Trees for Terrace
Trees are important to Mountlake Terrace, and they provide many benefits to the community such as:
- Air quality and oxygen production
- Water quality and flow control
- Soil health and stabilization
- Biodiversity and habitat
- Higher property values
- Shade and temperature regulation
- Climate resiliency
- Increase in visits to local businesses
Learn more about the benefits of trees and see a map of the 100 street trees planted in 2023 by clicking HERE.
Update: Changes to city code regarding trees
At the December 21 meeting, City Council approved an update to Mountlake Terrace's Municipal Code (MTMC). Reference Ordinance no. 2838 (Tree Code Amendment).
Updates to the code include:
- Establishing a Heritage Tree Program
- New Definitions
- Tree Retention Requirements
- Tree Protection Standards
- Replacement of Viable Significant Trees
- Establishing a Tree Fund
- Violations, Enforcement, and Penalties
New Tree Code is effective March 27, 2024
For more information about the updates, click through the tabs below.
Who can apply? On private property, only the property owner. On public property, anyone can apply for heritage tree status.
Criteria. The nominated tree must be at least 36 inches diameter at 4.5 feet from surface of the ground and must have another characteristic that makes the tree special and worthy of heritage tree status (distinctive size, shape, species, historical significance, and/or age.)
Arborist report. A report on the tree by a qualified arborist must be submitted with the heritage tree application. The report identifies the tree’s characteristics, current condition, and current/anticipated maintenance needs. The cost for this report is anticipated to range between $200 and $600 per tree.
How to apply. Application is through the city’s permit portal. Submittal must include contact information, information on how tree meets criteria, a photograph, and a map locating the tree on the property. One heritage tree application may cover more than one tree within one parcel or in one location. The 2024 cost for a heritage tree application is $155, to cover staff review time.
Process. Heritage tree nominations shall be submitted to the city and reviewed for completeness and consistency. Complete applications for public property are referred to the city department director responsible for the property. Private property applications are reviewed by the Community & Economic Development (CED) Department. Next, the Tree Board reviews the application and makes a recommendation to the CED Director to approve or deny the application. The CED Director will make the final determination. Applicants may appeal heritage tree decisions to the Hearing Examiner.
Recording requirements for heritage trees. Snohomish County official documentation tied to the property is required to protect the heritage tree when property ownership changes. The 2024 cost for a recorded document by the Snohomish County Auditor’s Office is $303.50 for a standard recorded document and $1 for each additional page. Document format requirements apply.
Fees for application, arborist report, and recording fees are the responsibility of the applicant.
Heritage tree plaque and mapping. Once the heritage tree review process is complete and the heritage tree has been approved, the city will provide a heritage tree plaque with the tree’s species and a unique identifier, at no cost to the applicant. The city will add the heritage tree to an online map on the city website.
Maintenance. Property owners are responsible for maintaining heritage trees on private property. For public property, heritage tree maintenance will be completed by the city department with responsibility for the property.
Removal of heritage tree designation. Heritage trees may only be removed by meeting one or more criteria listed below, obtaining written approval through the city’s permit portal, and providing notification to the city’s Tree Board. Heritage tree designation may be removed if:
- Retention of the tree would make reasonable use of the property allowed under the current zoning impractical;
- The tree interferes with the needed location of proposed improvements or structures; or
- The tree becomes hazardous and poses a threat to the health, safety, or welfare of the public. (Under this circumstance, emergency tree removal is allowed.)
Grove means 5 or more viable significant trees forming a contiguous canopy.
Heritage tree is a viable significant tree of greater than 36-inch diameter DBH, of distinctive size, shape, historical significance, species, and/or age.
Qualified arborist means an individual with relevant education and training in arboriculture or urban forestry, having one or more of the following credentials:
- International Society of Arboriculture (ISA) Certified Arborist;
- Tree Risk Assessor Qualification (TRAQ) as established by the ISA (or equivalent);
- American Society of Consulting Arborists (ASCA) registered Consulting Arborist;
- Society of American Foresters (SAF) Certified Forester for Forest Management Plans; and
- Board Certified Master Arborist as established by the ISA.
A qualified arborist must have the TRAQ or equivalent qualification to submit tree risk assessment reports related to hazard tree removal.
Significant tree means any tree having a trunk diameter of six inches or greater as measured at DBH for deciduous trees, or at least 7 feet in height for coniferous trees, excluding trees on the City’s posted Prohibited Tree List.
Tree Protection Zone (TPZ) is a defined area within and including an outer boundary, as determined by a qualified professional arborist, in which certain activities are prohibited or restricted to prevent or minimize potential impacts from construction or development to individual trees or groups of tree trunks, roots and soil. The TPZ is variable depending on species, age and health of the tree, soil conditions and proposed construction. TPZ denotes the location of tree protection fencing.
