Division 5. Environment

Chapter 21.50
DEVELOPMENT STANDARDS – TREE PROTECTION

Sections:

21.50.010    Purpose and intent.

21.50.020    Applicability.

21.50.030    Exemptions.

21.50.040    City Tree Fund established.

21.50.050    Tree permit.

21.50.060    Minimum tree density.

21.50.070    Tree removal on single-family sites with no construction.

21.50.080    Tree removal for subdivisions or short subdivisions.

21.50.090    Tree removal in critical areas.

21.50.100    Supplemental tree planting requirements.

21.50.110    Alternative compliance.

21.50.120    Tree protection during construction.

21.50.130    Tree maintenance requirements.

21.50.140    Additional enforcement.

21.50.010 Purpose and intent.

(1) Introduction. Trees are integral to Woodinville’s community character and protect public health, safety, and general welfare. Protecting, enhancing, and maintaining healthy trees, groves of trees and vegetation are key community values. The City’s goal is to achieve an overall tree canopy coverage of 40 percent. Healthy trees and vegetation contribute to Woodinville’s quality of life through reducing soil erosion and land instability; improving air quality; providing protection from severe weather conditions; providing habitat and food supply for fish and wildlife; enhancing property values and contributing to Woodinville’s natural beauty, aesthetic character, and livability.

(2) Purpose. The purpose of this chapter is to establish processes and standards to provide for the retention, protection, preservation, replacement, proper maintenance, and use of significant trees and woodlands located in the City of Woodinville. The intent of this chapter is to:

(a) Maintain and enhance canopy coverage provided by native trees for their benefits;

(b) Preserve and enhance the City of Woodinville’s environmental, economic, and community character with mature landscapes;

(c) Promote site development practices that work to avoid removal, destruction, or disturbance to significant trees, groves of trees, and the City’s natural vegetation;

(d) Mitigate the consequences of required tree removal in land development through on- and off-site native or naturalized tree replacement to achieve an overall healthy tree canopy cover of 40 percent citywide over time;

(e) Encourage tree retention efforts by allowing flexibility with respect to certain other development requirements;

(f) Implement the goals and objectives of the City’s Comprehensive Plan;

(g) Implement the goals and objectives of the State Environmental Policy Act (SEPA). (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.020 Applicability.

(1) General. Tree removal, trimming, or vegetation clearing within the City limits shall be conducted in accordance to this chapter regardless of whether a permit is required.

(2) Permit Required. Removal of trees not exempted in WMC 21.50.030 shall require a tree permit. Tree permits shall be processed as a Type I project permit pursuant to Chapter 21.83 WMC.

(3) Trimming and Maintenance. Tree trimming, pruning, or maintenance conducted in conformance with WMC 21.50.130 shall not require a tree permit.

(4) Removal of heritage or specimen trees shall not be permitted except under the City’s Heritage Tree Program. (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.030 Exemptions.

(1) Exemptions. The following activities are exempt from the provisions of this chapter:

(a) Any tree that poses a high or extreme risk according to ISA tree risk assessment to life or property, due to a storm event such as a wind storm or ice storm, may be removed without first obtaining a permit. The party removing the tree shall document the high or extreme risk assessment and contact the City Tree Official within seven days of removal to provide documentation of threat for approval of exemption.

(b) Trees may be removed by the City or utility provider in situations involving immediate danger to life or property, interruption of services provided by a utility, or if the necessary utility clearance pruning will remove greater than 50 percent of the tree canopy.

(c) A nursery or tree farm owner may remove trees that are grown for commercial Christmas or landscape tree sales.

(d) Removal of trees with a diameter-at-breast-height of less than two inches.

(e) Removal of nonsignificant trees (diameter-at-breast-height of less than six inches) with a combined maximum of diameter-at-breast height of less 40 inches within a 12-month period.

(f) Trees within the public right-of-way, and trees removed as part of a City construction project, shall be subject to the requirements of Chapter 2.24 WMC.

(g) Remodels or maintenance activities that do not remove trees and do not alter or expand to the footprint of a structure, provided tree protection measures are in place consistent with this chapter.

