determined by drawing a straight line connecting the ends of such 20-foot
extensions. If there is no curb on such a street, the 20-foot line defined in zoning
ordinance shall follow the central flow line of the ditch paralleling the uncurbed street.
The visibility triangle may include both public and private property.
Sec. 82-3. Tree disp permits.-
(a) GeneralWhen requirenwnnd-_Every building permit for development or
predevelopment activity --. . . -- . .. ' ': -must also be issued a tree permit
that will ensure-cendis-meeti -_the requirements of this section are satisfied. A tree
permit is also required to damage or remove: (i) an y six-inch-or—larger tree or ii an
tree originally planted as a replacement tree.
(b) Essential and mandatory conditions. -- .•
.. • . ., • .
- -. - • . •: : . velopmcnt activity. Tree permit shall:
(1) Prohibit removal of or damage to any protected large-tree, except:
(a) Removal of a tree which is terminally diseased, severely damaged or
dead may be authorized;
(b) Damage to or removal of a tree which causes an unreasonable
impediment to the use and enjoyment of the applicant's property may be
authorized; and
c. c. Damage to or removal of a low-value tree may be authorized:
Comr ission,-dDamage to or removal of a tree or trees (excluding
Heritage trees) •- . - - .,•. .,•. . . . --
u t that are suppressed by larger trees, or a tree that is
suppressing a Class 1 or 2 tree may be authorized only if the following
conditions remain:
i. Enough trees will remain on the affected lot to maintain 2.5
times the Minimum Planting Standard as included in the
Criteria Manual.
ii. Enough trees will remain to provide canopy cover above at
least 60% of the affected lot. • e .. : - , : •• •
. • ..t - - •
e. With a special exception authorized by the Building and Standards
Commission, damage to or removal of an-heirloom-Of hHeritage tree
may be authorized if the replacement plantings meet twwe1.5 times the
DB14-diameter in replacement inches as per the replacement
requirements of this chapter.
(2) Require Require replacement trees, to the extent provided in the criteria
manual, for any large trees 6 inch diameter and larger authorized to be damaged
or removed. - - . - - . . ••- - • . . . . . --
(3) Require Require protection for large-trees 6 inch diameter and larger(and
critical root zones). The conditions may specify the methods of protection to be
used.
(4) Require Require that any authorized damage to trees be minimized and
mitigated. The eenditienspenuit may specify methods of mitigation to be used.
(5) d 5,1- Require, if there is major development, that the affected subjeet-sitelot
attain a minimum planting standard of tree density as set forth in the criteria
manual.
(6) Require the submission of a tree replacement planting plan subject to the
approval of the Urban Forester.
(c) Proccd treIssuance. The building official shall not issue any permit for any
development or predevelopment activity prior to approval of the Tree Permit.-unless-all
(d) "Low-impact"exception. Except for the requirement to insert the mandatory
conditions, this section does not apply to a subject site, project or other activity that will
not have any significant, adverse effect upon any large tree, as determined by the urban
forester.
Sec. 82-4. Tree permits application.
(a) Applications.- • -- - . • -. .' • . . - - ..., ,
requirement a tree permit.1
. •
. - .. - - . •- : .• . .•• ..•- . • • . -• . . • ••
criteria as established in Section 82 3 (b) 1 (e). Any person may apply to the building
official for a tree permit. The application must include the following_
(1) Tree Removal permit not associated with development or pre-development
activity:
a. Completed and signed"Permit Application For Tree Removal"
(2) Tree Permit associated with Development or predevelopment activity:
a the City's standard application form, fully completed and signed
b the prescribed application fee;
c a tree survey, per the Criteria Manual; and
d a plan of proposed development or predevelopment activity, per the
Criteria Manual
Sec. 82-5. Replacement trees.
(a) Number of replacement trees. Tree :..:; = = = •: • •• : " permits
authorizing removal of or damage to large-ttrees 6" diameter and largeror protected trees
shall normally require replacement by one or more newly-planted trees on the same
subject sitelot according to the "replacement inch" stipulations in the criteria manual. To
the extent on-site replacement is not feasible, the permittee may choose to:
(1) Plant and maintain off-site replacement trees within 1,000-feet of the subject
site, subject to the provisions of the criteria manual;
(2) Provide a replacement-inch certificate from a tree trust or the UFEF, as
provided in this section and the criteria manual; or
(3) Provide replacement inches by some combination of the foregoing methods.
Regardless of the method or methods chosen, the number of replacement inches
planted on the subject site, plus those provided by alternate methods, must equal
or exceed the number calculated according to the replacement inch stipulations in
the criteria manual.
(b) -Minimum size. Replacement trees must normally have a trunk diameter of at
least two six inches measured six inches from the ground st e -it- --
Class 1 or 2 tree. If tenfifteen inches or more of replacement inches are required
by a permit, one replacement tree for each tenfifteen inches must have a trunk
diameter of at least four-eight inches, measured six inches from the ground and
•
be a Class 1 tree. Example: If 2437 replacement inches are required, there must
be at least two replacement trees with a trunk diameter of-freight inches or
more. . .., . - - ,. . - - •- . ... ,. - . .. -
(c) Minimum Open and Pervious Growth Area. Each replacement tree must be
planted within a contiguous open and pervious-area of at least 500 square feet.
This area must be represented and approved by the Urban Forester in the
replacement tree planting plan.
(d)e) Qualified trees under zoning ordinance. To be a"qualified tree" under the zoning
ordinance, a tree must comply with the definition of"qualified tree" set out in section 82-
(de) Trees in street areas. Before authorizing the establishment or maintenance of a tree
or decorative landscaping (or any related appurtenances such as lighting or a watering
system) in a street area, the building official must:
(1) Be satisfied that V.T.C.A., Transportation Code ch. 316 has been complied
with; and
(2) Determine there would be no violation of the provisions of this chapter
relating to visibility triangles.
