Chapter 8.60
CITY OF MILLBRAE TREE PROTECTION AND URBAN FORESTRY PROGRAM
Sections:
8.60.050 Standards and licensing.
8.60.070 Property owner’s responsibility for street trees.
8.60.090 Permit review and decision.
8.60.110 Preservation and maintenance of protected trees.
8.60.120 Tree protection measures.
8.60.140 Designated administrative responsibilities.
8.60.150 Maintenance of street trees by public utilities.
8.60.160 Emergency work on protected trees.
8.60.170 Penalties for violation.
Prior legislation: Ords. 598, 680, 1976 Code §§ 8-12.01 through 8-12.18.
8.60.010 Title.
This chapter shall be known as the city of Millbrae tree protection and urban forestry program. (Ord. 814, § 1).
8.60.020 Findings.
Trees and the urban forest provide a variety of important benefits in the urban environment, including removing carbon from the atmosphere, reducing energy use, improving air quality, reducing respiratory illness, noise and stress reduction, moderating stormwater flows, reducing the urban heat island effect and heat-related illnesses, protecting water quality, improving economic sustainability, and providing habitat for wildlife. In addition to the health benefits realized through the protection and promotion of the environment, trees and urban forests also support the physical and mental health of residents. (Ord. 814, § 1).
8.60.030 Purposes and intent.
This chapter establishes policies, regulations and standards necessary to ensure the city will continue to realize the benefits provided by its urban forest. The purposes of this chapter are to:
A. Establish and maintain the maximum amount of tree cover in the city;
B. Maintain public and private trees in a healthy and nonhazardous condition through good arboricultural practices and community education programs;
C. Establish and maintain appropriate diversity in tree species and age classes to provide a stable and sustainable urban forest;
D. Promote and maintain the value of property;
E. Support and implement the goals and objectives of the climate action plan; and
F. Promote and maintain the aesthetic value of the community generally. (Ord. 814, § 1).
8.60.040 Definitions.
For the purposes of this chapter, the following words shall have the meaning ascribed to them in this section:
A. “Alter” means to take action by cutting or pruning any tree, or by filling, surfacing, grading, excavating, compacting or changing the drainage pattern of the soil around any tree in a manner that threatens to diminish the vigor or structural stability of the tree.
B. “Applicant” means a property owner who has submitted an application to the city for a permit to undertake work authorized by this chapter on a protected tree.
C. “Arborist” or “certified arborist” means an individual in the profession of arboriculture who, through experience, education, and related training, possesses the competence to provide a tree report, tree survey or supervise the care and maintenance of trees; and who is certified by the International Society of Arboriculture (ISA), a member of the American Society of Consulting Arborists, or another nationally recognized tree research, care, and preservation organization approved by the city.
D. “Canopy dripline” or “dripline” means the diameter of the tree measured from the outermost leaves on one side to the outermost leaves on the opposite side.
E. “Construction activity” means any construction work associated with or requiring a permit for any new building, building addition, building demolition, grading, trenching, excavation or paving. This includes all necessary related activities which may or may not be shown on site plans, including, but not limited to: storing/staging of materials, site access, parking, placement of temporary structures, debris disposal, additional excavation and landscaping.
F. “Contractor” means any person or business performing work on a protected tree holding a valid tree and palm contractor’s license (C-49) from the state of California.
G. “Diameter” means measurement of the trunk diameter which, for the purpose of applying this chapter, shall be made four and one-half feet (fifty-four inches) above natural grade. Measurement of multi-trunked trees shall be determined by the sum of all trunk diameters measured at four and one-half feet (fifty-four inches) above natural grade.
H. “Heritage tree” means a protected tree or grouping of trees designated by resolution of the city council, that possess exceptional aesthetic, biological, cultural, or historic value and is expected to have a continuing contribution to the community.
I. “Parking strip” includes the area between the curb or curb and gutter and the sidewalk and includes all planting and landscaping treatments therein.
J. “Person” means any individual, firm, association or corporation, and any agent, employee or representative thereof.
K. “Pollarding” means a semiformal pruning system that maintains crown size by initial heading back of branches on young trees or young portions of older trees, followed by removal of arising sprouts back to their points of origin, at appropriate pruning intervals, without disturbing the pollard head.
L. “Property owner” means the person who owns the property where a tree is or may be placed.
M. “Protected tree” means any qualified significant tree or heritage tree, as defined and identified in this chapter, located on public or private property.
N. “Pruning” means the removal of one-fourth or more than one-fourth of the above ground mass of the tree or one-fourth or more than one-fourth of the root system.
