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11415 NE 128th St., Suite 110, Kirkland, WA 98034 | Phone: 425.820.3420 | Fax: 425.820.3437
americanforestmanagement.com
ARBORIST REPORT for 4512 Talbot Road S Renton, WA
January 2, 2019
American Forest Management 1/2/2019
Table of Contents
1. Introduction .............................................................................................................. 1 2. Description ............................................................................................................... 1
3. Methodology ............................................................................................................ 1
4. Observations ........................................................................................................... 1 5. Discussion ............................................................................................................... 2
6. Tree Protection Measures ........................................................................................ 3
7. Tree Replacement ................................................................................................... 4
Appendix
Site/Tree Photos – pages 5 – 8
Tree Summary Table – attached Tree Conditions Map - attached
General Tree Protection Fencing Detail - attached
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1. Introduction
American Forest Management, Inc. was contacted by Ed Pozniak of Architectural Innovations, and was asked
to compile an ‘Arborist Report’ for a property located within the City of Renton. The proposed remodel/addition project encompasses property located at 4512 Talbot Road. Our assignment is
to prepare a written report on present tree conditions, which is to be filed with the preliminary permit application.
This report encompasses all of the criteria set forth under City of Renton code section 4-8-120. The property is zoned commercial requiring 10% of the significant trees be retained.
Date of Field Examination: December 3, 2018
2. Description
Eight significant trees were identified and assessed on the property. These are comprised of a mix of planted
coniferous ornamental species. A numbered aluminum tag was placed on the lower trunks of the subject trees, approximately 6 feet above ground. These tag numbers correspond with the numbers on the Tree Summary Table and attached map.
There are no significant concerns regarding neighboring trees to the south, adjacent to the proposed
improvements. There are five planted street trees (sweetgum) adjacent to Talbot Road at the front of the property. The property to the east is comprised of several problematic black cottonwood trees.
3. Methodology
Each tree in this report was visited. Tree diameters were measured by tape. The tree heights were measured
using a Spiegel Relaskop. Each tree was visually examined for defects and vigor. The tree assessment procedure involves the examination of many factors:
• The crown of the tree is examined for current vigor. This is comprised of inspecting the crown (foliage, buds and branches) for color, density, form, and annual shoot growth, limb dieback and
disease. The percentage of live crown is estimated for coniferous species only and scored appropriately.
• The bole or main stem of the tree is inspected for decay, which includes cavities, wounds, fruiting bodies of decay (conks or mushrooms), seams, insects, bleeding, callus development, broken or dead
tops, structural defects and unnatural leans. Structural defects include crooks, forks with V-shaped
crotches, multiple attachments, and excessive sweep.
• The root collar and roots are inspected for the presence of decay, insects and/or damage, as well as if
they have been injured, undermined or exposed, or original grade has been altered.
Based on these factors a determination of condition is made. A ‘viable’ tree is “A significant tree that a qualified professional has determined to be in good health, with a low risk of failure due to structural
defects, is wind firm if isolated or remains as part of a grove, and is a species that is suitable for its location.” Trees considered ‘non-viable’ are trees that are in poor condition due to disease and/or pests, age
related decline, have significant decay issues and/or cumulative structural defects, which exacerbate failure potential.
The three condition categories are described below:
Good – free of significant structural defects, no disease concerns, minor pest issues, no significant root
issues, good structure/form with uniform crown or canopy, foliage of normal color and density, average or
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normal vigor, will be wind firm if isolated or left as part of a grouping or grove of trees, suitable for its
location
Fair – minor to moderate structural defects not expected to contribute to a failure in near future, no disease concerns, moderate pest issues, no significant root issues, asymmetric or unbalanced crown or canopy, average or normal vigor, foliage of normal color, moderate foliage density, will be wind firm if left as part
of a grouping or grove of trees, cannot be isolated, suitable for its location
Poor – major structural defects expected to cause fail in near future, disease or significant pest concerns, decline due to old age, significant root issues, asymmetric or unbalanced crown or canopy, sparse or
abnormally small foliage, poor vigor, not suitable for its location
The attached Tree Summary Table provides specific information on tree sizes, condition and drip-line measurements.