The building official is designated by the city council to make the determinations
contemplated by V.T.C.A., Transportation Code § 316.003.
GI) Replacement inch certificates. If a tree trust or the UFEF issues an effective
"replacement inch" certificate to the city, as provided in the criteria manual, the
"replacement inches" described in the certificate are treated the same as replacement tree
inches actually planted as of the date of the certificate.
(h=) Replacement inch credits. An owner of a sitesite in the city who plants a class I or
class II tree on that site is eligible to receive a credit for future "replacement inches." The
owner may use the credit to offset the number of"replacement inches" assessed for
protected trees removed from the same site at any time in the future. Credits are subject
to the following:
(1) Issuance. Credits are only available for trees registered with the urban
forester within 30 days following the day they are planted. Registration requires
application and proof of planting. The registration form shall specify the size and
species of each tree planted and its location on the site.
(2) Measurement. The number of replacement inches actually credited is
determined by the urban forester at the time an offset in requested, based on the
health and size of the previously-registered trees and applying the provisions of
the criteria manual regarding calculation of replacement inches.
(3) Transferability. Credits are not transferable to another site but may be
claimed by subsequent owners of the same site.
•
(4) Records. The city is not responsible for keeping registration or other records
of credits. A person claiming a credit must present documents to show that the
credit is available and applicable.
(I t) Urban Forest Enhancement Fund . The urban forest enhancement fund(UFEF) of
the city is hereby established. The UFEF is subject to all restrictions on public funds and
other funds of the city, including the requirement for annual budgeting. However, money
in the UFEF may only be budgeted and spent for the following purposes:
(1) Purchasing, planting or otherwise providing trees in public spaces in the city;
(2) Maintaining or otherwise enhancing trees in public spaces in the city; or
(3) Matters necessary or incidental to the above.
Deposits may be made into the UFEF by gift or other transfer. The director of finance is
authorized to accept such deposits on behalf of the city and to issue:
(1) Acknowledgments in the name of the city; and
(2) "Replacement inch" certificates as provided in the criteria manual.
Sec. 82-6. Protective fencing.
(a) Fences required . Unless otherwise specified in the applicable tree disposition
eenditionspermit, each protected tree to be preserved must be fenced during development
or predevelopment activity.
(b) Fence criteria . The tree :• :. • •.- permit shall specify protective
fencing of the critical root zone whenever reasonably practicable, unless a different area
is prescribed in accordance with the criteria manual. Unless the tree disposition
conditions specify otherwise:
(1) A six-foot or higher fence must surround each protected tree or group of
protected trees, effectively preventing people,machinery, trash, material and
other items from occupying the area within the protective fencing;
(2) The fence must be constructed of dtwat7k_ 11Q111-- materialschain link
or wood materials supported on poles firmly set in the ground;
(3) The fence must be able to resist intrusions and impacts likely to be
encountered on a construction site;
(4) The fence may incorporate existing fences or walls as well as temporary
fencing; and
(5) Each fence must display a prominent warning sign as set forth in the criteria
manual.
(c) Fence permit. A separate fence permit is not required for construction of a fence
under this section, if a permit for the work is in effect and includes tree disposition
conditions.
(d) Trash, storage prohibited. It shall be unlawful for any person to use the area within
the protective fencing, required by this section, for trash disposal, storage, vehicle
parking or any other use that could adversely affect tree roots.
• •
Sec. 82-7. Visibility triangles.
It shall be unlawful for any person to plant, grow or maintain any plant, except a tree,
within a visibility triangle, if the plant has (or probably will have) a height greater than
three feet above the street gutter flow line. It shall be unlawful for any person to plant,
grow or maintain a tree which has branches or foliage within or above a visibility triangle
at a height lower than 15 feet above the street gutter flow line. It is presumed that a
person who owns or controls real property within the city maintains all trees and plants
on that property. The city may enter a visibility triangle and remove growths prohibited
by this section, and there shall be no liability to others for taking or not taking such
action.
Sec. 82-8. Administration; appeals, etc.
(a) Urban forester. The city manager shall appoint an experienced and qualified person
to be chief urban forester for the city. The city manager may designate one or more other
urban foresters to act in the absence of the chief; persons so designated may not
necessarily be employees of the city, but the city manager shall make an adequate
provision for obtaining their services by contract if they are not city employees. A person
designated as urban forester must hold at least a bachelor's degree from an accredited
four-year college or university in urban forestry or arboriculture or must have equivalent
skills and experience.
(b) Referral; duties. The building official shall refer tree surveys, tree-disposition
conditions and applications for tree permits to a designated urban forester, who shall
work with the applicant and other city departments as required to administer the
provisions of this chapter. The urban forester may establish categories of simple, routine
or low-risk surveys, plans and applications, which may be handled summarily, without
submission to the urban forester. The fees for such applications may be reduced
accordingly, if so provided in the fee schedule.
(c) Applicability to city projects. For all city projects that may impact large-trees 6 inch
diameter or larger,the appropriate documents (tree permits, tree surveys tree
• : •: • :•=• - ) shall, whenever practicable, be submitted to the urban forester for
evaluation and recommendations, prior to public hearings (if held) or final decisions
taken by city council or city staff. City approval of a city-owned subject site or project
shall constitute approval for actions affecting the trees. City-owned subject sites or
projects shall follow the same guidelines for tree replacement as private subject sites or
projects, except as authorized by the city council.
(d) Reference and training. The city manager is authorized to obtain training and
reference materials for the building official and other city staff members who may be
called upon to enforce this chapter. The building official is authorized to maintain
reference materials on file and to make them available, without charge, to persons who
request information in connection with construction or other activities within the city that
could affect the urban forest.
(e) Cooperation. It is the desire of the city to establish a cooperative working
relationship with persons seeking to improve property within the city. Interested persons
are invited and encouraged to meet and confer with city staff and to retain the services of
expert foresters to provide advice and assistance to themselves and the city. The urban
•
forester shall use reasonable best efforts to determine the type and amount of replacement
trees required in an attempt to minimize any undue burden resulting from this chapter.