O. “Removal” means any of the following: (1) complete removal, such as cutting to the ground or extraction, of a protected tree or one of its multi-trunks; (2) taking any action foreseeably leading to the death of a tree or permanent damage to its health; including but not limited to severe pruning, cutting, girdling, poisoning, overwatering, unauthorized relocation or transplanting of a tree, or trenching, excavating, altering the grade, or paving within the dripline area of a tree; (3) damaging the canopy or root system of a tree to a degree that has been determined in writing by a certified arborist to have caused irreversible decline/death of the tree.
P. “Significant tree” means a type of protected tree as defined in this chapter.
Q. “Street” is the area dedicated to the city containing any and all of the following: the roadway, median islands, gutters, curbs, parking strips, sidewalks and any property adjacent to the sidewalk, improved or unimproved, included as part of the total width of property dedicated or otherwise conveyed to the city for the purpose of constructing the street. The area adjacent to the sidewalk is often an extension of front or side yards, varies from location to location, and its boundary is not readily distinguishable. The boundary can be determined by contacting the public works department, engineering division.
R. “Street tree” means any tree located in the public right-of-way and on public lands.
S. “Tree” means a woody perennial plant characterized by having a main stem or trunk or a multi-stemmed trunk system with a more or less definitely formed crown and which is usually over ten feet high at maturity.
T. “Tree plan” means a scaled site plan with supporting documentation that identifies the location, type and placement of tree species on a project site and contains information that includes the location of underground and overhead utility locations and regulates the care and maintenance of trees.
U. “Tree protection zone (TPZ)” means the protected area located around the tree one and one-half times the diameter of the canopy dripline, or as otherwise specified by a certified arborist and approved by the city.
V. “Tree topping” or “topping” means tree size reduction by heading back large, live branches, using pruning cuts at internodal locations along the stems, without regard to long-term tree health or structural integrity.
W. “Trimming” means the cutting or removal of a portion of a tree which removes less than one-fourth of the crown or existing foliage of a tree, removes less than one-fourth of the root system, and does not kill the tree.
X. “Trunk” means the single main stem or multiple stems arising from a common root system at grade. Stems arising separately at grade elevation shall be considered separate tree specimens.
Y. “Yard” means all land on a lot not occupied by a building.
1. “Front yard” means a yard extending across the full width of the front of the lot between its front lot line and any portion of the front facade of the main building.
2. “Rear yard” means a yard extending across the full width of the back of the lot between its rear lot line and any portion of the rear facade of the main building.
3. “Side yard” means a yard between the side lot line of the lot and any portion of the side facade of the main building and extending from the front yard of the lot to the rear yard of the lot. (Ord. 814, § 1).
8.60.050 Standards and licensing.
A. Any person or business performing work on a protected tree in Millbrae for compensation must hold a valid tree service contractor’s license from the state of California (C49 tree and palm contractor);
B. All tree work conducted in the city must comply with the American National Standards Institute (ANSI) A300 tree care standards. (Ord. 814, § 1).
8.60.060 Protected trees.
A. Heritage Trees. The city council may declare by resolution any tree to be a heritage tree for special recognition if said tree is healthy and has adapted well to the climatic conditions of the area, if said tree is visually accessible from a public right-of-way and if the city council finds that the tree is of exceptional significance with respect to history, size, location, species, or age.
B. Significant Trees. Significant trees include the following:
1. A tree of any species measuring ten inches diameter (31.4 inches circumference) or more, when measured at fifty-four inches above natural grade, except those tree species identified as exempt under this section.
2. Any tree designated for protection through the approval of a planning entitlement application.
3. Any replacement mitigation tree or other tree designated to be planted due to the conditions listed in a project approval.
4. Any tree designated for carbon sequestration and storage and/or environmental mitigation purposes as identified in an agreement between the property owner and a responsible government agency or recorded as a deed restriction.
C. Exempt Trees. The following trees may not be classified as significant trees or designated as heritage trees, regardless of size:
1. Acacia genera;
2. Broadleaf privet (Ligustrum lucidum);
3. Fruit trees of any kind;
4. Monocot trees including palm trees;
5. Russian olive (Elaeagnus angustifolia);
6. Tasmanian blue gum (Eucalyptus globulus);
7. Tree of Heaven (Ailianthus altissima);
8. Tulip tree (Liriodendron tulipifera). (Ord. 814, § 1).
8.60.070 Property owner’s responsibility for street trees.
The city has ownership and control of all street trees now or hereafter in any street and public right-of-way, including parking strips within the city limits, but the adjacent property owner is responsible for the care and maintenance of such trees.
