9.6885 Tree Preservation and Removal Standards

9.6885 Tree Preservation and Removal Standards.

This section has been amended by Ordinance No. 20705, which is pending codification.

(1) Exemptions from Standards. The standards in this section do not apply to activities regulated under EC 9.4900 through 9.4980, or an application for development activity that includes or will result in:

(a) Residential Lots Under 20,000 Square Feet. Removal of significant trees from a parcel of property not subject to the provisions of subsection (c) of this section with an area of less than 20,000 square feet when:

1. Such parcel is occupied by a single-unit dwelling, accessory dwelling, or middle housing;

2. An application to construct a single-unit dwelling, accessory dwelling, or middle housing on such lot is being reviewed by the city. However, no significant trees may be removed prior to the approval of the development permit; or

3. The city has entered into an agreement authorizing the start of construction for a single-unit dwelling, accessory dwelling, or middle housing.

(b) Lots 20,000 Square Feet or Larger. Removal of up to 5 significant trees within a period of 12 consecutive months from a parcel of property not subject to the provisions of subsection (c) of this section consisting of 20,000 or more square feet of area;

(c) Land Use Approvals. Any tree removal on property subject to an approved Conditional Use Permit, Planned Unit Development, Site Review, Subdivision, or Willamette River Greenway Permit that includes a tree removal/preservation plan or conditions related to tree removal or retention. In those areas, that plan or city approved modifications thereto control tree removal. This exemption does not apply to the removal of a street tree, which must be authorized by a permit issued pursuant to EC 6.305;

(d) Tree Removal Permit. Any tree removal specifically authorized by, and carried out in conformity with a city-approved tree removal permit under EC Chapter 6.

(e) Habitat Restoration. Removal of trees by the city or as authorized by the city for the purpose of implementation of a city-approved habitat restoration plan, and the express purpose of the plan is to restore native plant communities, enhance fish or wildlife habitat, or similar restoration purposes;

1. The removal of hazardous trees on private property, provided that prior to removal the property owner submits to the city a written evaluation of each tree proposed for removal prepared by a certified arborist declaring the tree(s) to be hazardous and recommending immediate removal. The written evaluation shall be on a form prescribed by the city manager pursuant to section 2.019 City Manager – Administrative and Rulemaking Authority and Procedures;

2. The removal of hazardous trees by the city or under contract with the city, on public property or street right-of-way, provided the city’s urban forester issues a written evaluation of each tree proposed for removal declaring the tree(s) to be hazardous and recommending immediate removal;

(g) Fire Hazard Abatement. Removal of trees that the city fire marshal has declared in writing poses a potential fire hazard to existing structures; or

(h) Diseased or Dying Trees. Removal of a diseased or dying tree, provided that prior to its removal the property owner submits to the city a written evaluation of the tree prepared by a certified arborist certifying the unhealthy condition of the tree and recommending its immediate removal. The written evaluation shall be on a form prescribed by the city manager pursuant to section 2.019 City Manager – Administrative and Rulemaking Authority and Procedures.

(2) Tree Preservation and Removal Standards. The standards in this subsection apply only to land use applications processed under EC 9.8100, EC 9.8325, EC 9.8445, EC 9.8520, and EC 9.8812. Unless exempt under subparagraph (d) below, no permit for a development activity subject to this section shall be approved until the applicant demonstrates compliance with the standards in this subsection.

(a) Definitions. For the purposes of this subsection (2), the following definitions apply:

1. Critical Root Zone (CRZ). That area surrounding a tree that has a radius of 12 inches multiplied by the diameter breast height expressed in inches of the tree trunk or trunks.

2. Tree Removal. To fell or sever a tree or to use any procedure the natural result of which is to cause the death or substantial destruction of the tree. Substantial destruction includes actions that destroy more than 20% of the critical root zone of a tree, or topping, or severing the cambial material on 50% or more of the circumference of the tree trunk. Remove does not in any context include those pruning standards as defined in the 2014 edition of American National Standards Institute (ANSI) Section A300, Tree, Shrub and Other Woody Plant Maintenance Standard Practices.

(b) For the purposes of this subsection (2), the South Hills Area is defined as all property located within the City’s adopted Urban Growth Boundary, above an elevation of 500 feet, and:

1. South of 18th Avenue,

2. South of Franklin Boulevard and East of the intersection of 18th Avenue and Agate Street, or

3. If 18th Avenue were extended from the intersection of 18th Avenue and Willow Creek Road directly west to the Urban Growth Boundary, the area south of that extension of 18th Avenue.