(f) Decisions and appeals. When making decisions or performing other duties under this
chapter,the urban forester and the building official both shall be subject to the standards
and procedures generally applicable to the building official under this chapter. Appeals of
decisions made by either the building official or the urban forester, and applications for
variances and special exceptions, are heard by the building and standards commission, in
accordance with this chapter. Notwithstanding any other provision to the contrary, the
commission, when considering an application for a variance:
(1) Shall take into account efforts to avoid or mitigate removal of and damage to
trees, particularly trees highly-evaluated under the criteria manual or heritage of
heirk: - °cad,; and
(2) May take into account the financial cost of compliance with this chapter,
particularly as it compares to the cost of other work the applicant may be
proposing.
Sec. 82-9. Violations.
(a) Removal, damaging, killing of protected trees. Except as authorized by a tree permit,
it shall be unlawful, within the city:
(1) For a person to remove or damage a protected tree intentionally or
knowingly;
(2) For a person, who owns or controls any site, intentionally or knowingly to
cause or allow a protected tree to be removed or damaged, if it is located within
that site or the right-of-way area of that site.
(b) Affirmative defenses. It shall be an affirmative defense to prosecution under this
chapter for removing, damaging or killing a tree, that:
(1) Tree :• .. •. .. . .•• . . ..' . . - - - •- ` permit
authorized the conduct in question;
(2) All of the following four circumstances were present:
a. Immediate action to remove, damage or kill the tree in question was
necessary to prevent harm to people or property;
b. A permit application was filed within ten days thereafter;
c. An appropriate permit or amendment was obtained; and
d. There was full compliance with all conditions of the permit or
amendment.
(c) Conditions. It shall be unlawful for any person who applies for or receives a permit
regulated by this chapter to fail or to refuse to comply with a condition of the permit or
this chapter. Any related permit for the subject site in question may be withheld until the
condition is complied with to the satisfaction of the urban forester, building official or
any other city staff members who are called upon to enforce this chapter. All permits are
subject to revocation or suspension as provided for in chapter 18.
Sec. 82-10. Other regulations; conditions.
(a) Conflicts with other regulations. In any case where another city ordinance, rule or
regulation would require the removal, damage or death of a large tree, under
circumstances where this chapter would prohibit such action, it is the intent of the city
• •
council that all of the applicable regulations shall be read together and harmonized so
that, if reasonably practicable, the large tree is not removed, damaged or killed.
(b) Liberal interpretations authorized. All city officials, boards and commissions are
authorized and encouraged to interpret other ordinances, rules and regulations liberally in
order to minimize conflicts with this chapter and to protect existing large trees, except in
circumstances where there might be hazards to persons or property.
(c) Variances. The need to protect or preserve a large tree shall be considered a
sufficient "hardship" in all cases where a hardship is required for the issuance of a
variance under city ordinances, unless additional grounds are required by state law.
CRITERIA MANUAL
FOR THE URBAN FOREST
of the
CITY of WEST UNIVERSITY PLACE, TEXAS
August 2007
• •
TABLE OF CONTENTS
INTRODUCTION:PHILOSOPHY AND GENERAL RULE 4
1.TREE SURVEY STANDARDS 4
1.1 REQUIRED FIELD DATA 4
1.1.1 Location 4
1.1.2 Diameter(Circumference) 4
1.1.3 Type(Species) 4
1.1.4 Critical Root Zone. 5
1.2 RECOMMENDED ADDITIONAL FIELD DATA 5
1.2.1 Crown Clearance 5
1.2.2 Condition 5
1.2.3 Spot Elevation 5
1.3 PLAN GRAPHICS 5
1.3.1 Trunk Location 5
1.3.2 Critical Root Zone(CRZ);Crown;Retained Trees 5
1.3.3 Sizes and Types 6
2.TREE EVALUATION AND SITE PLANNING 6
2.1 TREE EVALUATION 7
2.1.1 Tree Evaluation Method 7
2.1.2 Condition 7
2.1.3 Type 7
2.1.4 Size 8
2.1.5 Screening;Aesthetics 8
2.1.6 Energy Conservation and Heat Abatement 8
2.1.7 Safety 8
2.1.8 Adjacent Trees 9
2.1.9 Water Quality Protection and Soil Conservation 9
2.1.10 Wildlife Habitat 9
2.1.11 Historical significance 10
2.2 TREE PRESERVATION CRITERIA 10
2.2.1 Root Zone Impacts 10
2.2.2 Crown Impacts 11
2.2.3 Deviations from Criteria 11
2.3 DESIGN CONSTRAINTS AND ALTERNATIVES 11
2.3.1 Permeable Paving 11
2.3.2 Building Alternatives 12
2.3.3 Sidewalks 12
2.3.4 Grading 12
2.3.5 Utilities 13
3.MITIGATIVE MEASURES AND REPLACEMENT TREES 13
3.1 MITIGATIVE MEASURES 13
3.1.1 Tree Maintenance 13
3.1.2 Special Construction Techniques 13
3.2 REPLACEMENT TREES 14
3.2.1 Quantities of Replacement Trees 14
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3.2.2 Available Planting Area: On-site and off-site Replacement 15
3.2.3 Survival Potential;Irrigation and Maintenance 15
3.2.4 Types of Replacement Trees 15
3.2.5 Minimum Standards For Total Number of Trees 15
3.2.6 Enforcement Criteria;Delayed Planting 16
4.TREE PHYSIOLOGY 16
APPENDIX A: CLASSES OF TREES 19
APPENDIX B. WARNING SIGN REQUIRED FOR TREE PROTECTION FENCES -)3
LIST OF FIGURES
Figure 1.Measurement of various tree configurations
Figure 1.b Example of crown area measurement
Figure 2.Example of typical plan graphics
Figure 3.Aeration systems for trees in fill areas
Figure 4.Retaining walls to mitigate cuts and fills
Figure 5.Minimizing root impact by boring
Figure 6.Tree Structure And Physiology
IMPORTANT NOTE
This manual is to be used and interpreted in accordance with the City's ordinances on urban forest preservation
and enhancement,codified as Article XIV of Chapter 82 of the City's Code of Ordinances. Unless the context
indicates that another meaning is intended,terms used in this manual have the same meanings as in Article XIV.