It is the duty and responsibility of all property owners to maintain street trees within parking strips fronting upon or abutting said owner’s property in a safe and healthy condition. This maintenance must include watering as needed and keeping such strips free from weeds or any obstructions contrary to public safety. Nothing in this chapter may be deemed to impose any liability for injury or damages or a duty of care or maintenance upon the city or upon any of its officers or employees. (Ord. 814, § 1).
8.60.080 Tree permits.
Any property owner desiring to perform any work on or alter in any manner a protected tree on their property or a protected tree within the public right-of-way adjacent to their property must apply to the city for a tree permit. Permits to perform work on all trees within the public right-of-way must be accompanied by a concurrent encroachment permit from the public works department. An application for a tree permit is required for the following:
A. Tree Pruning. An application to prune a protected tree must include a description of the proposed work or alteration, the reasons, and the identification and contact information of the licensed contractor and date(s) of work to be performed.
B. Tree Removal. In addition to the requirements for tree pruning, an application to remove a protected tree must include an arborist report prepared by a certified arborist detailing the location, health rating, structural rating, and overall condition rating of the tree to be removed, evidence supporting its removal, and measures to restore the area once the tree or trees are removed. A report or statement from a licensed tree service contractor may be substituted for an arborist report for protected trees with a trunk diameter less than eighteen inches measured at fifty-four inches above natural grade.
C. Tree Relocation. In addition to the requirements for tree pruning, an application to relocate a protected tree must include the following:
1. Plans identifying the origin, path, and destination of the relocated tree.
2. An arborist’s report prepared by a certified arborist. The report must include a risk assessment and safety measures to be taken during the relocation.
3. Relocation of protected trees within the public right-of-way must be accompanied by a concurrent encroachment permit from the public works department.
D. Construction Activities Within a Tree Protection Zone. Trenching, grading and excavation within the tree protection zone (TPZ) of protected trees should be avoided to the greatest extent possible. When trenching, grading or excavation is necessary within the tree protection zone, the application must identify the location and extent of all work to be performed and identify tree and root protection efforts. No concrete, pavers or asphalt paving may be placed within the tree protection zone of a protected tree without prior approval of a tree permit unless identified and approved through a separate permit. All ground disturbing activity within a tree protection zone must be done under the direction of a certified arborist.
E. Planting. Trees of an approved species may be planted in parking strips and other right-of-way frontage by the responsible adjacent property owner after obtaining a tree permit from the city. (Ord. 814, § 1).
8.60.090 Permit review and decision.
A. Each application for a tree permit will be reviewed by the city to determine if the proposal is consistent with the provisions of this chapter. In addition to those factors, the city will review each application to determine whether the proposed work (1) will create, continue or aggravate any hazardous condition or public nuisance; (2) will prevent or interfere with the growth, location or planting of street trees; and (3) is otherwise consistent with the standards and regulations set forth herein and in any adopted plans.
B. The city will consider the condition of the tree with respect to disease, danger of falling, proximity to existing or proposed structures, and interference with utility facilities and services.
C. Tree permits for significant trees will be reviewed and approved by city staff.
D. Tree permits for heritage trees will be referred to the planning commission for approval.
E. Tree permits will be effective for a period of forty-five days from the date that the permit decision becomes final and conclusive unless additional time is specified in the permit approval.
F. The issuance of a permit pursuant to this chapter may not create any liability of the city with regard to the work to be performed, and the applicant for such permit must hold harmless the city, its officers and employees from any damage or injury that may occur in connection with or resulting from such work. (Ord. 814, § 1).
8.60.100 Appeal process.
A. Any person may appeal a tree permit to remove or relocate a protected tree to the planning commission by filing an appeal in writing with the community development department no later than close of business on the tenth calendar day after the date the decision on the permit was issued. The city must provide notice by mail of the date, time, and place of the meeting to the appellant and the applicant at least five days prior thereto.
B. The tree permit becomes final and conclusive on the eleventh calendar day following the date of the decision if no appeal is filed as specified above.
C. Removal or relocation of a protected tree authorized by permit must not commence during the ten-day appeal period. If an appeal is filed, no work on a protected tree authorized by permit may commence until the complete appeal process has concluded pursuant to this section. The planning commission may affirm, revise or modify the permit or remand the matter back to city staff for further investigation and resolution.