(c) For the purposes of this subsection (2), the Willamette River Greenway is defined as all lands within the adopted Willamette River Greenway Boundary established by Resolution No. 2592, and the Willamette River Greenway Setback is that area identified on the Willamette River Greenway Setback Map adopted as Exhibit A-1 to Ordinance No. 20693 .

(d) Exemptions. A proposed development shall be exempt from the requirements of EC 9.6885(2) if any of the following apply:

1. Except as provided in subparagraphs 4. and 5., the area of the development site is less than 20,000 square feet.

2. Except as provided in subparagraph 5., five or fewer significant trees exist on the development site prior to development.

3. Except as provided in subparagraph 5., the development site is zoned R-2 Medium-Density Residential, R-3 Limited High-Density Residential, R-4 High Density Residential, GO General Office, C-2 Community Commercial, or C-3 Major Commercial zones.

4. Notwithstanding subparagraph 1., development sites that include property at or above 900 feet elevation are subject to the requirements of EC 9.6885(2), regardless of the area of the development site.

5. Notwithstanding subparagraphs (1) through (4) above, any portion of a development site located within Willamette River Greenway Tree Preservation Zones 1-3, shall be subject to the requirements of EC 9.6885(2). Willamette River Greenway Tree Preservation Zones are identified on the map adopted as Exhibit B-1 to Ordinance No. 20693 .

(e) Tree Preservation Requirements. Unless adjusted per EC 9.8030(13), significant trees must be preserved in accordance with the requirements of Table 9.6885(2)(e). Minimum preservation is based on the total existing Diameter Breast Height (d.b.h.) of significant trees within each specific location category prior to development. Maximum mitigation is the percentage of the minimum preservation that may be mitigated according to subsection 2. below.

Table 9.6885(2)(e) Tree Preservation and Mitigation
Location Category	Minimum Preservation	Maximum Mitigation
Outside the South Hills Area	40%	100%
Within the South Hills Area, between 500 feet and 900 feet elevation	50%	50%
Within the South Hills Area, at or above 900 feet elevation	50%	0%
Willamette River Greenway Tree Preservation Zone 1 (See Exhibit B-1 to Ordinance No. 20693 )	50%	0%
Willamette River Greenway Tree Preservation Zone 2 (See Exhibit B-1 to Ordinance No. 20693 )	50%	50%
Willamette River Greenway Tree Preservation Zone 3 (See Exhibit B-1 to Ordinance No. 20693 )	40%	100%

1. A Tree Preservation and Removal Plan is required except as provided in EC 9.6885(2)(d) or EC 9.6885(2)(e)3. The plan must be prepared by a certified arborist, licensed landscape architect, licensed engineer, or licensed surveyor and shall provide the following:

a. A table, organized by the location categories listed in Table 9.6885(2)(e), listing all significant trees on the development site and including the following information for each listed tree:

(1) Diameter Breast Height (d.b.h.)

(2) Preservation, removal, or mitigation status

(3) Common name, genus and species

b. A site plan that includes the following information:

(1) The locations of all significant trees on the development site, the Diameter Breast Height (d.b.h.) for each significant tree, whether each significant tree is to be preserved, removed, or mitigated according to EC 9.6885(2)(e)2., and the location of the critical root zone (CRZ) for each significant tree to be preserved.

(2) The location of all existing and/or proposed public and private utility easements, driveways, and areas of grading or excavation on the development site.

(3) The location of all existing development on the site as well as the location of development proposed in the land use application that triggers the requirement for a Tree Preservation and Removal Plan.

(4) Proposed lot or parcel boundaries.

(5) For development sites with any portion located within the South Hills Area, identification of areas at or above 500 feet elevation and areas at or above 900 feet elevation.

c. A written statement from a certified arborist or licensed landscape architect that the Tree Preservation and Removal Plan meets EC 9.6885(2)(e) Tree Preservation Requirements. If the Tree Preservation and Removal Plan is prepared by a certified arborist or licensed landscape architect, then the written statement otherwise required by this subparagraph is not required.