4. Observations
Eight significant trees were identified within the parcel boundaries. The subject trees are comprised of a mix of planted evergreen or coniferous species. These include Austrian or black pine and Deodar cedar.
The on-site trees to be retained include two Austrian pine, Trees #1 and #2. Both of these are in fairly good condition. Foliage is of normal color and density. Both have a forked main trunk. The forked attachment on
Tree #1 is sound. The forked attachment on Tree #2 is a weaker, ‘V’-shaped attachment. See pictures below.
The remaining on-site trees comprise a small grove of Deodar cedar and Austrian pine. These are situated
where the existing building will be expanded. The neighboring property east of the existing building is covered with volunteer native black cottonwood trees. These are mostly young to semi-mature specimens which have developed very poor trunk taper as they compete
with each other for sunlight and space. The majority also has an English ivy infestation where the ivy has climbed several feet up the trunks. See pictures below.
The neighboring property to the south is vacant and naturally vegetated. Tree cover is primarily made up of
Scouler’s willow, a short-lived native willow species.
There are five semi-mature sweetgum trees adjacent to Talbot Road at the front of the property. These have developed typical form for the species. Many have forked tops with weak ‘V’-shaped attachments, common for the species. Tree #101 has a significant lean to the northwest. There is a rope tied around the trunk. Roots from Trees #104 and #105 have lifted the sidewalk, creating a tripping hazard.
There are two neighboring Western red cedar trees (#107 and #9) and a semi-mature red maple (#106) on the
adjacent property to the north. Tree #9 is situated close to the property line. Both cedars are in fair to good condition with no concerning defects. The red maple is in fair condition with some decay in the lower trunk
and a fork of the trunk with included bark.
5. Discussion
The measured drip-lines (farthest reaching branches) for the subject trees can be found on the attached Tree Summary Table. These have also been delineated on a copy of the attached survey for trees proposed for
retention. The information plotted on the attached plan may need to be transferred to a final tree retention/protection plan to meet City submittal requirements. The trees that are to be removed shall be shown
“X’d” out on the final plan.
The Limits of Disturbance (LOD) measurements can also be found on the tree summary table. This is the recommended distance of the closest impact (soil excavation or fill) to the trunk face. These should be
referenced when determining tree retention feasibility. The LOD measurements are based on species, age,
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condition, drip-line, prior improvements, proposed impacts and the anticipated cumulative impacts to the entire
root zone.
Tree protection fencing shall be located a few feet beyond the drip-line edge of retained trees as shown per the attached plan. In order to properly protect retained trees, existing grades shall be maintained around them to the
fullest extent possible. There is adequate space to successfully preserve Tree #1 and Tree #2. Tree #2 has a problematic fork of the trunk. Over time, the forked attachment will likely grow weaker as the tree matures. The installation of a cable in the crown of the tree is recommended to reduce the risk of a forked stem failure.
Sweetgum trees are notorious for lifting asphalt and concrete. This species develops very large surface roots. The sidewalk is already being lifted at the north end of the row. More lifting and possibly cracking is expected
in the future, given the proximity of the trees to the sidewalk. Given the relatively small size of the subjects,
any encroaching roots can be pruned away to appropriately repair the sidewalk. Because sweetgum trees have very shallow root systems, a new sidewalk constructed east of the trees is not recommended. If the right-of-way
is to be improved as part of this project, it would be prudent to remove the sweetgum trees and re-landscape the area with new trees post any improvements. The neighboring cottonwood trees on the property to the east are problematic. There is a high probability of
tree failures in this area in the near future. These trees have developed very poor stem taper. The poor taper in combination with the weight of the ivy will cause these trees to fail at some point. Any of these cottonwood
trees that lean toward the building should be removed in the near future.
No significant impacts are anticipated for the neighboring trees to the north, if the work zone is limited to the edge of the asphalt or curb line.