Viable tree means a significant tree that a qualified arborist has determined to be in fair or good health, with a low risk of failure due to structural defects over the next 12 months.
For any site proposed to be developed or cleared containing significant trees, at least twenty-five percent (25%) of the viable significant trees must be retained. If this tree retention requirements is met, no further action is required. When 25% tree retention cannot be met, a combination of (1) tree retention, (2) tree replacement above and beyond City landscaping requirements for site development, and/or (3) tree fee-in- lieu must be used to mitigate the impacts of all significant viable trees removed from the site.
Exceptions. The CED Department may allow a reduction in the minimum significant tree retention percentage to facilitate preservation of a greater number of smaller trees, a cluster or grove of trees, or contiguous perimeter buffers.
Frontage improvements. Significant trees that must be removed to accommodate the installation of a required frontage improvement shall not be included in the calculation of the minimum retention percentage for the site.
Incentives for higher levels of tree protection. The CED Department may grant reductions or adjustments to other site development standards if the protection levels previously identified in this subsection are exceeded. On a case-by-case review, the CED Department shall determine the balance between tree protection that exceeds the established minimum percentage and variations to site development requirements. If adjustments or reductions to site development standards are granted under this provision, then tree protection requirements shall be recorded on the face of the plat, as a notice to title, or on some other legal document that runs with the property. Adjustments that may be considered in exchange for retaining additional trees above the minimum requirements, at the discretion of the city, are:
- Reduction of a rear yard and/or side yard building setback to compensate for significant or heritage tree preservation provided that the setback is not reduced more than five (5) feet, and is the minimum reduction required for tree preservation, and complies with other applicable codes; or
- Increase in the amount of allowable impervious surface by 5%; or
- Reductions or variations of the area, width, or composition of required open space and/or landscaping; or
- Variations in parking lot design and/or any access driveway requirements; or
- Variations of grading and stormwater requirements; or
- Variations in frontage improvements; or
- Reduction in stormwater capital facilities fees.
Tree retention priorities. Developers must demonstrate the following retention priorities in the tree retention plan (not in order of importance): trees in groves, heritage trees, and trees adjacent to parks or other open space areas.
Additional trees must be retained as required by other municipal codes, including regulations for Critical Areas (Chapter 16.15 MTMC), Shoreline Management (Chapter 16.10 MTMC), and Heritage Trees (MTMC 19.130.145).
Tree replacement (MTMC 19.130.190) or tree fee-in-lieu (MTMC 19.130.195) may be utilized if the minimum retention requirements cannot be met.
Any tree removal, site clearing, or site alteration undertaken that does not meet these provisions will be subject to site rehabilitation, as determined by the city, and may be subject to penalties as provided in MTMC 19.130.199 and other applicable codes.
The following protection guidelines shall be imposed for all trees to be retained on site during the construction process:
All required tree protection measures shall be shown on the tree protection and replacement plan, clearing and grading plan, or other plan submitted to meet the requirements of this subchapter. Tree protection shall remain in place for the duration of the permit unless earlier removal is addressed through construction sequencing on approved plans.
Prohibited activities within retained tree drip lines:
- No filling, excavating, stacking, storing of any equipment, or compacting of the earth in any way shall be permitted within the area defined by the drip line of any tree to be retained, except for filling or excavating as recommended by an arborist and approved by the city.
- No impervious surface material may be installed within the area defined by the drip line of any tree to be retained, except as recommended by an arborist and approved by the city; and
- The grade level shall not be lowered or raised within the tree protection zone (TPZ) without a report provided by a qualified arborist and CED Department approval. Approved excavation within the TPZ must use low-impact excavation methods, such as directional boring, pneumatic (air) or hydro excavation, or hand digging to minimize tree disturbance. Any roots two (2) inches diameter or greater that cannot be retained must be cleanly cut at the point of excavation closest to the tree to prevent damage to the root beyond excavation. Rock walls shall be constructed around the tree, equal to the dripline, when existing grade levels are lowered or raised by the proposed grading.
Prior to any land disturbance, temporary construction fences must be placed around the tree protection area. Protective barricades shall be provided around the tree(s) to be protected, placed at the edge of the drip line. If a cluster of trees is proposed for retention, the barrier shall be placed around the edge formed by the drip lines of the trees to be retained. Tree protection shall remain in place for the duration of the permit unless earlier removal is addressed through construction sequencing on approved plans.
Tree protection barriers shall be a minimum of six feet high, constructed of chain link or similar material. “Tree Protection Area” signs shall be posted visibly on all sides of the fenced areas.
Retain small trees, bushes, and understory plants within the tree protection zone, unless the plant is identified as a regulated noxious weed, a nonregulated noxious weed, or a weed of concern by the Snohomish County Noxious Weed Control Board.