(h) Tree removal in multifamily, commercial, industrial, and public/institutional zones (R-12 through R-48, CBD, NB, GB, I, or TB zones), except for heritage and specimen trees, shall be subject to Chapter 21.43 WMC.

(i) Tree trimming, pruning, or maintenance conducted in conformance with WMC 21.50.130. (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.040 City Tree Fund established.

(1) Fund Established. A City Tree Fund is established for the collection of any funds used for the purpose and intent set forth by this chapter.

(2) Funding Sources. The following funding sources may be allocated to the City Tree Fund: payments received in lieu of supplemental plantings; civil penalties collected pursuant to this chapter; agreed-upon restoration payments or settlements in lieu of penalties; sale of trees or wood from City property; donations and grants for tree purposes; sale of seedlings by the City; and other monies allocated by City Council.

(3) Funding Purposes. The Public Spaces Commission shall provide recommendations with each budget to the City Council for approval of how the fund will be allocated. The City shall use money received pursuant to this section for the following purposes:

(a) Acquiring, maintaining, and preserving wooded areas within the City;

(b) Planting and maintaining trees within the City;

(c) Identification and maintenance of heritage trees;

(d) Establishment of a holding public tree nursery;

(e) Urban forestry education;

(f) Urban forest canopy coverage assessment; or

(g) Other purposes relating to tree and woodland protection and enhancement as determined by the City Council. (Ord. 675 § 16, 2018; Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.050 Tree permit.

(1) When Required. Unless otherwise exempted in WMC 21.50.030, a development project requiring a construction permit or any proposal to remove trees subject to this chapter shall obtain a tree permit.

(2) Submittal Materials. The following materials are required to obtain a tree permit. The City Tree Official shall have the authority to waive certain application materials if the item is not necessary to evaluate a specific proposal for consistency with this chapter.

(a) Tree permit application, completed and signed by the property owner.

(b) Site plan prepared by an engineer, surveyor, arborist, or other qualified professional, showing the following:

(i) Location of all existing and proposed structures, construction limits, easements, utility lines, and construction protection barriers consistent with WMC 21.43.120;

(ii) Location of all trees above three inches at diameter-at-breast-height (DBH) within 50 feet of the construction limits, including size and species;

(iii) Identification of all trees to be removed and/or relocated;

(iv) Location of temporary tree protection fencing, signage, material storage, silt fencing, and other construction details as necessary;

(v) Existing and proposed topography at five-foot intervals; and

(vi) Location of all critical areas and buffers.

(c) Replanting plan, showing the following:

(i) Location of proposed structures and retained trees;

(ii) Location of proposed replacement trees and/or vegetation, including species, size, and spacing;

(iii) Location and design of other landscape restoration measures;

(iv) A planting schedule that indicates species, quantity, size, spacing, and tree density calculations for replanted trees; and

(v) Irrigation system, including location and specifications; and

(d) Arborist report or professional recommendation, evaluating the following:

(i) Inventory of all impacted trees, including size, species, dripline, and critical root zone. The inventory must include all trees proposed for removal, any trees within 50 feet of the construction limits on the subject property and any neighbor’s trees with canopy overhanging the construction limits. Written evaluation of anticipated impacts to tree health and viability resulting from construction, including any impacts to critical root zones;

(ii) Information on compliance with coverage requirements, including a calculation of tree canopy or replanting schedule;

(iii) Evaluation of impacts on dripline and critical root zone of trees on adjoining properties;

(iv) Suggested location and species of supplemental trees, maintenance, and planting specifications consistent with WMC 21.50.100;

(v) Recommendations on tree protection measures consistent with WMC 21.43.120 and corresponding to the site plan in subsection (2)(b) of this section;

(vi) Special instructions for working within the protection area, including, but not limited to, hand-digging, tunneling, root pruning, and minimizing grade changes;

(vii) Information on any required on-site supervision during construction;

(viii) Information on maintenance including duration, benchmarks for success, cost estimates, and financial guarantees/bonding; and

(ix) If applicable, assessment and designation of a hazard or nuisance tree. (Ord. 589 § 2, 2016)

21.50.060 Minimum tree density.

(1) Minimum Tree Density Required. Any proposal subject to a tree permit pursuant to WMC 21.50.050(1), except as provided for single-family lots subject to WMC 21.50.070, shall be required to meet minimum tree density of 70 tree credits per acre for residential zone R-1 and 50 tree credits per acre for residential zones R-4 through R-8. Minimum tree density shall be calculated by multiplying the required tree density by the lot area. Nonresidential uses are required to meet the landscape standards pursuant to Chapter 21.43 WMC.