2. Mitigation. An applicant may elect to mitigate a portion of the minimum preservation of significant trees on the development site as provided below:

a. The maximum d.b.h. that can be mitigated shall be based on location category as provided in Table EC 9.6885(2)(e) Tree Preservation and Mitigation.

b. Proposed subdivisions in areas outside of the South Hills Area and outside of the Willamette River Greenway Boundary may mitigate up to 100% of the minimum tree preservation requirement by either:

(1) Providing that lots up to 7,000 square feet in area will contain a minimum of two trees and lots 7,000 square feet or more will contain a minimum of three trees; or

(2) Providing one replacement tree for each significant tree designated for mitigation.

c. Required mitigation may only occur within the Willamette River Greenway Setback if the proposed trees to be planted are selected from the native trees included on the City’s adopted list of plant species for sites at or below 500 feet in elevation, attached as Exhibit F to Ordinance No. 20351 .

d. Installation and Maintenance. Unless otherwise specified, each significant tree designated for mitigation must be replaced with one tree selected from the approved species listed in Table 9.6885(2)(e)2 within one year from the date of removal or prior to final occupancy, whichever is later. Trees planted in accordance with subparagraph (2)(e)2.b. must be planted prior to final occupancy. At the time of planting, deciduous trees used for replacement must have a minimum diameter of 2 inches and evergreen trees used for replacement must be a minimum of 5 feet in height as measured according to the 2014 edition of the American Standard for Nursery Stock (ANSI Z60.1), published by the American Nursery and Landscape Association. Any mitigation trees to be planted within the Willamette River Greenway Setback shall be selected from the native trees included on the City’s adopted list of plant species for sites at or below 500 feet in elevation, attached as Exhibit F to Ordinance No. 20351 .

e. The maximum mitigation allowance may be adjusted in accordance with EC 9.8030(13).

Table 9.6885(2)(e)2. Approved Species List
Genus and Species	Common Name
Abies koreana	Silver Korean Fir
Abies pinsapo	Spanish Fir
Acer circinatum	Vine Maple
Acer ginnala	Amur Maple
Acer glabrum var. douglasii	Rocky Mountain Maple
Acer griseum	Paperbark Maple
Acer macrophyllum	Big Leaf Maple
Acer rubrum	Red Maple
Acer saccharum	Sugar Maple
Alnus rhombifolia	White Alder
Alnus rubra	Red Alder
Amelanchier alnifolia	Pacific Serviceberry
Arbutus menziesii	Pacific Madrone
Arbutus unedo	Strawberry Madrone
Arbutus 'Marina'	Marina Strawberry Tree
Betula nigra	River Birch
Calocedrus decurrens	Incense Cedar
Carpinus betulus	European Hornbeam
Carpinus caroliniana	American Hornbeam
Castanopsis cuspidate	Japanese Chinquapin
Catalpa speciose	Northern Catalpa
Cedrus atlantica	Atlas Cedar
Cedrus deodara	Deodar Cedar
Cedrus libani	Cedar of Lebanon
Celtis occidentalis	Common Hackberry
Cercidiphyllum japonicum	Katsura Tree
Chrysolepis chrysophylla	Golden Chinquapin
Cinnamomum chekiangense	Camphor Tree
Cornus nuttallii	Pacific Dogwood
Corylus colurna	Turkish Filbert
Cupressus arizonica	Arizona Cypress
Cupressus bakeri	Modoc Cypress
Cupressus leylandii	Leyland Cypress
Fraxinus latifolia	Oregon Ash
Fraxinus ornus	Flowering Ash
Ginkgo biloba (fruitless cultivars only)	Ginkgo
Koelreuteria paniculate	Goldenrain Tree
Maackia amurensis	Maackia
Nyssa sylvatica	Tupelo, Black Gum
Ostrya virginiana	American Hophornbeam
Oxydendrum aroboreum	Sourwood
Parrotia persica	Persian Ironwood
Picea smithiana	Morinda Spruce
Pinus ponderosa	Ponderosa Pine
Pinus ponderosa var. benthamania	Willamette Valley Ponderosa Pine
Pinus wallichiana	Himalayan Pine
Pistacia chinensis	Chinese Pistachio
Platanus acerifolia	London Plane
Prunus virginiana	Chokecherry
Pseudotsuga menziesii	Douglas Fir
Quercus acutissima	Sawtooth Oak
Quercus agrifolia	Coast Live Oak
Quercus alba	White Oak
Quercus bicolor	Swamp White Oak
Quercus chrysolepis	Canyon Live Oak
Quercus douglasii	Blue Oak
Quercus frainetto	Hungarian Oak
Quercus gambelii	Gambel Oak
Quercus garryana	Oregon White Oak
Quercus hypoleucoides	Silver Oak
Quercus ilex	Holly Oak
Quercus kelloggii	California Black Oak
Quercus lobate	Valley Oak
Quercus macrocarpa	Bur Oak
Quercus myrsinifolia	Chinese Evergreen Oak
Quercus palustris	Pin Oak
Quercus phellos	Willow Oak
Quercus rubra	Red Oak
Quercus shumardii	Shumardii Oak
Quercus suber	Cork Oak
Quercus wislizeni	Interior Live Oak
Rhamnus purshiana	Cascara Buckthorn
Salix lucida ssp. Lasiandra	Pacific Willow
Salix scouleriana	Scouler’s Willow
Sciadopitys verticillate	Japanese Umbrella Pine
Sequoia sempervirens	Coast Redwood
Sequoiadendron giganteum	Giant Sequoia
Stewartia pseudocamellia	Stewartia
Styrax japonicus (japonica)	Japanese Snowbell
Taxodium distichum	Bald Cypress
Taxus brevifolia	Pacific Yew
Thuja plicata	Western Red Cedar
Tilia Americana	American Linden
Tilia cordata	Little Leaf Linden
Tilia tomentosa	Silver Linden
Tsuga canadensis	Canadian Hemlock
Tsuga heterophylla	Western Hemlock
Tsuga mertensiana	Mountain Hemlock
Tsuga sieboldii	Southern Japanese Hemlock
Ulmus americana	American Elm
Ulmus carpinifolia	Smoothleaf Elm
Ulmus parvifolia	Chinese Elm
Ulmus propinqua	Japanese Elm
Umbellularia californica	California Bay Laurel
Zelkova serrata	Zelkova

