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2940 Westlake Ave. N (Suite #200) ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
Project No. TS ‐ 7543
Arborist Report
TO: Fazio Associates, LLC
SITE: 900 NE 10th St, Renton, WA 98056 (Parcel #: 7227900075)
RE: Tree Inventory
DATE: February 1, 2021
PROJECT ARBORIST: Katie Hogan
ISA Certified Arborist #PN‐ 8078A
ISA Qualified Tree Risk Assessor
REVIEWED BY: Josh Petter
ISA Certified Arborist #PN‐ 8406A
ISA Qualified Tree Risk Assessor
REFERENCED PLANS: SMR Architects – Preliminary Site Plan: Sheets A001, A101‐A105
Fazio Associates Inc – Tree Retention Plan
ATTACHED: Table of Trees
Summary
Tree Solutions assessed 19 trees at the above addressed job site. Of these trees assessed, none are
considered landmark trees. A significant tree is defined as a tree measuring 6 inches Diameter at
Standard Height (DSH) or greater and a landmark tree is a tree with a DSH of 30 inches or greater.1
Five trees located off‐site with canopies overhanging the site were also assessed, all of which are located
in a private access easement along the east side of the site. Off‐site trees are noted in this report using
alphabetical identifiers.
Assignment & Scope of Report
This report outlines the site inspection by Katie Hogan, of Tree Solutions Inc, on January 7, 2021. I was
asked to visit the site and assess significant trees. I was asked to produce an Arborist Report
documenting my findings and management recommendations. Rob Fazio, landscape architect for the
project, requested these services for project planning.
Specifics for each tree can be found in the attached Table of Trees. Photographs, a glossary and list of
references follow the report. Assumptions and limiting conditions can be found in Appendix A. Methods
can be found in Appendix B.
1 Renton Municipal Code. 4‐11‐200. Definitions
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 2 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
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Observations
The Site and History
The 55,757 square foot site fronts NE 10th St in the City of Renton. One office building with associated
parking currently exists on site. This property is located in the Center Village Zoning (CV). No
environmental critical areas (ECAs) exist on site according to City of Renton and King County I‐Map GIS
databases. The site is manicured and the majority of vegetation exists around the perimeter of the site.
The Trees
The tree species on‐site consisted of non‐native and ornamental tree species including: Scots pine (Pinus
sylvestris), cherry plum (Prunus cerasifera), flowering cherry (Prunus serrulata), and Japanese zelkova
(Zelkova serrata). Specifics for each tree can be found in the attached Table of Trees.
All of the trees were generally in good to fair health and structural condition. Most of the trees
appeared to have been heavily managed over the years. Soils on the site were shallow and compacted,
resulting in visible surface roots from most trees and impacts from roots to surrounding hardscapes. I
observed cracking and lifting of both the parking lot and adjacent sidewalks which appeared to be from
tree roots.
Discussion – Preliminary Construction Impacts
Based on preliminary plans, the property line will be adjusted to meet city requirements for ROW
dedications and improvements. This will result in a larger ROW and reduced square footage for the
subject private property. As a result, the majority of the trees located along the south (NE 10th St) and
west (Jefferson Ave NE) perimeters of the site will require removal. Improvements to the ROW include
the addition of a parking lane, bike lane, 6‐inch curb, 8‐foot planting strip, and 8‐foot sidewalk.
There are three trees located at the interior of the site (Trees 7, 18, 19) that will also likely require
removal to accommodate the new buildings, parking, and site grading.
A rockery currently exists along the southeast/east side of the property that is proposed for removal and
replacement to maintain flat grading on the interior of the site. Trees B, C, D, E are growing atop the
existing rockery. These trees will likely require removal to demolish and re‐construct the retaining wall
on the east side of the property. Due to the shallow surface roots visible around these trees and close
proximity to the rockery, it is likely the trees have roots occupying the space where the rockery will be
removed and that tree retention may not be feasible.
Tree Retention and Replacement
Ten percent of significant trees must be retained on sites zoned as CV2. As an alternative to retaining
trees, the Administrator may authorize the planting of replacement trees on the site if it can be
demonstrated to the Administrator’s satisfaction that an insufficient number of trees can be retained.
When the required number of protected trees cannot be retained, replacement trees, with at least a
two‐inch (2") caliper or an evergreen at least six feet (6') tall, shall be planted at a rate of twelve (12)
caliper inches of new trees to replace each protected tree removed. Up to fifty percent (50%) of trees
2 Renton Municipal Code. 4‐4‐130. PERFORMANCE STANDARDS FOR LAND DEVELOPMENT/BUILDING PERMITS.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 3 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
required pursuant to RMC 4‐4‐070, Landscaping, may contribute to replacement trees. The City may
require a surety or bond to ensure the survival of replacement trees3.