(2) Area Calculation. For the purposes of calculating required minimum tree density, right-of-way, and areas to be dedicated as right-of-way, shall be excluded from the lot area used for calculation of tree density.

(3) Tree Density Credit Calculation. The minimum tree density credits are calculated through a tree credit calculation using Table 21.50.060(3). The tree credit calculation is the sum of all retained existing trees and any supplemental tree plantings. If a site falls below the minimum tree density with existing trees, supplemental planting shall be required pursuant to WMC 21.50.090. The tree credit value shall correspond with diameter-at-breast-height in Table 21.50.060(3):

Table 21.50.060(3) – Tree Credit Calculation

Tree Diameter Inches

Total Credit

Minimum

Maximum

2.0

2.9

0.50

3.0

5.9

0.75

6.0

8.9

1.5

9.0

14.9

2.0

15.0

17.9

3.0

18.0

23.9

4.0

24.0

35.9

6.0

36.0 and above

8.0

(a) Tree diameter inches shall be determined in diameter-at-breast-height, which is the diameter of the tree as measured four and one-half feet off the ground for existing trees and six inches off the ground for new plantings. The measured tree diameter shall be its size at the time of permit submittal.

(b) For multi-trunk trees splitting at the ground level, the tree diameter inches shall be determined by taking the square root of the sum of all squared stem caliper.

(c) Existing trees transplanted to an area on the same site may count toward the required density if approved by the City Tree Official based on transplant specifications provided by a qualified tree professional that will ensure a good probability for survival.

(d) Trees shall be planted in accordance with WMC 21.50.100. On sites where additional plantings are not feasible due to spacing or other site constraints, an applicant may satisfy the minimum tree density requirement through payment into the City Tree Fund pursuant to WMC 21.50.100(4)(f). (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.070 Tree removal on single-family sites with no construction.

(1) Sites with No Construction. This section shall apply only to lots located within single-family residential zones (R-1 through R-8) where no exterior construction or demolition, grading, material storage, or other development activity is proposed, and no development permit application is pending or approved for the subject property.

(2) Performance Requirements. Tree removal on single-family residential zone sites with no construction shall meet the following:

(a) On any single legal parcel, up to two trees may be removed per 12-month period or four trees per 24-month period. Tree removal shall comply with minimum tree density requirements of this chapter or complete replacement plantings; provided, that no replacement planting or minimum tree density compliance is required for the first two tree removal permits issued under this subsection, regardless of any change in ownership, after December 1, 2016, provided the following is met:

(i) Tree removal does not include heritage or specimen trees; and

(ii) Tree removal is located outside of all critical areas and its buffer, NGPA or shared ownership tracts subject to WMC 21.50.090.

(b) Removal of more than two trees per 12-month period or four trees per 24-month period shall only be permitted under the discretion of the Development Services Director for the purposes of tree thinning or removal of dead, nuisance, hazard trees. Tree thinning is the selective removal of trees to improve health of remaining trees, and shall apply to existing trees planted less than seven feet on-center or at the recommendation of an arborist. Tree removal shall require compliance with the minimum tree density or replacement at a rate of three trees per each removed tree.

(3) Future Development. Any development triggering a construction permit on a single-family lot shall be required to comply with this chapter. If tree removal under this section results in a site that falls below the minimum tree density, supplemental plantings meeting the requirements of WMC 21.50.100 shall be required. (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.080 Tree removal for subdivisions or short subdivisions.

(1) Subdivisions and Short Subdivisions. This section applies to tree removal associated with applications for subdivision or short subdivision.

(2) Performance Requirements. Tree removal on lots undergoing subdivision or short subdivision shall meet all of the following:

(a) The overall site must achieve the minimum tree density pursuant to WMC 21.50.060.