CRITERIA MANUAL (August 15,2007) Page CM--3
• •
INTRODUCTION:PHILOSOPHY AND GENERAL RULE
It is the intent of the City to preserve the Urban Forest as a whole through two approaches:
O Preservation or replacement of existing trees. The City seeks to: (i)avoid tree damage wherever
feasible;(ii)mitigate damage when it occurs;(iii)require on-site replacement of trees that must be
removed,and(iv)require off-site replacement of trees that cannot be replaced on-site,either by direct
planting or through a Tree Trust or Urban Forestry Enhancement Fund.
O Require sites where major development takes place to attain a Minimum Planting Standard for trees,
regardless of the number of pre-existing trees.
1.TREE SURVEY STANDARDS
1.1 REQUIRED FIELD DATA
Tree data submitted for a Tree Survey or Tree Permit must be obtained from a ground survey. The data that
must be obtained in the field are Tree locations,Diameter,type(species),and critical root zone areas.
1.1.1 Location
Tree Surveys must be as accurate as possible,but need not be certified. Levels of inaccuracy that will result in
a failure to comply with the City ordinance and construction specifications may necessitate new surveys and
plan adjustments prior to permit approval.
Trees on City Right of Way or easements adjoining the site must be surveyed.
Trees with 30%or more of their Critical Root Zones extending onto an affected Site or project must be
surveyed. Trunk locations of off-site Trees may be estimated to avoid trespass problems.
Methods for locating Trees may vary depending on the size of the project and number of Trees. In most cases,
taping the distance to the center of the trunk from two(2)known points is a viable option.
1.1.2 Diameter(Circumference)
The Diameter of a tree shall be measured at a height of 4.5 feet(54 inches)above natural grade for all trees that
measure 6"diameter or larger. Tree trunks that branch at a point lower than 4.5 feet shall be measured at the
smallest point below the lowest branch. On multiple trunk trees take the measurement of the diameter of the
largest stem and' the diameter of all remaining stems 1"diameter or larger. Trees that measure less than 6"at
4.5 feet above natural grade shall be measured at 6"from natural grade or planting media—the measurement at
6"above grade shall be the trees diameter. If a diameter tape is not used a standard tape measure can be used to
determine tree circumference which can then be converted to diameter. The circumference measurement can be
divided by 3.142 to obtain diameter. Circumference measurements shall be taken at 4.5 feet for all trees that
measure 19"in circumference and larger and at 6"from natural grade for all trees that measure less than 19"at
4.5' from natural grade.
1.1.3 Type(Species)
Tree types should be accurate to the species level and may be listed by common names or botanical names(e.g.
Post Oak or Quercus stellata).
Good field references for Houston are: Texas Trees,a Friendly Guide,by Paul W.Cox and Patty Leslie
CRITERIA MANUAL (August 15, 2007) Page CM--4
• •
(available from Chickadee Nature Store,713-956-2670);the Trees For Texas Resource Guide,available from
the Texas
Department of Agriculture,512-463-7504;Field Guide to Texas Trees,by Benny J.Simpson;and Trees,Shrubs
and Woody Vines of East Texas,by Elray Nixon.
1.1.4 Critical Root Zone Area
The Critical Root Zone(or"CRZ") means,for any given Tree,the circular area measured outward from the tree
trunk representing the essential area of roots that must be maintained or protected for the tree's long term
survival. The Critical Root Zone area shall be one foot of radial distance for each inch of tree diameter. For
trees 12"diameter located within 8 feet of street curb,the Critical Root Zone area shall be one and a half feet of
radial distance for each inch of tree diameter. Areas beneath curb and gutter streets,concrete house or garage
foundations shall not be included as part of the Critical Root Zone Area.
1.2 RECOMMENDED ADDITIONAL FIELD DATA
1.2.1 Crown Clearance
This information is often critical in determining whether a given structure can practically be placed within the
dripline of a Tree. If this information is recorded,the surveyor should consider the vertical distance to any
major branches.
1.2.2 Condition
This is one of the principal factors in determining whether a Tree should or should not be preserved. Surveyors
should not speculate about the condition of Trees unless they have the necessary credentials;however,if a Tree
is obviously in poor condition,it should be noted.
1.2.3 Spot Elevation
Taking an elevation reading near the trunks of some Trees will provide valuable information for project
designers. Since grade changes have a very destructive impact on Trees,it is important to get the most accurate
information possible.
1.3 PLAN GRAPHICS
The standard Tree graphics discussed below are important to provide consistent information in the most useful
format for efficient plan review.
1.3.1 Trunk Location
The trunk location on the plan must represent the center of the trunk at ground level. If the Tree leans
substantially above that point,show the direction of the lean with an arrow.
1.3.2 Critical Root Zone(CRZ); Crown;Retained Trees
The Critical Root Zone should be indicated by a circle centered on the trunk. The actual crown may also be
shown if it is skewed and will have a significant impact on construction.
Trees proposed to be retained are to be represented by circles drawn with a solid line,while Trees proposed to
be removed do not require critical root zone to be represented. Proposed replacement Trees should be shown on
plan with critical root zone represented with a dashed line.
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1.3.3 Sizes and Types
Tree diameters and species must also be shown on the plan. This information should be shown adjacent to each
trunk location. For sites with a large number of Trees,this data should be shown in legend form referenced by a
Tree number adjacent to each trunk location. Legends can be useful because they allow for the presentation of
other data such as crown configuration,height,condition,etc.