Recommendations
Add tree numbers and dripline per Tree Solutions Table of Trees to all plans.
Respectfully submitted,
Katie Hogan
3 Renton Municipal Code. 4‐4‐070. Landscaping.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 4 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
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Photographs
Photo 1: Looking north at trees located at northwest corner of site.
Photo 2: Looking east toward Tree A located in private access easement.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 5 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
Photo 3. Surface roots, typical throughout site.
Photo 4. Trees located in private access easement growing atop the rock retaining wall.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 6 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
Photo 5. Damages to hardscapes from roots, typical throughout site.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 7 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
Photo 6. Scots pine trees along west side of site, typical conditions.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 8 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
Photo 7. Tree 19 located at the interior of site.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 9 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
Glossary
ANSI A300: American National Standards Institute (ANSI) standards for tree care
basic assessment: detailed visual inspection of a tree and surrounding site that may include the use of
simple tools. It requires that a tree risk assessor walk completely around the tree trunk looking at
the site, aboveground roots, trunk, and branches (ISA 2013)
codominant stems: stems or branches of nearly equal diameter, often weakly attached (Matheny et al.
1998)
cracks: defects in trees that, if severe, may pose a risk of tree or branch failure (Lilly 2001)
crown: the aboveground portions of a tree (Lilly 2001)
DBH or DSH: diameter at breast or standard height; the diameter of the trunk measured 54 inches (4.5
feet) above grade (Matheny et al. 1998)
force: any action or influence causing an object to accelerate/decelerate. Calculated as mass multiplied
by acceleration. Is a vector quantity (ISA 2013)
ISA: International Society of Arboriculture
included bark: bark that becomes embedded in a crotch between branch and trunk or between
codominant stems and causes a weak structure (Lilly 2001)
lateral: secondary or subordinate branch (Lilly 2001)
level(s) of assessment: categorization of the breadth and depth of analysis used in an assessment (ISA
2013)
lever arm: the distance between the applied force (or center of force) and the point where the object
will bend or rotate (ISA 2013)
limited visual assessment: a visual assessment from a specified perspective such as foot, vehicle, or
aerial (airborne) patrol of an individual tree or a population of trees near specified targets to identify
specified conditions or obvious defects (ISA 2013)
mitigation: process of reducing damages or risk (Lilly 2001)
monitoring: keeping a close watch; performing regular checks or inspections (Lilly 2001)
owner/manager: the person or entity responsible for tree management or the controlling authority
that regulates tree management (ISA 2013)
pathogen: causal agent of disease (Lilly 2001)
retain and monitor: the recommendation to keep a tree and conduct follow‐up assessments after a
stated inspection interval (ISA 2013)
significant size: a tree measuring 6” DSH or greater
snag: a tree left partially standing for the primary purpose of providing habitat for wildlife
structural defects: flaws, decay, or other faults in the trunk, branches, or root collar of a tree, which
may lead to failure (Lilly 2001)
Visual Tree Assessment (VTA): method of evaluating structural defects and stability in trees by noting
the pattern of growth. Developed by Claus Mattheck (Harris, et al 1999)
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 10 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
References
ANSI A300 (Part 1) – 2008 American National Standards Institute. American National Standard for Tree
Care Operations: Tree, Shrub, and Other Woody Plant Maintenance: Standard Practices (Pruning).
New York: Tree Care Industry Association, 2008.
Dunster & Associates Environmental Consultants Ltd. Assessing Trees in Urban Areas and the Urban‐
Rural Interface, US Release 1.0. Silverton: Pacific Northwest Chapter ISA, 2006
Dunster, Julian A., E. Thomas Smiley, Nelda Matheny, and Sharon Lilly. Tree Risk Assessment Manual.
Champaign, Illinois: International Society of Arboriculture, 2013
E. Smiley, N. Matheny, S. Lilly. Best Management Practices: TREE RISK ASSESSMENT. ISA 2011.
Lilly, Sharon. Arborists’ Certification Study Guide. Champaign, IL: The International Society of
Arboriculture, 2001.
Matheny, Nelda and James R. Clark. Trees and Development: A Technical Guide to Preservation of Trees
During Land Development. Champaign, IL: International Society of Arboriculture, 1998.
Mattheck, Claus and Helge Breloer, The Body Language of Trees.: A Handbook for Failure Analysis.
London: HMSO, 1994.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 11 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
Appendix A ‐ Assumptions & Limiting Conditions
1. Consultant assumes that the site and its use do not violate, and is in compliance with, all applicable
codes, ordinances, statutes or regulations.