(b) The site shall retain at least 10 percent of the tree density credits of all existing healthy, viable significant trees within the property boundaries prior to subdivision or construction work.

(i) This requirement may be reduced for preservation of groves with five or more trees consistent with WMC 21.50.110.

(ii) In certain circumstances where tree removal results in less than 10 percent of tree density credits retained due to site conditions, infrastructure conflicts, or other conditions beyond the applicant’s control, the City Tree Official may grant an exception. The applicant shall pay for the remaining tree density credits at double the rate specified in WMC 21.50.100(4)(f) in addition to any other payment required by this chapter.

(c) Prior to issuance of a certificate of occupancy or plat recording, the proponent shall provide a final as-built tree plan and an agreement to maintain and replace all trees that are required by the City.

(d) The applicant shall submit a preservation and maintenance agreement for trees located in common areas, including streets, drainage features, parks, or other jointly maintained spaces. The document shall be approved and recorded prior to occupancy, recording, or final inspection.

(e) When forest or critical areas are preserved in a Native Growth Protection Area (NGPA) tract pursuant to WMC 21.51.150, any remaining tree credits within the NGPA above the required minimum tree density may be applied towards the entire subdivision. The remaining tree credits will be equally divided among the total number of lots. Where the tree credits in the NGPA have not been determined, the minimum tree density shall apply to each lot within the subdivision.

(f) A final arborist report shall be submitted at the end of the project verifying the total trees removed, retained, and planted, prior to release of the performance bond.

(g) Street trees shall be planted at an average of 25 feet on center consistent with WMC 2.24.100.

(h) Subdivisions that abut arterial streets shall provide additional tree plantings at a rate of one tree per 25 feet in the street setback for the arterial. (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.090 Tree removal in critical areas.

(1) Tree Removal in Critical Areas. Within critical areas or critical area buffers, only hazard, nuisance, or dead trees may be removed or trimmed. If more than two trees are removed, the City Tree Official may require submittal of a critical areas alteration pursuant to Chapter 21.50 WMC.

(a) Tree removal proposed within a NGPA or an area under common ownership shall meet tree density requirements pursuant to WMC 21.50.060. The applicant shall obtain signatures from a majority of owners who hold interest in the land or if applicable, approval from the homeowner’s association.

(b) The priority action for a tree proposed for removal is to create a “snag” or wildlife tree. If creating a snag or wildlife tree is not feasible, the felled tree shall be left in place.

(c) Supplemental trees shall be planted consistent with WMC 21.50.060 and 21.50.100. The requirements may be modified if a qualified tree professional determines to the satisfaction of the City Tree Official that equal or better habitat function and values can be achieved through the following:

(i) Native understory plantings are installed;

(ii) Invasive species removal is conducted;

(iii) A coverage analysis is submitted stating that the replanted trees will have equal or better coverage than the trees removed within 15 years; and

(iv) A replanting plan is submitted. (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.100 Supplemental tree planting requirements.

(1) Supplemental Trees. Sites and activities requiring supplemental trees shall be planted to achieve the required minimum tree density. Tree density credits for supplemental trees shall be calculated pursuant to WMC 21.50.060.

(2) Tree Species. The tree species chosen for the supplemental plantings shall either be trees of the same mix of species as the removed trees or mix of species listed in the Woodinville Plant Species List. Trees should be selected and sited to produce a hardy and drought-resistant landscape area.

(3) Tree Size and Spacing. The required minimum size for any supplemental tree is two-inch caliper or greater for deciduous species and six feet or taller for coniferous species. Trees shall be spaced appropriately based on the Woodinville Plant Species List.

(4) Tree Location. In designing a development and in meeting the required minimum tree density, the trees shall be planted in the following order of priority:

(a) Adjacent to preserved groves, critical areas or its buffers;

(b) Adjacent to stormwater facilities, within entrance landscaping, traffic islands, and other common areas in residential subdivisions that have enough area to support mature trees of the planted species;

(c) Site perimeter and/or required landscaped setbacks;

(d) Individual building lots;

(e) Off site, when room is not available on site to ensure long-term health and viability for the trees. Trees shall be planted at another location within 2,500 feet of the subject site where the trees were removed and as approved by the City Tree Official; and

(f) If trees cannot be planted in accordance with subsections (4)(a) through (e) of this section, the applicant may satisfy the requirements by paying into the City Tree Fund $500.00 per tree credit.