Preventative Mitigation. In addition to the above minimum tree protection measures, the applicant shall support tree protection efforts by employing, as appropriate, the following preventative measures, consistent with best management practices for maintaining the health of the tree:
- Pruning of visible deadwood on trees to be protected or relocated;
- Mulching with a layer of four inches to five inches of wood chips within the drip line of retained trees; and
- Ensuring watering adequate to maintain tree health during and immediately after construction from May 1 through September 30, or until reliable rainfall occurs in the fall.
If, at the discretion of the city, tree protection practices employed during site development are insufficient to protect retained trees, the applicant may be required to implement other specific tree protection techniques.
Tree replacement on-site is required for tree removal associated with development, above and beyond required landscaping. Each viable significant tree to be removed shall be replaced as follows:
- For each significant tree between 6 inches and 12 inches DBH removed, 3 replacement trees are required.
- For each significant tree between 12 inches and 24 inches DBH removed, 5 replacement trees are required.
- For each significant tree between 24 inches and 48 inches DBH removed, 7 replacement trees are required.
- For each significant tree greater than 48 inches DBH removed, 10 replacement trees are required.
Replacement trees shall be of any approved species, mutually agreed upon by the applicant and staff, at least 2 inches in diameter measured 6 inches above grade for deciduous trees, and a minimum of 7 feet in height for evergreen trees.
Fee-in-lieu for replacement trees required as per minimum retention requirements in MTMC 19.130.170.D.1 is allowed.
The amount of the fee shall be multiplied by the number of trees necessary to satisfy the tree replacement requirements of MTMC 19.130.190 and shall be deposited into the city’s tree fund.
- The fee shall be paid to the city prior to the issuance of a civil or building permit.
- Exemption: If the development meets the requirements for affordable housing as defined by RCW 84.14.010 for a minimum of 20% of the housing units, tree fee-in-lieu fee requirements are waived.
- Tree replacement fees as specified in the civil engineering construction development fee schedule (in 2024 fee schedule, cost is $781 per replacement tree.) Tree replacement fee is based on wholesale cost for a two (2) inch caliper tree with tax; labor for planting and summer watering for first three (3) years; plus replacement cost for anticipated 20% street tree mortality.
Funding sources for the tree fund are from the following sources:
- All revenue received from fee-in-lieu, mitigation fees, civil fines, and penalties received by the city for illegal removal of trees under violations of clearing and grading, critical areas, land use, or other code for the purpose of tree protection.
- Donations and grants for tree purposes; and;
- Other monies as allocated by the City Council.
The tree fund may be used for the following purposes, as reviewed and approved by the city:
- Providing tree vouchers to residents for the purpose of purchasing and planting trees in the city;
- Paying for services provided by a qualified tree professional;
- Paying for services to support the city’s urban forest management and health;
- Acquiring, maintaining, planting, and preserving wooded areas within the city;
- Purchasing and planting of trees by the city, including planting street trees within parks, the right-of-way, and other public property;
- Purchasing supplies and materials for the city’s observance of Arbor Day;
- Education and outreach on the benefits of trees and tree protection; and
- Other purposes relating to trees as determined by the City Council.
Monies from the tree fund shall not be used to purchase trees required for replacement under the conditions in MTMC 19.130.195, nor used to purchase trees required for mitigation. Further, monies cannot be used in any manner that will benefit the grantee.
City staff will be appointed to manage the tree fund and will provide an annual report on the tree fund status to the Tree Board.
It is unlawful to remove or damage trees in violation of these tree regulations or approved plans. Tree removal includes the removal of a tree, directly or indirectly, or irreversible damage to a tree resulting in the death of the tree. Any person who aids or abets in the violation shall be considered to have committed a violation for purposes of fines. This includes the arborist or company pruning or removing the tree.
- Removal of trees before final tree retention plan approval, or the issuance of a clearing and grading permit during the development process; or
- Removal of trees shown to be retained on an approved tree retention plan; or
- Removal of heritage trees.
Fines and tree restoration costs may be assessed against the responsible party. Civil penalty fines are assessed at $1,500 per inch of diameter at breast height (DBH) of the tree unlawfully removed or damaged. If the DBH of an unlawfully removed or damaged tree cannot be established, the diameter of the remaining stump top shall be used. In cases where the stump has been removed, the city will approximate the size of the removed tree(s) based on available evidence. If inadequate evidence as to the size of the tree exists, the city shall assess a minimum ten thousand ($10,000) dollar civil penalty fine for each unlawfully removed tree. Fines must be paid within 30 days. A property lien may result from the non-payment of fines. Any appeal shall be governed by procedures outlined in Chapter 1.15 MTMC.