2. The consultant may provide a report or recommendation based on published municipal regulations.
The consultant assumes that the municipal regulations published on the date of the report are
current municipal regulations and assumes no obligation related to unpublished city regulation
information.
3. Any report by the consultant and any values expressed therein represent the opinion of the
consultant, and the consultant’s fee is in no way contingent upon the reporting of a specific value, a
stipulated result, the occurrence of a subsequent event, or upon any finding to be reported.
4. All photographs included in this report were taken by Tree Solutions, Inc. during the documented
site visit, unless otherwise noted. Sketches, drawings and photographs (included in, and attached to,
this report) are intended as visual aids and are not necessarily to scale. They should not be construed
as engineering drawings, architectural reports or surveys. The reproduction of any information
generated by architects, engineers or other consultants and any sketches, drawings or photographs
is for the express purpose of coordination and ease of reference only. Inclusion of such information
on any drawings or other documents does not constitute a representation by the consultant as to
the sufficiency or accuracy of the information.
5. Unless otherwise agreed, (1) information contained in any report by consultant covers only the items
examined and reflects the condition of those items at the time of inspection; and (2) the inspection
is limited to visual examination of accessible items without dissection, excavation, probing, climbing,
or coring.
6. These findings are based on the observations and opinions of the authoring arborist, and do not
provide guarantees regarding the future performance, health, vigor, structural stability or safety of
the plants described and assessed.
7. Measurements are subject to typical margins of error, considering the oval or asymmetrical cross‐
section of most trunks and canopies.
8. Tree Solutions did not review any reports or perform any tests related to the soil located on the
subject property unless outlined in the scope of services. Tree Solutions staff are not and do not claim
to be soils experts. An independent inventory and evaluation of the site’s soil should be obtained by
a qualified professional if an additional understanding of the site’s characteristics is needed to make
an informed decision.
9. Our assessments are made in conformity with acceptable evaluation/diagnostic reporting techniques
and procedures, as recommended by the International Society of Arboriculture.
Arborist Report: Sunset Gardens, Renton
February 1, 2021 page 12 of 12
2940 Westlake Ave. N #200 ∙ Seattle, WA 98109 ∙ Phone 206.528.4670
www.treesolutions.net
Appendix B ‐ Methods
I evaluated tree health and structure utilizing visual tree assessment (VTA) methods. The basis behind
VTA is the identification of symptoms, which the tree produces in reaction to a weak spot or area of
mechanical stress. A tree reacts to mechanical and physiological stresses by growing more vigorously to
reinforce weak areas, while depriving less stressed parts (Mattheck & Breloer 1994). An understanding
of the uniform stress allows me to make informed judgments about the condition of a tree.
I measured the diameter at standard height (DSH) of each tree, typically at 54 inches above grade.
If a tree had multiple stems, I measured each stem individually at standard height and determined a
single‐stem equivalent diameter by taking the average of the stem diameters, as established by the
Guide for Plant Appraisal, 10th Edition.
Tree health considers crown indicators including foliar density, size, color, stem shoot extensions, decay,
and damage. We have adapted our ratings based on the Purdue University Extension Formula Values for
health condition. These values are a general representation used to assist in arborists in assigning ratings.
Tree health needs to be evaluated on an individual basis and may not always fall entirely into a single
category, however, I assigned a single condition rating for ease of clarity.
Excellent
Perfect specimen with excellent form and vigor, well‐balanced crown. Normal to exceeding shoot length
on new growth. Leaf size and color normal. Trunk is sound and solid. Root zone undisturbed. No apparent
pest problems. Long safe useful life expectancy for the species.
Good
Imperfect canopy density in few parts of the tree, up to 10 percent of the canopy. Normal to less than ¾
of typical growth rate of shoots and minor deficiency in typical leaf development. Few pest issues or
damage, and if they exist they are controllable or tree is reacting appropriately. Normal branch and stem
development with healthy growth. Safe useful life expectancy typical for the species.
Fair
Crown decline and dieback up to 30 percent of the canopy. Leaf color is somewhat chlorotic/necrotic with
smaller leaves and “off” coloration. Shoot extensions indicate some stunting and stressed growing
conditions. Stress cone crop is clearly visible. Obvious signs of pest problems contributing to a lesser
condition. Control might be possible. I found some decay areas in the main stem and branches. Below
average safe useful life expectancy
Poor
Lacking full crown, more than 50 percent decline and dieback, especially affecting larger branches.
Stunting of shoots is obvious with little evidence of growth on smaller stems. Leaf size and color reveals
overall stress in the plant. Insect or disease infestation may be severe and uncontrollable. Extensive decay
or hollows in branches and trunk. Short safe useful life expectancy.