(5) Installation. All required trees shall be installed according to sound horticultural practices in a manner designed to encourage quick establishment and healthy plant growth.

(a) Timing. All trees shall be installed prior to the issuance of a certificate of occupancy or plat recording. The time limit for compliance may be extended to allow installation during the next planting season or deferred due to diseased soil or pest infestation. A determination shall be made at the discretion of the City Tree Official. Deferred installation shall be secured with a performance bond pursuant to Chapter 15.42 or 21.60 WMC.

(b) Placement. All supplemental trees shall be located at least seven feet from the property lines, and shall be installed in the ground and not in aboveground containers.

(c) Grading. Berms shall not exceed a slope of two horizontal feet to one vertical foot (2:1).

(d) Soil Specification. Soils in planting areas shall have adequate porosity to allow root growth and adequate drainage. Compacted soils shall be loosened to a minimum depth of 24 inches or to the depth of the largest plant root ball, whichever is greater. Imported topsoils shall be tilled into existing soils to prevent a distinct soil interface from forming.

(e) Soil Fertility. The organic content of soils in any planting area shall be as necessary to provide adequate nutrient and moisture-retention levels for the establishment of plantings. Additional fertilization shall be the minimum necessary.

(f) Irrigation. Irrigation system shall be designed to ensure plant establishment. Irrigation shall be designed to conserve water by using best management techniques available, including, but not limited to: drip irrigation; moisture sensors; automatic controllers; spacing designed to minimize overspray; and separate zones for different planting areas.

(i) Within rights-of-way and common areas, permanent irrigation with an automatic controller shall be installed for tree plantings. Temporary irrigation, providing sufficient water to ensure plant survival and establishment, may be approved at the discretion of the City Tree Official.

(ii) For individual residential lots, the applicant may choose permanent irrigation, temporary irrigation, or irrigation by hand.

(iii) Modifications to the irrigation requirement may be approved by the City Tree Official for less water-intensive strategies such as planting native vegetation that does not require supplemental irrigation, low impact development, established native plant material, or where natural appearance is acceptable or desirable to the City.

(g) Mulch. Required plantings shall be covered with two inches or more of organic mulch to minimize evaporation and runoff. Mulch shall consist of materials such as yard waste, sawdust, bark or wood chips, and/or organic compost. All mulches shall be kept at least six inches away from the trunks of shrubs and trees.

(h) Protection. All required trees must be protected from potential damage by adjacent uses and development, including parking and storage areas. Protective devices such as bollards, wheel stops, trunk guards, and root protection barriers shall be required in the right-of-way or in common areas as needed to protect required trees. (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.110 Alternative compliance.

(1) Additional Density Credits. The applicant may earn additional tree density credits through alternate measures or procedures that will be equal to or better than the provisions in this chapter. If the City Tree Official determines that the proposal meets the purpose and intent of the code through alternative compliance, the Official may grant tree density credits for alternative measures.

(2) Criteria. The City Tree Official shall review each alternative compliance request based on the following criteria:

(a) The alternative is designed to ensure the long-term health and maturity of the tree;

(b) The alternative will provide increased environmental benefits including natural function and value beyond the standard requirements;

(c) If applicable, the alternative will enhance or improve critical areas or NGPA areas;

(d) The alternative will not increase soil erosion, slope instability, nor create drainage issues; and

(e) The alternative provides equivalent or greater compliance with the tree code.

(3) Qualifying Activities. The following activities or strategies may qualify for alternative compliance:

(a) Retention of specimen or heritage trees and groves of at least five trees may earn up to an additional 10 percent of the tree credits of the subject tree or grove.

(b) Green roofs may earn up to one tree credit for every 200 square feet up to a maximum of 10 tree credits.

(c) Planting 200 square feet of understory landscaping within the canopy area of each supplemental tree may earn up to 15 percent of the tree credits for the subject tree. Understory landscaping must include shrubs that will mature to a full range of understory plant heights, 18 inches to 15 feet tall or greater. (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.120 Tree protection during construction.