Finished landscaping work within the drip-lines of retained trees shall maintain existing grades and not disturb fine root mass at the ground surface. Finish landscape with mulch or new lawn on top of existing grade. Add no more than 2” to 4” of mulch or 2” of composted soil to establish new lawn. Raising the grade more than a few
inches will have adverse impacts on fine roots by cutting off oxygen causing suffocation.
6. Tree Protection Measures
The following general guidelines are recommended to ensure that the designated space set aside for the preserved trees are protected and construction impacts are kept to a minimum.
1. Tree protection fencing should be erected around retained trees and positioned just beyond the drip-line edge prior to moving any heavy equipment on site. Doing this will set clearing limits and avoid compaction of soils
within root zones of retained trees.
2. Any existing infrastructure to be removed within the drip-line or tree protection zone shall be removed by hand or utilizing a tracked mini-excavator.
3. Excavation limits should be laid out in paint on the ground to avoid over excavating.
4. Excavations within the drip-lines shall be monitored by a qualified tree professional so necessary precautions
can be taken to decrease impacts to tree parts. A qualified tree professional shall monitor excavations when work is required and allowed within the “limits of disturbance”.
5. To establish sub grade for foundations, curbs and pavement sections near the trees, soil should be removed
parallel to the roots and not at 90 degree angles to avoid breaking and tearing roots that lead back to the trunk within the drip-line. Any roots damaged during these excavations should be exposed to sound tissue and cut
cleanly with a saw. Cutting tools should be sterilized with alcohol.
6. Areas excavated within the drip-line of retained trees should be thoroughly irrigated weekly during dry periods.
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7. Preparations for final landscaping shall be accomplished by hand within the drip-lines of retained trees.
Large equipment shall be kept outside of the tree protection zones at all times. Simply finish landscape within
10’ of retained trees with a 2” to 4” layer of organic mulch.
City Code Regarding Tree Protection RMC 4-4-130 H. 9. Protection Measures During Construction: Protection measures in this subsection shall apply for all trees that are to be retained on site and off site. Off-site trees containing drip lines that encroach
onto the site under construction shall be considered protected trees unless it is determined the abutting property owner is in compliance with subsection C of this Section, Allowed Tree Removal Activities. All of the following tree protection measures shall apply:
a. Construction Storage Prohibited: The applicant may not fill, excavate, stack or store any equipment, dispose of any materials, supplies or fluids, operate any equipment, install impervious surfaces, or compact the earth in
any way within the area defined by the drip line of any tree to be retained. b. Fenced Protection Area Required: Prior to development activities, the applicant shall erect and maintain six-foot (6') high chain link temporary construction fencing around the drip lines of all retained trees or at a distance
surrounding the tree equal to one and one-quarter feet (1-1/4') for every one inch (1") of trunk caliper, whichever is greater, or along the perimeter of a tree protection tract. Placards shall be placed on fencing every
fifty feet (50') indicating the words, “NO TRESPASSING – Protected Trees,” or on each side of the fencing if less than fifty feet (50'). Site access to individually protected trees or groups of trees shall be fenced and signed.
Individual trees shall be fenced on four (4) sides. In addition, the applicant shall provide supervision whenever equipment or trucks are moving near trees.
c. Protection from Grade Changes: If the grade level adjoining to a tree to be retained is to be raised, the applicant shall construct a dry rock wall or rock well around the tree. The diameter of this wall or well must be equal to the tree’s drip line.
d. Impervious Surfaces Prohibited within the Drip Line: The applicant may not install impervious surface
material within the area defined by the drip line of any tree to be retained.
e. Restrictions on Grading within the Drip Lines of Retained Trees: The grade level around any tree to be retained may not be lowered within the greater of the following areas: (i) the area defined by the drip line of the
tree, or (ii) an area around the tree equal to one and one-half feet (1-1/2') in diameter for each one inch (1") of tree caliper. A larger tree protection zone based on tree size, species, soil, or other conditions may be required.