Tree health condition ratings have been adapted from the Purdue University Extension bulletin FNR‐473‐
W ‐ Tree Appraisal
Table of TreesSunset Gardens900 NE 10th St, Renton, WAArborist: K. HoganDate of Inventory: 01.07.2021Table Prepared: 02.01.2021DSH (Diameter at Standard Height) is measured 4.5 feet above grade, or as specified in the Guide for Plant Appraisal, 10th Edition, published by the Council of Tree and Landscape Appraisers.DSH for multi‐stem trees are noted as a single stem equivalent, which is calculated using the method defined in the Guide for Plant Appraisal, 10th EditionAny tree planted in the last 10 years is considered significant regardless of sizeLetters are used to identify trees on neighboring properties with overhanging canopies.Dripline is measured from the center of the tree to the outermost extent of the canopy.Tree ID Location Scientific Name Common NameDSH (inches)DSH MultistemHealth ConditionStructural ConditionDripline Radius (feet)Landmark Designation Notes1SitePinus sylvestrisScots pine 17.8 Good Fair 15.7‐Surface roots, narrow codominant union, lifting pavement to east2SitePinus sylvestrisScots pine 13.0 Good Good 11.5‐Surface roots3SitePrunus cerasifera Cherry plum 10.2 Good Good 15.4‐Surface roots4SitePrunus cerasifera Cherry plum 12.4 Good Good 15.5‐Pavement lifting to south5SitePrunus cerasifera Cherry plum 15.0 10.3,7.5,8 Good Fair 13.6‐Narrow unions, trunk grafting6SitePrunus cerasifera Cherry plum 10.1 Good Good 10.4‐Surface roots7SitePinus sylvestrisScots pine 7.8 Good Good 6.3‐Bowed trunk8SitePrunus serrulata Flowering cherry 15.4 Fair Fair 15.1‐Surface roots, pavement lifting9SitePinus sylvestrisScots pine 18.5 Good Good 12.8‐Surface roots, old pruning wounds, pavement lifting10 SitePinus sylvestrisScots pine 16.8 Fair Fair 12.7‐Canopy dieback to east, pitch moth activity, narrow trunk union11 SitePinus sylvestrisScots pine 11.8 Good Good 10.5‐Pitch moth, pavement lifting12 SitePinus sylvestrisScots pine 11.5 Good Good 9.5‐Pitch moth, pavement lifting13 SitePinus sylvestrisScots pine 12.7 Good Good 15.0‐Pitch moth, pavement lifting14 SitePinus sylvestrisScots pine 14.0 Good Fair 12.6‐Multiple narrow unions15 SitePinus sylvestrisScots pine 8.0 Fair Good 11.3‐Flush cuts, suppressed16 SitePinus sylvestrisScots pine 12.1 Good Fair 9.0‐Flush cuts, multiple unions, pitch moth17 SitePinus sylvestrisScots pine 14.7 Good Fair 16.1‐Sidewalk lifting, parking lot lifting, narrow trunk junctions18 SitePrunus serrulata Flowering cherry 14.7 Fair Fair 15.1‐Poor trunk architecture, compacted soils19 SitePrunus serrulata Flowering cherry 13.2 Fair Fair 10.1‐Canopy decline, lean, surface roots, pavement crackingTrees 30" or greater DSH are considered Landmark treesTrees on the King County Weed List are not considered treesTrees considered dangerous are not considered significantSignificant trees are 6" or greater DSH , except for cottonwood and alder, which are 8" or greater DSHTree Solutions, Inc.2940 Westlake Ave. N #200 Seattle, WA 98109Page 1 of 2www.treesolutions.net206‐528‐4670
Table of TreesSunset Gardens900 NE 10th St, Renton, WAArborist: K. HoganDate of Inventory: 01.07.2021Table Prepared: 02.01.2021Tree ID Location Scientific Name Common NameDSH (inches)DSH MultistemHealth ConditionStructural ConditionDripline Radius (feet)Landmark Designation NotesAPrivate Access EasementZelkova serrataJapanese zelkova 14.8 Good Fair 17.6‐Narrow codominant unions, private access easement tree, surface roots. Does not count toward retention percentage for siteBPrivate Access EasementZelkova serrataJapanese zelkova 11.6 Good Good 12.5‐Surface roots, narrow codominant unions, private access easement treeCPrivate Access EasementZelkova serrataJapanese zelkova 8.5 Good Good 10.4‐Private access easement treeDPrivate Access EasementZelkova serrataJapanese zelkova 10.6 Good Good 12.4‐Private access easement tree, surface rootsEPrivate Access EasementZelkova serrataJapanese zelkova 11.3 Good Good 15.5‐Private access easement treeTree Solutions, Inc.2940 Westlake Ave. N #200 Seattle, WA 98109Page 2 of 2www.treesolutions.net206‐528‐4670