(1) Tree protection measures shall be installed prior to development activity or initiating tree removal on the site. These standards must be adhered to and included on grading and building plans as necessary. A pre-construction meeting on site between the City Tree Official and the contractor shall be held prior to site disturbance.

(2) Tree protection measures shall include, but are not limited to, the following:

(a) Protective Barrier. A visible temporary protective fencing extending to the edge of the critical root zone of all retained trees shall be installed prior to site disturbance and maintained until removal is authorized by the City Tree Official. Fences shall be constructed of chain link and be at least four feet high, unless other type of fencing is authorized by the City Tree Official. Visible signs shall be spaced no further than 25 feet along the entirety of the protective tree fence. Said signs must be approved by the City Tree Official and shall state at a minimum “Tree Protection Area, Entrance Prohibited” and provide the City phone number for code enforcement to report violations.

(b) Construction Activities. No excavation, storage, parking, construction vehicle access, dumping of toxic or polluted materials, or other potentially damaging activity is allowed within the protective barrier. If construction activity within the protective barrier is unavoidable, the City Tree Official may allow such activities approved by and the following activities under the supervision of a qualified tree professional retained by the applicant:

(i) Equipment may be authorized to operate within the critical root zone, if no other alternative is feasible. The areas adjoining the critical root zone of a tree shall be covered with mulch to a depth of at least six inches, or with plywood, metal or similar material in order to protect roots from damage caused by heavy equipment.

(ii) Utility trenches should be located outside of the critical root zone of trees. If utilities must be placed within the critical root zone, a qualified tree professional shall review the proposal to ensure the long-term viability of the trees. The work shall minimize root damage by excavating a two-foot-deep trench, at edge of critical root zone, to cleanly sever the tree roots.

(iii) Corrective pruning may be performed on protected trees in order to avoid damage from machinery or building activity.

(iv) Site grading within the critical root zone shall be the minimum necessary. The applicant’s qualified tree professional shall establish the maximum amount of earthwork allowable in the critical root zone that will not imperil the survival of the tree. Suitability of activities shall be based on construction techniques, erosion potential, damage to the critical root zone, stabilization techniques, and other similar factors.

(c) Exposed Soils. Trees and other vegetation to be retained shall be protected from erosion and sedimentation. Clearing activities shall be conducted so as to expose the smallest practical area of soil to erosion for the least possible time. To control erosion, it is encouraged that shrubs, ground covers, and stumps be maintained on the individual lots, where feasible.

(d) Directional Felling. Directional felling of trees shall be used to avoid damage to trees designated for retention. Any trees designated for preservation, per the approved tree plan, that are significantly damaged or destroyed during felling of trees approved for removal shall be replaced per WMC 21.50.060.

(e) Additional Requirements. The City Tree Official may require additional tree protection measures that are consistent with accepted urban forestry practices. (Ord. 611 § 8 (Att. A), 2016; Ord. 589 § 2, 2016)

21.50.130 Tree maintenance requirements.

(1) The following maintenance requirements apply to all trees planted or preserved consistent with this chapter:

(a) Responsibility for Regular Maintenance. The applicant, landowner, or successors in interest shall be responsible for the regular maintenance of the trees. Maintenance of all landscaping installed as part of a development project within the right-of-way shall be the responsibility of the abutting property owner unless alternative conditions are approved by the City.

(b) Replacement. Trees that are dead and removed shall be replaced in-kind by the property owner, unless the site meets the tree density credit. Plantings shall be replaced within three months or during the next planting season if the loss does not occur in a planting season.

(c) Maintenance Duration. Trees shall be maintained for the life of the development. A maintenance guarantee pursuant to Chapter 15.42 or 21.60 WMC shall be secured for a period of three years following the issuance of the certificate of occupancy or plat recording.

(d) Maintenance of Preserved Grove. Any applicant who has a grove of trees identified for preservation on a site plan shall provide prior to occupancy or plat recording the legal instrument acceptable to the City to ensure preservation of the grove and associated vegetation. The agreement may be extinguished if the City Tree Official determines that preservation is no longer appropriate.