1.4 SMALL-SCALE PROJECTS
The Urban Forester may prescribe the contents for a simple,low-cost Tree Survey for small-scale projects. For
these projects,the Urban Forester may allow the deletion of some data and details otherwise required and may
make provisions to assist lay persons preparing their own surveys.
2.TREE EVALUATION AND SITE PLANNING
The Urban Forester shall use the following criteria to evaluate Trees shown in Tree Surveys and,working with
the applicant and City building officials,the Urban Forester shall prepare or approve Tree Disposition
Conditions complying with Chapter 6 of the Code of Ordinances.this Chapter 2,the'provisions of Chapter 3
4m, al • � lf applicable)and the other applicable provisions of this manual.
While the guidelines set forth here are intended to be as comprehensive as possible,no printed document can
substitute for the knowledge and experience of a qualified urban forester. The recommendations of the City
Urban Forester may differ from a simple"face value" interpretation of these guidelines;however,the Forester
should work cooperatively with the applicant and with City building officials to reach a mutually agreeable
solution. The Forester should also be prepared to justify"non-standard"decisions by presenting the special
circumstances that apply.
The process of Tree evaluation and site planning will include:
o The identification of all Trees 6"diameter and larger;
o An assessment of minimum standards for Tree preservation;
o An analysis of design constraints and alternatives;and
o The negotiation of mitigative measures when necessary.
2.1 TREE EVALUATION
The City's ordinances address the preservation of Trees 6"diameter and larger. However,not all 6"diameter
and larger Trees have the same value,due to such factors as species or condition. Conversely,some smaller
trees may have greater value due to their rarity,screening potential or other factors.
2.1.1 Tree Evaluation Method
The following factors must all be considered in determining the value of any tree. Weighing factors are
included to aid in this determination.
Using these criteria,a designer can walk the project area and perform a rough analysis of the tree situation
before starting the design of the project. The Urban Forester should use these same factors in approving the
Tree Disposition Conditions.
Ten factors are included:condition,type,size,aesthetics,energy conservation and heat abatement,safety,
adjacent Trees,water quality protection and soil conservation,wildlife habitat and historic significance.
CRITERIA MANUAL (August 15, 2007) Page CM--6
• •
The sum of scores for all ten factors determines the relative value of a Tree. In general,Highly Valued Trees
(total rating of 30 or more out of a possible 40)should be preserved if at all possible. In all cases,the initial
calculation of replacement inches required will depend on the valuation and size of the Tree being removed.
2.1.2 Condition
In assessing a Tree's condition,the forester considers trunk condition,growth rate,tree structure,insect and
disease problems,crown development and life expectancy. A score is assigned as follows:
1 =Poor
2=Fair
3=Good
4=Excellent
2.1.3 Type
The species of Trees found in the City have been divided into four classes based on overall quality. The chart in
Appendix A indicates how each species fits in this general classification. A score is assigned as follows:
1 =Class IV
2=Class III
3 =Class II
4=Class I
2.1.4 Size
Tree sizes are divided into four categories. A score is assigned for each size category as follows:
1 =Less than 8 inches diameter
2=Between 8 inches and 16 inches diameter
3 =Between 16 inches and 25 inches diameter
4=More than 25 inches diameter
2.1.5 Screening;Aesthetics
Trees may score high in this area if they provide screening and privacy to the property or if they are in good
condition and have exemplary form. A score is assigned as follows:
1 =Poor
2=Fair
3 =Good
4=Excellent
CRITERIA MANUAL (August 15,2007) Page CM--7
s •
2.1.6 Enemy Conservation and Heat Abatement
If a Tree is shading a building or pedestrian use area in its existing situation,it receives a high score under this
category. The energy conservation and heat abatement potential is also considered even if there are not obvious
benefits,since trees in general cool the air. For example,large Trees west of a buildable area will score high. A
score is assigned as follows:
1 =Poor
2=Fair
3 =Good
4=Excellent
2.1.7 Safety
If a Tree is in a hazardous situation due to external factors related to man-made features(not inherent in the
condition of the Tree),for example,its location relative to a road intersection,etc.,it receives a low score.
Scores reflect the feasibility of mitigating the safety problems and are assigned as follows:
1 =Hazardous;low mitigation potential
2=Hazardous;medium mitigation potential
3=Hazardous;high mitigation potential
4=Not hazardous
2.1.8 Adjacent Trees
The proximity of other Trees has a bearing on a Tree's value. Everything else being equal,a lone Tree has
greater value than one Tree of many. The fate of other Trees in the vicinity also affects this rating factor. A
score is assigned as follows:
1 =Many Trees;high retention potential of adjacent Trees
2=Many Trees;low retention potential of adjacent Trees
3=Few adjacent Trees
4=Lone Tree
2.1.9 Water Quality Protection and Soil Conservation
Trees help reduce storm water runoff and enhance ground water recharge by breaking the impact of raindrops
and improving soil structure. A Tree's effectiveness in this capacity is correlated with the size of the crown and
root area. Large Trees with full crowns and unrestricted root areas score highest in this category. A score is
assigned as follows:
1 =Poor
2=Fair
3=Good
4=Excellent
CRITERIA MANUAL (August 15,2007) Page CM--8
• •
2.1.10 Wildlife Habitat
This factor is rated on the basis of the intrinsic value of the type of Tree as a provider of food and forage and
general wildlife cover characteristics,or on the basis of field observations of a particular Tree.
Regarding field observations,an individual Tree may rate higher than the assigned intrinsic value of the genus
due to such things as the presence of food-bearing parasites or epiphytes or due to the potential for or actual
presence of wildlife nesting cavities. A score is assigned as follows:
1 =Poor
2=Fair
3=Good
4=Excellent
2.1.11 Historical significance
The highest rating in this category is reserved for Trees that fit one of the following criteria:
o The Tree is on a registry of historic or especially important Trees.
o The Tree has been documented as historically significant.
o The Tree is rare in the Houston area.
o Due to its location and size,the Tree serves as a significant landmark on the landscape.