D. Any final action of the planning commission may be appealed to the city council by any person, provided such appeal is submitted within ten days of the planning commission action with the city clerk, accompanied by a fee set by the city council. (Ord. 814, § 1).
8.60.110 Preservation and maintenance of protected trees.
A. Property owners are responsible for the preservation and maintenance of protected trees located within their property and their adjacent right-of-way frontage including parking strips.
B. No protected tree may be removed, pruned, or otherwise materially altered without a permit, except as provided in this chapter. Routine and incidental trimming to maintain a protected tree in a healthy condition does not require a permit.
C. Pruning. Pruning a protected tree must be in accordance with the following standards and methods:
1. All pruning must be done in accordance with the most current version of the American National Standards Institute ANSI A300 tree care standards;
2. Removal of low-hanging branches, the existence of which interferes with visibility on, free use of, or access to any portion of any street, including sidewalks;
3. Crown thinning, crown cleaning and the selective removal of branches, not to exceed thirty-three percent of the tree area, specifically for the purpose of increasing light penetration and air circulation within the crown, unless otherwise recommended by a certified arborist;
4. Removal of any deadwood; and
5. Maintenance of trunk and main lateral branches as well as the symmetrical appearance or natural shape of the tree.
The city may authorize by permit pruning standards and methods that exceed the restrictions specified above if the application presents unusual or justifiable circumstances warranting such an exception. Such circumstances may include particular conditions or qualities related to the street tree or the neighborhood, including consideration of the preservation of unique neighborhood characteristics.
D. Removal. No removal of a protected tree may be authorized without prior approval of a tree permit. Removal of a protected tree must not have an adverse effect on erosion, soil retention and diversion or increased flow of surface waters as a result of the tree removal. In granting approval of a tree permit to remove a protected tree, one or more of the following findings authorizing removal must be made by the decision-making authority:
1. The protected tree is dead or likely to promote the spread of insects or disease.
2. The protected tree’s roots are interfering with sewer or other utility lines or are damaging sidewalks in cases in which other mitigation methods are not reasonably feasible.
3. Removal of the protected tree is necessary to protect the public health, safety and welfare.
4. Removal of the protected tree complies with an approved mitigation measure under the California Environmental Quality Act.
5. Removal of the protected tree is necessary for the operation of active or passive solar facilities and relocation is not feasible.
6. Removal of the protected tree is necessary for a development project authorized by another permit approved by the city.
If a tree removal is permitted, the owners of adjacent property must be notified of the authorized tree removal and the reasons therefor.
E. Mitigation for Tree Removal. Any protected tree that is removed, whether authorized or in violation of this chapter, must be mitigated with either replacement trees, payment into an in-lieu tree replacement fund, or a combination of both, as determined below. Trees must be replaced with the same tree species unless it is determined that another species would be more suitable for the location. The city has final authority on the species, location, and number of replacement trees in the public right-of-way. Exempt trees may not be used as replacement trees.
1. Tree Replacement Calculation. The diameter of each protected tree to be removed from the site must be measured at fifty-four inches above natural grade to determine size in inches.
a. Removed significant trees with a diameter less than eighteen inches must be replaced at a 2:1 ratio with a tree box diameter of twenty-four inches and having a minimum caliper of one and a half inches.
b. Removed significant trees with a diameter between eighteen inches and twenty-four inches must be replaced at a 3:1 ratio with a tree box diameter of twenty-four inches and having a minimum caliper of one and a half inches.
c. Removed significant trees with a diameter greater than twenty-four inches must be replaced at a 4:1 ratio with replacement tree box diameter of twenty-four inches and having a minimum caliper of one and a half inches each, or replaced at a 1:1 ratio using a replacement tree box diameter of forty-eight inches and having a minimum caliper of three and a half inches.
d. Removed heritage trees must be mitigated through payment of an in-lieu fee. The planning commission may authorize an alternate replacement measure in those circumstances where a certified arborist has determined the removal of a heritage tree is necessary for public health and safety purposes due to the natural and irreversible decline and death of the tree.
2. In-Lieu Fee Tree Replacement and Valuation Methodology. When installation of a replacement tree is not feasible, protected trees must be replaced with an in-lieu payment into the city’s tree replacement fund. The value of the protected tree must be determined by a certified arborist using the most recent edition of the “Guide for Plant Appraisal” published by the International Society of Arboriculture. The amount of the in-lieu fee must be equal to the value of the protected tree.
3. Combination of Replacement Trees and In-Lieu Fees. A reduced in-lieu fee may be assessed when paid in combination with a reduced number of replacement trees as required in this section.