(e) Non-Native Invasive and Noxious Plants. It is the responsibility of the property owner to remove non-native invasive plants and noxious plants. Removal must be performed in a manner that will not harm the tree or other vegetation that the City has required to be planted or protected.

(f) Pesticides, Herbicides, and Fertilizer. The use of pesticides, herbicides, or fertilizer shall be by special approval of the City Tree Official only.

(2) Planting Plans and Utility Plans. Planting plans and utility plans shall be coordinated. In general, the placement of trees should be adjusted based on the tree’s mature size and to the location of utility routes both above and below ground.

(3) Tree Pruning. Topping or pruning to the extent that would constitute tree removal as defined in Chapter 21.11 WMC is prohibited. If a supplemental tree smaller than six inches in diameter-at-breast-height is topped, it must be replaced pursuant to the standards in WMC 21.50.100. If a supplemental tree six inches or larger in diameter-at-breast-height is topped, the property owner may be subject to enforcement actions pursuant to WMC 21.50.140. Trees may be windowed or limbed up using best management practices. This method of tree pruning shall maintain the health of the tree.

(4) Pruning Techniques. The following techniques for healthy pruning shall be used. No permit is required for pruning; however, all pruning should be done under the direction of a qualified tree professional and adhere to the ANSI A300 pruning standards.

Table 21.50.130(4) – Pruning Techniques

Healthy Pruning Techniques

Improper Pruning Techniques

Crown Cleaning – removing dead, dying, diseased, crowded, weakly attached, or low-vigor branches in a manner that should not reduce the canopy.

Topping – the cutting of a trunk or main branch to the point where there is no branch large enough and vigorous enough to become the new leader.

Crown Thinning – selective removal of branches throughout the crown of the tree to improve interior light and air. Remaining branches should be well-distributed and balanced.

Stripping – removing the branches from the inner section of the trunk or branch. Can cause structural imbalances and potential failure.

Crown Raising – removal of the lower branches of the tree to provide height clearance, typically 8 feet for pedestrians and 16 feet for vehicles.

Imbalance – removing portions of the tree and creating an imbalance in the structure of the tree. Can cause cracking damage from the wind through twisting or weak new growth.

Windowing – removing several branches symmetrically within an area of the tree’s crown to enhance views.

Excessive Pruning – removing portions of the tree to a point where it can kill the tree. Can invite decay and disease.

(Ord. 589 § 2, 2016)

21.50.140 Additional enforcement.

In addition to the enforcement provisions set forth in Chapters 1.06 and 21.12 WMC, the following shall apply to enforcement of the tree code:

(1) Tree Restoration. A restoration plan and arborist report shall be submitted that results in a site condition that, to the greatest extent practical, equals the site condition that would have existed in the absence of the violation(s). The restoration plan shall be prepared in accordance with WMC 21.50.070 and include supplemental trees equal to the number of tree credits illegally removed.

(a) In the event the violators cannot restore the unlawfully removed or damaged trees due to site conditions as determined by the Director, the violators shall make payment to the City Tree Fund. Unless otherwise determined to base the restoration costs on appraised value, the amount paid will be the City’s unit cost for a restoration tree as calculated in WMC 21.50.100(4)(f).

(b) Violators of this chapter or of a permit issued thereunder shall be responsible for restoring unlawfully damaged areas in conformance with this chapter.

(c) In cases where the violator intentionally or knowingly violated this chapter or committed previous violations of this chapter, restoration costs shall be paid at the discretion of the Director. Restoration costs may be based on the City-appraised tree value of the subject trees in which the violation occurred, utilizing the industry standard trunk formula method in the current edition of “Guide for Plant Appraisal.” If diameter of removed tree is unknown, determination of the diameter size shall be made by the Director by comparing size of stump and species to similar trees in similar growing conditions. The amount of costs above the approved restoration plan will be paid into the City Tree Fund.

(2) Failure to Restore or Pay Fines. The City shall not approve any application for a subdivision, short subdivision, or any other development permit or approval or issue a certificate of occupancy for property on which a violation of this chapter has occurred until the violation is cured by restoration or other means accepted by the Director and by payment of any penalty imposed for the violation. (Ord. 685 § 22, 2019; Ord. 589 § 2, 2016)