Since historical significance is largely a function of age,the Urban Forester's estimate of the age of the Tree
also has a bearing on this value. A score is assigned as follows:
1 =Less than 20 years old.
2=Between 20 and 40 years old.
3=Greater than 40 years old.
4=Registered,rare or landmark tree.
2.2 TREE PRESERVATION CRITERIA
2.2.1 Root Zone Impacts
As more completely described in Chapter 4,most of the important roots are shallower than three feet,so the
Urban Forester will normally require much less protection(or no protection)for subsurface areas deeper than
three feet,even if they are nominally within a CRZ. Boring of utility lines,for example,might have very little
or no impact on tree roots if carried out deeper than three feet.
Because existing development on a site may affect the actual distribution of tree roots,the Urban Forester may
require protection of areas outside the CRZ and may determine that it is not necessary to protect areas within
the CRZ where there may be few,if any,significant roots.For example,a Tree growing next to a house on a
slab will not normally have as many significant roots beneath the slab as the side of the root system growing
without the covering of a non-porous surface. This will allow new buildings to be erected on the site of the old
slab near a Tree to be preserved.
Design constraints often dictate that Trees slated for preservation have some encroachment on their CRZ.
Weighing this fact with what appears to be an acceptable degree of risk to most Trees,the following maximum
allowable impacts have been established for Trees with normal CRZ's:
CRITERIA MANUAL (August 15,2007) Page CM--9
• •
o A minimum of 70%of the CRZ must be preserved at natural grade.
o No cut or fill greater than two(2)inches will be located within the inner 70%of the CRZ.
In order to ensure that root zones are adequately preserved,protective fencing should be erected to enclose areas
with significant roots.Root areas that will be covered with permeable paving must be protected by fencing until
the immediate time for construction of the permeable paving. If this is not possible(due to limited access to the
site),mitigative measures must be taken to protect the roots as much as possible(see Section 3.1.2).
2.2.2 Crown Impacts
The following is the maximum allowable impact for Tree crowns:
o A maximum of 30%of the viable portion of a Tree's crown may be removed.
Construction methods must also be considered. For example,a building wall may only require the removal of
30%of the crown,but the scaffolding necessary to construct the building may require the removal of another
20%of the crown.
2.2.3 Deviations from Criteria
These criteria represent minimum standards for determining whether or not a Tree is "preserved." Greater
impacts may be allowed,provided that all design alternatives have been proven unfeasible and that some
acceptable form of mitigation such as a remedial care program is negotiated(see Section 3.1.1). Conversely,
some cases may require that a larger area of root area be preserved to increase the survival potential of Highly
Valued Trees.
These design criteria are enforced in the field as well as on the plan. Plan adjustments made during construction
must be reviewed and approved by the City Urban Forester prior to the adjustments being made.
2.3 DESIGN CONSTRAINTS AND ALTERNATIVES
In addition to the preservation of valuable Trees,many other factors can affect site planning:reasonable and
lawful use of the property,cut and fill limitations,access and egress restrictions,parking and driveway
requirements,and impervious cover limitations. Tree preservation is intrinsically less definitive than most of
these restrictions,and all factors must be considered together to arrive at a reasonable solution. In some cases it
may be desirable or necessary to remove Trees and replace them with newly planted Trees.
In order to best provide for the preservation of Trees,the project designer should carefully consider different
design alternatives in the initial planning of the project. Meeting with the City Urban Forester in a preliminary
consultation prior to submitting plans for review is advised when there appear to be conflicts.
In the review of a proposed project,the first indicator of how well Trees have been incorporated in the design
process is the impact on Trees larger than 6"diameter. These Trees are considered on an individual basis,and a
proposal to remove any of them is carefully scrutinized.
Another indicator is how the proposal will impact smaller,valuable Trees. These Trees are typically considered
in mass as they relate to the overall preservation of the character of the site.
The following sections describe some design alternatives that can be used to preserve Trees.
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• •
2.3.1 Permeable Paving
This alternative is less preferable than leaving 70%of the root area natural. The qualities that make a good
paving surface are in direct conflict with the qualities necessary to save tree roots. Permeable paving is
permitted,however,provided the installation meets City specifications and the following criteria:
o Finished grade of the permeable paving surface is to be set above existing grade,if necessary to
provide room for base and paving material without unreasonable cutting. Existing grade and new base
material shall not be cement stabilized or otherwise made non permeable. Elevating the paving can be
utilized provided it does not cause significant problems not related to trees(i.e.drainage).
o A minimum of 60%of the CRZ must remain at natural grade.
o The combined area of permeable paving and natural cover around a Tree must be at least 80%of the
CRZ.
o Permeable paving is only permitted in parking spaces and low traffic drives.
2.3.2 Building Alternatives
In many cases Buildings have been erected very close to the Tree with little adverse effect on the Tree.
Construction methods that make this possible include:
o Pier and beam foundations,with sufficient air space to allow oxygen to penetrate into the soil for the
roots.
o Finished floor elevations that minimize cut and fill.
o Buildings notched around significant trees.
o Buildings designed to fit under crowns of adjacent Trees.
To comply with the design criteria requiring retention of 70%of a Tree's crown,consideration must be given to
the following:
o Providing adequate work space during construction;
o Providing a safe distance between limbs and walls,eaves,roofs,etc,;and
o Applying proper pruning techniques.
2.3.3 Sidewalks
Sidewalks appear innocuous on plans,but can be very detrimental to Trees because of grading requirements.
Some design alternatives that should be considered are:
o Move sidewalk as far from Tree trunks as possible.
o Construct sidewalk on grade in the location of the original sidewalk.
o Provide a finished grade above existing grade for sidewalks required in close proximity to a Tree
trunk.
o Route drainage under sidewalks where elevated grade is required.
o Reduce width of sidewalk.