4. Replacement trees may be authorized for planting in off-site locations with approval of the city and the underlying property owner. (Ord. 814, § 1).
8.60.120 Tree protection measures.
A. Paints, solvents and other chemicals, tools, and construction supplies or materials of any kind are prohibited from being stored within the tree protection zone of protected trees.
B. Signs, metal wires, reflective markers, or similar devices may not be attached to protected trees.
C. Encroachments Into a Tree Protection Zone. If a proposed development, including any site work for the development, encroaches within the tree protection zone of a protected tree, arboriculture best management practices (BMP) outlined in ANSI A300 must be implemented to allow for protection of and preservation of the tree and root system.
D. Underground Trenching. Trenching within the tree protection zone of protected trees must be avoided to the greatest extent possible and may only be done under the direction of a certified arborist and with approval by the city.
1. Underground trenching shall avoid damaging or removing anchor roots and absorbing tree roots of protected trees, avoiding severance of any woody root measuring one-inch diameter or greater, within twenty-five feet of a tree.
2. If root damage avoidance using standard trenching methods is impractical, directional bore or other “trenchless technology” alternative techniques must be utilized to tunnel at least twenty-four inches or more below grade elevation, or at an elevation specified by a certified arborist.
3. Where allowable, trenches must be consolidated into “joint trench” alignments to service as many units as possible.
E. Soil Compaction. No compaction of the soil within the tree protection zone (TPZ) of protected trees may occur above eighty-five percent Proctor compaction rate, unless specifically authorized in writing by the city. (Ord. 814, § 1).
8.60.130 Prohibitions.
It is a violation of this chapter for any person to:
A. Abuse, destroy or mutilate any protected tree;
B. Attach or place any rope, wire (other than one used to support a young or broken tree), sign, poster, handbill or other things to or on any protected tree;
C. Allow or cause to allow any harmful gaseous, liquid or solid substance to come in contact with the roots, trunks or leaves of a protected tree;
D. Allow or cause to allow soil erosion around the roots of a protected tree;
E. Allow or cause to allow root damage from a protected tree to a retaining wall;
F. Prune, plant, remove, alter or undertake any work on a protected tree without a permit or in a manner that violates a permit issued by the city;
G. Refuse or neglect to replace a protected tree or street tree that has been removed, or fail to pay an in-lieu payment into the city’s tree replacement fund;
H. Pollarding of any street tree;
I. Topping of any protected tree or any tree located on public property. (Ord. 814, § 1).
8.60.140 Designated administrative responsibilities.
The community development and public works directors have the authority and responsibility to administer and enforce the provisions of this chapter. (Ord. 814, § 1).
8.60.150 Maintenance of street trees by public utilities.
Public utility companies subject to the jurisdiction of the California Public Utilities Commission may perform pruning or other alteration of street trees, as is necessary, to comply with the safety regulations of said commission and to maintain the safe operation of their facilities. On an annual basis, such companies shall obtain a permit from the city and they shall notify the public works department at least three working days prior to undertaking any such pruning or other work on a street tree, except in cases of emergency. The city shall cause such pruning work to be inspected, when appropriate, to ensure that the pruning practices and procedures as referenced in this chapter and in the city’s adopted plans are followed. The city shall have the authority to stop any tree pruning or other work performed by a public utility company if such practices are not being followed. (Ord. 814, § 1).
8.60.160 Emergency work on protected trees.
A protected tree may be removed or pruned without a permit where it presents an imminent danger to life, property, utilities or essential transportation systems. In such event, the property owner or representative are responsible for the following:
A. Notify the public works department during business hours or the police department after business hours and request authorization of the proposed emergency action, including removal or pruning.
B. Emergency action may be authorized by the city manager, community development director, public works director, chief building official, or their designees, or a member of the police or fire department when the situation and conditions warrant immediate action to protect life or property and other city officials are unavailable.
C. No later than seventy-two hours after the emergency action has been taken, the property owner must apply for an emergency tree permit, submit photo documentation and provide written verification to the city confirming the emergency condition and describing the action taken.
If the city determines that the condition was not reasonably determined to have been an emergency requiring immediate action, the person responsible for removing or damaging the protected tree will be subject to fines and penalties as set forth herein and in Chapter 1.05 MMC. (Ord. 814, § 1).
8.60.170 Penalties for violation.
The penalties for violations of any provisions of this chapter are set forth in Chapter 1.05 MMC. (Ord. 814, § 1).