HomeMy WebLinkAboutTR_Arborist_Report_251102_v1CASCARA TREE CONSULTING
ARBORIST REPORT
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TO:
Thomas Chung
REFERENCE:
Tree Inventory & Arborist Report
SITE ADDRESS:
3607 NE 12th St, Renton, WA 98056 (Parcel #: 092305-9205)
DATE:
8/28/2025
PREPARED BY: Katie Hogan, ISA Certified Arborist PN-8078A
ISA Tree Risk Assessment Qualified
Scope of Work
This assessment was requested to ensure compliance with Renton Municipal Code (RMC) 4.4.130. The project
proposes subdividing the referenced site into three lots, with a detaching dwelling unit planned for each.
The site contains six trees measuring 6 inches or greater in Diameter at Breast Height (DBH), two of which
qualify as landmark trees1. Three of these trees are located in the future right-of-way (ROW) and therefore are
not included in the tree retention calculations. Per RMC 4.4.130(H), the project must retain at least 30% of
significant trees and either retain or replant enough trees to achieve a minimum of 30 tree credits per net acre.
For this 0.5-acre site, this equates to 15 tree credits (rounded down from 15.2). The project plans to remove all
qualifying significant trees and will replant to meet this requirement.
Observations & Discussion
Site Conditions
The property is a 28,160-square-foot (0.6-acre) R-8 zoned lot in the City of Renton. It currently contains a
dwelling unit, detached garage, and shed. The site is flat and, according to the City of Renton’s GIS Map,
contains no Environmentally Critical Areas (ECA). The project involves subdividing the parcel into three lots,
each with a detaching dwelling unit.
Existing Trees & Proposed Actions
There are three trees on the property with a DBH of 6 inches or more, one of which qualifies as a landmark tree.
Detailed tree information is provided in the attached Tree Table.
Tree Removals
• Tree #1: A 10.4-inch DBH horse chestnut (Aesculus hippocastanum), located at the center of proposed
Lot 3, is slated for removal to accommodate construction.
1 RMC 4.11.200: tree with a caliper of 24” or greater, except for bigleaf maples, black cottonwoods, and red alders which qualify at 30”
Arborist Report: Chung Short Plat - Renton
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• Tree #2: A 16-inch DBH Oregon ash (Fraxinus latifolia), located in proposed ‘Tract A’ (designated for
stormwater detention), is slated for removal.
• Tree #3: A 30-inch DBH Douglas-fir (Pseudotsuga menziesii), also in ‘Tract A’, is proposed for removal to
construct stormwater detention and frontage improvements.
Tree Retention & Protection
Trees #4-6 are planned for retention; however, due to their location in the future right-of-way, they do not
count toward the tree retention requirements for this project.
• Tree #4 & #6: Both Douglas-firs measuring 24 inches and 18 inches DBH, respectively, located at the
southwest corner of the property, will be retained and protected throughout site development.
Sidewalk construction to the east of the trees will impact approximately 3-7% of their driplines, a level
unlikely to affect long-term viability if protection fencing is maintained during site work.
• Tree # 5: An 11.3-inch DBH pacific dogwood (Cornus nuttallii) in the southwest corner will also be
retained. This tree will be protected beyond the dripline, with no anticipated impact.
Per RMC 4.4.130(10), a 6-foot-tall chain-link fence must be installed around the driplines of all retained trees.
Figure 1 shows recommended fencing location.
Figure 1. Recommended tree fencing (green line) for retained tree #s 4-6.
Arborist Report: Chung Short Plat - Renton
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Tree Retention & Credit Requirements
Under RMC 4.4.130(H), properties undergoing development must retain a minimum of 30% of significant trees
and meet the requirement of 30 tree credits per net acre. This project proposes to remove the three existing
significant trees and replant new trees to meet this requirement.
Table 1. Proposed Tree Retention
Total Existing Trees (6” DBH+) 6
Tree Deductions (ROW) 3
Remaining Significant Trees 3
Minimum Tree Retention Required (30%) 1
Trees Proposed for Retention 0
Proposed Tree Retention Rate 0%
Table 2. Proposed Tree Credits
Existing Significant Tree Credits 23.0
Tree Credits Required (30 /acre) 15
Total Tree Credits Retained 0
Proposed Replacement Trees (minimum) 15
Attachments
1) Site Map
2) Glossary
3) References
4) Inspection Methods
5) Appendix A – Assumptions & Limiting Conditions
6) Appendix B – Certification of Performance
7) Tree Table
Arborist Report: Chung Short Plat - Renton
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SITE MAP
Figure 2. Subject trees
Arborist Report: Chung Short Plat - Renton
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GLOSSARY
ANSI A300: American National Standards Institute (ANSI) standards for tree care
Chlorotic: discoloration caused by lack of chlorophyll in the foliage
Codominant Stems: two or more stems (or leaders) of relatively similar size that emerge from the same location
on the main trunk (Gilman, 2002)
Conifer: a tree that bears cones and has evergreen needles or scales
Crown: the above ground portion of the tree comprised of branches and their foliage
DBH or DSH: diameter at breast or standard height; the diameter of the trunk measured 54 inches (4.5 feet)
above grade
Deciduous: tree or other plant that loses its leaves annually and remains leafless generally during the cold
season
ISA: International Society of Arboriculture
Landscape function: the environmental, aesthetic, or architectural functions that a plant can have
Lateral: secondary or subordinate branch
Limits of disturbance: The boundary of minimum protection around a tree, the area that cannot be encroached
upon without possible permanent damage to the tree. It is a distance determined by a qualified professional and
is based on the age of the tree, its health, the tree species tolerance to disruption and the type of disturbance.