2.3.4 Grading
A grade change of a few inches can be extremely detrimental to a Tree.
Some design alternatives that can be used to preserve Trees are as follows:
CRITERIA MANUAL (August 15, 2007) Page CM--11
• •
o Provide Tree well and/or aeration systems for Trees in fill areas to preserve 70%of CRZ.
o Provide retaining walls to mitigate cuts and fills to preserve 70%of CRZ.
2.3.5 Utilities
Underground water and sewer lines,storm sewers,lawn irrigation systems have significant impact on Trees,as
do overhead electric and telephone utilities. Some typical design alternatives that should be considered are as
follows:
o Establish the trenches for underground utilities where they will have the least impact on Trees.
o Stack underground utility lines to reduce the number of trenches required.
o Bore or tunnel under Trees to minimize root impacts .
o Hand-dig trenches to avoid cutting any roots larger than one(1)inch diameter.
o When planting Trees,plant low-growing Trees under power lines.
3.MITIGATIVE MEASURES AND REPLACEMENT TREES
Many of the existing trees in the City grow very slowly,making preservation very critical to avoid long-term
impacts. At the same time,land is at a premium,and there is considerable pressure to build on as much land as
possible. In many cases,it will be difficult to meet the above minimum standards,in which case,the Urban
Forester may specify that Replacement Trees be planted or that special mitigative measures be taken to protect
existing Trees.
3.1 MITIGATIVE MEASURES
To protect Trees in cases in which it is not possible to meet the minimum design criteria,the Urban Forester
may stipulate mitigative measures. Some of these mitigative measures include:
3.1.1 Tree Maintenance
A remedial care program can increase the survival potential to an acceptable level in many cases. The City
urban forester must review the remedial care program to estimate whether it will accomplish what is necessary
to maintain the viability of affected Trees. Such a program might include schedules for watering,feeding,soil
aeration,spraying,etc.
To ensure compliance,the program must be documented by a plan note at the time of plan approval. In
addition,prior to issuance of a certificate of occupancy,a permittee may be required to submit,in especially
critical cases,the following:
o A signed service contract for review and approval by the City;and
o Fiscal security in an amount equal to the going rate for the approved service plus 15%to cover
administrative costs.
These measures are necessary because the remedial care program must typically extend over a minimum 12-36
month period after completion of the project.
3.1.2 Special Construction Techniques
In conjunction with remedial care,mitigation may include special construction techniques not normally required
in standard specifications. Some of these techniques include the following:
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o Leaving existing sidewalks and driveways in place for storage of materials and vehicular access,until
construction of the Building is complete.
o Prior to excavation within Tree driplines or the removal of Trees adjacent to other trees that are to
remain,make a clean cut between the disturbed and undisturbed root zones by hand or with a trencher
or similar equipment to minimize root damage.
o In significant root areas that cannot be protected during construction with fencing and where vehicular
traffic is anticipated,cover those areas with four(4)inches of organic mulch topped by two-inch thick
by 8 inch wide firmly attached boards to minimize soil compaction and root damage.
o Perform all grading within significant root areas by hand to minimize root damage.
o Water all Trees most heavily impacted by construction activities deeply once a week during periods of
hot,dry weather. Spray Tree crowns with water periodically to reduce dust accumulation on the
leaves.
o When installing concrete adjacent to significant roots of a Tree,use a plastic vapor barrier behind the
concrete to prohibit leaching of lime into the soil.
3.2 REPLACEMENT TREES
The most common measure used to mitigate Tree removals is the planting of Replacement Trees. The
following factors affect tree replacement:
o The quantity of Replacement Trees;
o The available planting area;
o The anticipated rate of survival of Trees planted;
o The types of Trees proposed.
3.2.1 Quantities of Replacement Trees
Replacement Tree values will be expressed in terms of caliper inches(diameter)measured at 6"above natural
grade or planting media.
For Trees with a value greater than 30 points using the criteria in Section 2.1,replacement calculations will
require 100%of the diameter of the Tree in question. For example,a Tree with a 24-inch diameter will require
24 caliper inches of Replacement Trees,which could be met by four Trees of 6 inches each or three Trees of 8
inches each.
For Trees with a value from 20 to 30 points,replacement calculations will require 75%of the diameter of the
Tree in question. In this case,a Tree with a 24-inch diameter will require 18 caliper inches of Replacement
Trees.
For Trees with a value from 10 to 19 points,replacement will require 50%of the diameter of the Tree in
question.
For trees with a value of less than 19 points,and in cases where a Tree is dead or judged by the Urban Forester
to be in such poor condition that it will not live more than another year,no replacement is required.
In all cases a reduction shall be allowed in the number of Replacement Inches,if the applicant requests a
reduction,and if the applicant demonstrates clearly that there are sufficient remaining,pre-existing Trees on the
affected Subject Site to meet 1.5 times the minimum planting standard set forth in Section 3.2.5. A reduction of
10%may be granted if a minimum of at least 1.5 times the MPS exist,20%if a minimum of 2.0 times the MPS
exist,and up to 50%if a minimum of 2.5 time the MPS exist on the subject lot. Notwithstanding the minimum
planting standards,each of the remaining pre-existing trees must be Class I or II trees six inches or more in
diameter.
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3.2.2 Available Planting Area: On-site and off-site Replacement
Replacement Trees should be planted on the Subject Site from which existing trees are to be removed. If this is
not feasible,the applicant may either:
o Initiate a proposal to plant Trees off-site if the planting site is in reasonable proximity(within 1,000
liner feet)to the project area,or on public areas within the City of West University Place,or on public
areas commonly used by residents of West University Place immediately adjacent to the City.
o Provide for Replacement Trees through a"replacement inch" certificate from a Tree Trust or Urban
Forestry Enhancement Fund.