a. A Tree Preservation and Removal Plan is not required if the applicant chooses to preserve at least 50 percent of the total existing d.b.h. of significant trees on the development site within one or more tree preservation area(s) and the following requirements are met:

(1) Tree preservation area(s) must be delineated and shown on a site plan submitted for approval by the City.

(2) Applicant must provide written certification from a certified arborist or licensed landscape architect stating that the area(s) designated for tree preservation include(s) at least 50 percent of the total existing d.b.h. of significant trees on the development site.

(3) No trees within the Willamette River Greenway Setback may count toward the 50 percent preservation requirement.

b. Mitigation is not allowed when the Tree Preservation Area Alternative is used to meet tree preservation requirements, except as approved through an adjustment review according to EC 9.8030(13).

4. Protection Standards. The following notes must be included on the final plan set submitted for approval by the City and shall apply at the time of development:

a. “Protective fencing for trees identified to be preserved shall be installed by the applicant and inspected by the City prior to beginning any development activities. All protective tree fencing must remain in place until completion of all construction activities; any relocation, removal, or modification of the protective fencing shall only occur under the direction of a certified arborist and a written explanation of the reason for the relocation, removal, or modification of the protective fencing from the certified arborist must be provided to the City.”

b. “At the time of building permit, a site plan in compliance with the approved tree preservation and removal plan is required.”

c. “No excavation, grading, material storage, staging, vehicle parking or other construction activity shall take place within protective tree fencing areas.”

d. “The removal of trees not designated to be preserved is optional; removal may occur at the owner’s discretion.”

e. “Any tree designated for mitigation must be replaced with one tree selected from the approved species listed in Table 9.6885(2)(e)2 within one year from the date of removal or prior to final occupancy, whichever is later. At the time of planting, deciduous trees used for replacement must have a minimum diameter of 2 inches and evergreen trees used for replacement must be a minimum of 6 feet in height as measured according to the 2014 edition of the American Standard for Nursery Stock (ANSI Z60.1), published by the American Nursery and Landscape Association. Maintenance of replacement trees is the ongoing responsibility of the property owner.”

f. “In the event a tree designated to be preserved must be removed because it is dead, diseased, dying, or hazardous, documentation of the tree’s dead, diseased, dying, or hazardous condition by a certified arborist must be provided to the City prior to tree removal. The tree must be replaced with one replacement tree selected from the approved species list in Table 9.6885(2)(e)2. At the time of planting, deciduous trees used for replacement must have a minimum diameter of 2 inches and evergreen trees used for replacement must be a minimum of 6 feet in height as measured according to the 2014 edition of the American Standard for Nursery Stock (ANSI Z60.1), published by the American Nursery and Landscape Association. Maintenance of replacement trees is the ongoing responsibility of the property owner.”

(f) Street Tree Removal. If the proposal includes removal of any street tree(s), removal of those street trees has been approved, or approved with conditions according to the process at EC 6.305 Tree Felling Prohibition.