(Ord. 5676, 12-3-2012)
f. Mulch Layer Required: All areas within the required fencing shall be covered completely and evenly with a minimum of three inches (3") of bark mulch prior to installation of the protective fencing. Exceptions may be
approved if the mulch will adversely affect protected ground cover plants. (Ord. 5676, 12-3-2012)
g. Monitoring Required during Construction: The applicant shall retain a certified arborist or licensed landscape architect to ensure trees are protected from development activities and/or to prune branches and roots, fertilize,
and water as appropriate for any trees and ground cover that are to be retained.
h. Alternative Protection: Alternative safeguards may be used if determined to provide equal or greater tree protection. (Ord. 5676, 12-3-2012; Ord. 5841, 6-12-2017)
7. Tree Replacement
New or supplemental trees will not likely be needed to meet code since 25% of the significant trees are being
retained. However, new tree plantings may be desired to enhance the new landscape. New tree plantings shall be given the appropriate space for the species and their growing characteristics.
For planting and maintenance specifications, refer to municipal code 4-4-070 Landscaping.
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There is no warranty suggested for any of the trees subject to this report. Weather, latent tree conditions, and
future man-caused activities could cause physiologic changes and deteriorating tree condition. Over time,
deteriorating tree conditions may appear and there may be conditions, which are not now visible which, could
cause tree failure. This report or the verbal comments made at the site in no way warrant the structural stability
or long term condition of any tree, but represent my opinion based on the observations made.
Nearly all trees in any condition standing within reach of improvements or human use areas represent hazards
that could lead to damage or injury.
Please call if you have any questions or if we can be of further assistance.
Sincerely,
Bob Layton ISA Certified Arborist #PN-2714A Tree Risk Assessment Qualified (TRAQ)
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Subject Trees #1 and #2 on right
Tree #1 – forked trunk, sound attachments to trunk
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Tree #2 – forked trunk. Weaker ‘V’ – shaped attachment to trunk
Grouping of trees to be removed for building addition
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Neighboring cottonwood trees east of building
Neighboring cottonwood, poor stem taper, ivy infestations
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ROW Sweetgum trees
Weak forked attachment on Tree #103
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Root from Tree #105 lifting sidewalk
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Neighboring tree #106, looking north from subject property
Neighboring tree #107, looking north from subject property
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Neighboring tree #9, looking west down north property line
Tree Summary Table American Forest Management, Inc.
For:4512 Talbot Road S Date:12/3/18
Renton Inspector:Layton
Tree/Tag #Species DBH Height Drip-Line/Limits of Disturbance (feet)Condition Comments Proposal
N S E W
1 Austrian pine 18 45 12/10 14 12 14 Good trunk forks at 7', good attachment save
2 Austrian pine 21 51 12/10 12 13 14 Fair trunk forks at 12', weak attachment save
3 Deodar cedar 16 71 18/10 10 8/8 16 Good on west edge of grouping remove
4 Deodar cedar 19 70 NA NA NA NA Good many exposed large surface roots remove
5 Deodar cedar 11 62 NA NA NA NA Good remove
6 Deodar cedar 16 68 NA NA NA NA Good many exposed large surface roots remove
7 Austrian pine 22 64 NA NA NA NA Good remove
8 Austrian pine 20 57 NA NA NA NA Good minor crook remove
101 sweetgum 13 43 12 6 8/10 12 Fair heavy lean northwest, rope around trunk TBD
102 sweetgum 15 45 16 14 14/10 16 Good typical form TBD
103 sweetgum 15 46 12 12 12/10 14 Fair forked top, some decay at fork, old failure point TBD
104 sweetgum 17 54 10 14 10/10 12 Good forked top, fair attachment TBD
105 sweetgum 19 52 18 14 16/12 14 Fair forked top, weak attachment TBD
106 red maple 18 30 NA 17/13 NA NA Fair forked trunk at 6', weak attachment, 15' to curb line Protect
107 Western red cedar 19,20 48 NA 14 NA NA Fair 13' to curb line, two main stems Protect
9 Western red cedar 22 47 NA 12 13 12 Good 10' to building Protect
Drip-Line and Limits of Disturbance measurements from face of trunk
ROW/Neighboring Trees