It also considers soil and environmental condition and previous impacts. It is unique to each tree in its location.
Owner/manager: the person or entity responsible for tree management or the controlling authority that
regulates tree management
Reaction wood: specialized secondary xylem which develops in response to a lean or similar mechanical stress,
it serves to help restore the stem to a vertical position
Significant tree: a tree measuring a specific diameter determined by the municipality the tree grows in. Some
municipalities deem that only healthy trees can be significant, other municipalities consider both healthy and
unhealthy trees of a determined diameter to be significant
Structural defects: flaws, decay, or other faults in the trunk, branches, or root collar of a tree, which may lead to
failure; may be genetic, or environmental
Tree credit: a number assigned to a tree by a municipality that may be equal to the diameter of the tree or a
numerical count of the tree, or related to diameter by a factor conveyed in a table of the municipal code
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) 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)
Arborist Report: Chung Short Plat - Renton
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REFERENCES
Dirr, Michael A. Manual of Woody Landscape Plants, Their Identification, Ornamental Characteristics, Culture,
Propagation, and Uses. Champaign: Stipes Publishing Company, 1990.
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, J. A. 2003. Preliminary Species Profiles for Tree Failure Assessment. Bowen Island: Dunster & Associates
Environmental Consultants Ltd.
Dunster, Julian A., E. Thomas Smiley, Nelda Matheny and Sharon Lilly. Tree Risk Assessment Manual.
Champaign, Illinois: International Society of Arboriculture, 2013.
Harris, Richard W, James Clark, and Nelda Matheny. Arboriculture, Integrated Management of Landscape Trees,
Shrubs, and Vines. 4th ed. Upper Saddle River: Prentice Hall, 2004.
Lilly, Sharon. Arborists’ Certification Study Guide. Champaign, IL: The International Society of Arboriculture,
2001.
Matheny, Nelda and Clark, James R. A Photographic Guide to the Evaluation of Hazard Trees in Urban Areas.
Second Edition. Champaign, IL: The International Society of Arboriculture, 1994.
Matheny, Nelda and Clark, James R. Trees and Development: A Technical Guide to Preservation of Trees During
Land Development. Champaign, IL: The International Society of Arboriculture, 1998.
Mattheck, Claus and Breloer, Helge. The Body Language of Trees: A Handbook for Failure Analysis. London:
HMSO, 1994
Schwarze, Francis W.M.R. Diagnosis and Prognosis of the Development of Wood Decay in Urban Trees. Australia:
ENSPEC Pty Ltd. 2008
Sinclair, Wayne A., Lyon, Howard H., and Johnson, Warren T. Diseases of Trees and Shrubs. Ithaca, New York:
Cornell University Press, 1987.
Smiley, E. Thomas, Nelda Matheny, and Sharon Lilly. Tree Risk Assessment Best Management Practices, ANSI
A300 Part 9: Tree, Shrub, and Other Woody Plant Management—Standard Practices (Tree Risk Assessment: Tree
Structure Assessment). The International Society of Arboriculture Press. Champaign. IL. 2011.
Thies, Walter G. and Sturrock, Rona N. Laminated root rot in Western North American. United States
Department of Agriculture. Pacific Northwest. Resource Bulletin PNW-GTR-349. April 1995.
Arborist Report: Chung Short Plat - Renton
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INSPECTION METHODS
I utilized existing data collected from the previous arborist, as well as aerial and street view imagery, to
determine the condition of each tree. Tree health and structure are each assigned their own condition rating.
The following ratings are used:
Poor: Lacking a full crown, with more than 50% decline and dieback that especially affects larger branches.
Low life expectancy for the species.
Fair: Crown decline and dieback up to 30% of the canopy. Below-average life expectancy for the species.
Good: Imperfect canopy density in 10% or less of the tree. Typical life expectancy for the species.
Excellent: Perfect specimen with excellent form and vigor, along with a well-balanced crown. Exceptional
life expectancy for the species.