3.2.3 Survival Potential;Irrigation and Maintenance
Before approving any replacement option,the Urban Forester will assess the probability that Trees planted will
survive. This will require trees of high quality from a reputable nursery. Trees planted with tree spade or ball
and burlap method must have a root ball that has a diameter of at least 12"for each diameter inch of tree trunk.
Container trees must meet the most current standard of the American National Standards Institute Z 60.1. Tree
survival typically requires that some type of irrigation and maintenance capability be implemented for a
minimum of 12 months. Irrigation or maintenance may not be required for the full 12 months if it can be
adequately demonstrated that,given the size and type of Trees planted,the planting site and the time of year the
Trees are planted,the mortality rate is likely to be low. The applicant may be required to conform to the
maintenance guidelines set forth in 3.1.1.Tree Maintenance.
3.2.4 Types of Replacement Trees
In order to enhance the general quality of the urban forest,75%of the Replacement Trees required must
normally be Class I or Class II species(see Appendix A).
3.2.5 Minimum Standards For Total Number of Trees
Regardless of the number of Trees present on a Subject Site before development or construction,each Subject
Site must attain the Minimum Planting Standard whenever there is Major Development. This standard has been
determined by the City as a reasonable expectation for property within the City,given current open space and
setback requirements. To satisfy the Minimum Planting Standard requirement,a Tree must be at least six
inches in diameter measured 6 inches above the ground. Pre-existing Trees may be of any species,while Trees
planted to meet the Minimum Planting Standard requirement must be Class I or Class II Trees as set forth in this
Criteria Manual. The number of Trees required depends on the size of the affected Building Site and is set forth
in the following table:
CRITERIA MANUAL (August 15,2007) Page CM--14
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Size of Building Site in square feet Number of Trees required
5,000 or less 2
5,001 to 7,500 3
7,501 to 10,000 4
10,001 to 12,500 5
12,501 to 15,000 6
15,001 or more 7
3.2.6 Enforcement Criteria;Delayed Plantings.
The location,size and type of all Replacement Trees and all Trees planted to attain the Minimum Planting
Standard must be shown or referenced on a site plan in a manner which will allow verification of their
installation at the time of inspection for certificate of occupancy.
Optimum planting times do not always correspond to project completion. For that reason,planting of
Replacement Trees and Trees planted to attain the Minimum Planting Standard may take place after a certificate
of occupancy is issued,if approved by the Urban Forester,and if: (i)the permittee posts fiscal security in an
amount equal to the going rate for installed Trees with a one-year guarantee,plus 15%to cover administrative
costs,together with all necessary rights of entry,(ii)the permittee provides a"post-dated" replacement inch
certificate to guarantee planting at a specified future date if the permittee fails to provide the required Trees by
that date,and such a certificate can be made returnable to the permittee in case the permittee provides the
required Trees,or(iii)the permittee provides other sufficient assurance that the Trees will be provided.
Certificates of occupancy may be issued conditionally in this case.
b 14:\o 1472man.54
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S •
APPENDIX A: CLASSES OF TREES
Trees are divided into four classes.Class one and two trees are considered the most valuable in enhancing the
environment and are the most likely to prosper in this area.Trees in Class 1 and 2 are considered qualified trees.
Qualified trees are Class 1 and 2 trees with a minimum of 6 inches diameter. The trunk is measured 6"above
the ground.
For every 15"of replacement inches required the applicant must plant at least one 8"diameter tree of species
class 1. For example;if the replacement inches is 37"diameter,the applicant must plant at least 2(two)8"
diameter trees of species class 1 and remaining inches can be qualified trees(min 6"diameter). The total inches
planted would still have to be equal to or more than the required 37"diameter.
Class 1 trees
Live Oak Quercus virginiana
Shumard Oak Quercus shumardii
Nuttall Oak Quercus
Water Oak Quercus
Bur Oak Quercus
White Oak Quercus
Swamp Chestnut Oak Quercus
Polymorpha Oak Quercus
Chinquapin Oak Quercus
Winged Elm
Cedar Elm
Drummond Red Maple
Baldcypress
Montezuma Cypress
Southern Magnolia
Little Gem Magnolia
Mexican Sycamore
Class 2 trees
White Ash
Green Ash
Pecan
Hickory species
Lacebark Elm
Black Walnut
Holly species(tree form)
Sweetgum
Chinese Pistache
Texas Persimmon
River Birch
American Elm
American Sycamore
Class 3 trees
Any species not included in Class 1,2,or 4
Class 4 trees
Chinese Tallow
Sugarberry(Hackberry)
Silver Maple
Arizona Ash
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Chinaberry
Camphor
***Donation to the Tree Trust or UFEF are now$125 per inch. Each 6 inch diameter tree purchased in the Tree
Trust or UFEF cost$1,800.00,and each 8 inch tree purchased in the Tree Trust or UFEF cost$2,100.00.
APPENDIX B. WARNING SIGN REQUIRED FOR TREE PROTECTION FENCES
Each warning sign must be weatherproof and printed in black on a white background at least 8.5 x 11 inches in size,
except for the two lines indicated by "*", which must be red. The print shall be at least as large as shown below.
The phone numbers shall be filled-in with the current phone numbers supplied by the Urban Forester.
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• •
TREE PROTECTION
FENCING
required by Code of Ordinances
City of West University Place
DO NOT REMOVE !
FINE: $100 OR MORE. JOB MAY BE SHUT DOWN. FOR
PERMISSION FOR TEMPORARY REMOVAL, CALL
. TO REPORT VIOLATIONS, CALL
CERCAS PARA PROTECCION
de A
Require por Ordenaciones de la
Ciudad de West University Place
FAVOR DE NO REMOVER*
MULTA DE: $100. 0 MAS. TRABAJO PUEDE SER
TERMINAD0. PARA PERMISO TEMPORAL DE REMOVER
LLAME: . PARA REPORTAR VIOLACIONES
LLAME:
CRITERIA MANUAL (February 28, 1994) Page CM--18