Arborist Report: Chung Short Plat - Renton
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APPENDIX A - ASSUMPTIONS & LIMITING CONDITIONS
1) Any legal description provided to the consultant/appraiser is assumed to be correct. Any titles and
ownerships to any property are assumed to be good and marketable. No responsibility is assumed for
matters legal in character. Any and all property is appraised or evaluated as though free and clear, under
responsible ownership and competent management.
2) It is assumed that any property is not in violation of any applicable codes, ordinances, statutes or other
governmental regulations.
3) The assessment in this report is based on information and data from sources believed to be reliable,
correct, and accurately reported. No responsibility is assumed for false or misleading information provided
by others.
4) The consultant/appraiser shall not be required to give testimony or to attend court by reason of the report
unless subsequent contractual arrangements are made including payment of an additional fee for such
services as described in the fee schedule and contract of engagement.
5) Loss or alteration of any part of this report invalidates the entire report.
6) Possession of this report or a copy thereof does not imply right of publication or use for any purpose by any
other than the person to whom it is addressed, without the prior expressed written or verbal consent of
the consultant/appraiser.
7) Neither all nor any part of the contents of the report, nor copy thereof, shall be conveyed by anyone,
including the client to the public through advertising, public relations, news, sales or other media, without
the prior expressed written or verbal consent of the consultant/appraiser – particularly as to value
conclusions, identity of the consultant/appraiser, or any reference to any professional society or instate or
to any initialed designation conferred upon the consultant/appraiser as stated in her qualification.
8) The report and any values expressed herein represent the opinion of the consultant/appraiser, and the
consultant’s/appraiser’s fee is in no way contingent upon the reporting of a specified value, a stipulated
result, the occurrence of subsequent event, nor upon any finding to be reported.
9) Sketches, diagrams, graphs, and photographs in this report, being intended as visual aid, are not necessarily
to scale and should not be construed as engineering or architectural reports or survey.
10) Unless expressed otherwise: 1) information contained in this report covers only those items that were
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 or coring. There is
not warranty or guarantee, expressed or implied, that problems or deficiencies of the plants or property in
question may not arise in the future.
Arborist Report: Chung Short Plat - Renton
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APPENDIX B - CERTIFICATION OF PERFORMANCE
I, Katie Hogan, certify that:
• I have personally inspected the trees on the property referenced in this report and the statements of
fact contained in this report are true and correct.
• I have no present or prospective interest in the property that is the subject of this report, and I have no
personal interest with respect to the parties involved.
• The reported analysis, opinions, and conclusions are my personal, unbiased professional analysis,
opinions, and conclusions.
• My analysis, opinions, and conclusions were developed, and this report has been prepared according to
commonly accepted arboricultural best practices.
• No individuals or organizations have provided significant assistance with the preparation of this report,
except those named in the report.
• My compensation for completing this assignment is not contingent upon the development or reporting
of a predetermined outcome or direction that favors the cause of the client, the results of the
assessment, or the occurrence of any subsequent events.
Signed:
Cascara Tree Consulting, LLC
Client: Thomas Chung
Address: 3607 NE 12th St, Renton, WA
8/28/2025
Tree Inventory Table Prepared By: Cascara Tree Consulting
[PN-8078A, TRAQ]
Tree
No.
Species Common
Name
Adjusted
DBH (in)
Multistem
DBH (in)
Health
Rating
Structural
Rating
Viable
(Yes/No)
Dripline
Radius (ft)
Designation Tree Credits Deductions Retain/
Remove
Notes
1 Aesculus
hippocastanum
Horse
chestnut
10.4 6,6,6 Good Good Yes 14.0 Significant 5.0 No Remove
2 Fraxinus latifolia Oregon ash 16.0 Good Good Yes 20.0 Significant 7.0 No Remove
3 Pseudostuga
menziesii
Douglas-fir 30.0 Good Fair Yes 24.0 Landmark 11.0 No Remove Previously topped with multiple
trunks
4 Pseudostuga
menziesii
Douglas-fir 24.0 Good Good Yes 17.0 Landmark N/A (ROW) Yes Retain Located along property line
5 Cornus nuttallii Pacific
dogwood
11.3 8,8 Good Good Yes 12.0 Significant N/A (ROW) Yes Retain Located along property line
6 Pseudostuga
menziesii
Douglas-fir 18.0 Good Good Yes 12.0 Significant N/A (ROW) Yes Retain Located along property line
6
3
3
1
0
0%
23.0
15.2
0.0
Proposed Tree Retention (%)
Total Existing Significant Trees
Total Existing Tree Credits
Total Tree Credits Required (30/acre)
Total Tree Credits Retained
Minimum Tree Retention Required (30%)
Trees Proposed to Retain
Deductions (ROW Trees)
Total Trees after Deductions
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