HomeMy WebLinkAboutTR_Grinsell Risk Assesment425-237-4141 | planterra.co | P.O. Box 226 Issaquah, WA 98027
TREE RISK
ASSESSMENT
Prepared for:
Jason Grinsell
999 Tacoma Ave NE
Renton, WA
Chris Welch
ISA Certified Arborist® #RM-1057
ISA Tree Risk Assessment Qualified
425-654-4745
TABLE OF CONTENTS
SUMMARY 3
METHODOLOGY 3
OBSERVATIONS 4
TREE #1 - WESTERN RED CEDAR (THUJA PLICATA) 4
RECOMMENDATION 4
SITE PLAN 5
PHOTOS 6
ASSUMPTIONS & LIMITING CONDITIONS 8
BASIC TREE RISK ASSESSMENT FORMS 9
SEE ATTTACHED 9
SUMMARY
On February 24, 2021 I evaluated a single western red cedar at 999 Tacoma Ave NE Renton,
WA. The purpose of the inspection was to perform a condition/risk assessment of the subject
tree and to make appropriate recommendations to reduce hazard risk where warranted.
The subject tree is within the striking distance of two homes and the neighboring church.
Occupancy rates of the target zone are constant and cannot be moved or mitigated.
Potential consequences of whole tree or partial failure could include extreme risk to people
and significant damage neighboring homes and fencing.
METHODOLOGY
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 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
damage, as well as if they have been injured, undermined or exposed, or if the
original grade has been altered.
Tree #DBH*Height Overall Risk Rating Recommendation
1 48"≈65'HIGH REMOVAL
*Diameter at breast height.
‣Inspection method included examining the tree with binoculars and sounding the
trunk with a mallet. No invasive methods were utilized unless described in the
sections below.
The subject trees were assessed under a TRAQ (Tree Risk Assessor Qualified) Level 2 Basic
Assessment (visual inspection from the ground).
OBSERVATIONS
Tree #1 - Western Red Cedar (Thuja plicata)
At 48” DBH this tree falls into the “Landmark Tree”
category as defined by the City of Renton. This tree has
a previous loss of top resulting in a co-dominant
situation with two remaining points of poorly attached
regrowth. The topping site is at about 40’ above the
ground. The regrowth is significant in size approximately
8-10 inch diameter stems, comprising 25% of the
canopy. The poor attachment of the co-dominant top is
the major risk factor for this tree.
Additionally a large cavity on the south side of the tree
at the base of the trunk extending into the root flare
approximately 20” wide and 16” deep is present.
RECOMMENDATION
It is my recommendation that this tree be removed. The present defects that cannot be
mitigated. This tree poses an elevated to high risk.
SITE PLAN
Subject Tree
PHOTOS
ASSUMPTIONS & LIMITING
CONDITIONS
1.Unless stated otherwise: Information contained in this report covers only those trees that
were examined and reflected the condition of those trees at the time of inspection; the
inspection is limited to a visual examination of the subject trees without dissection,
excavation, probing, or coring. There is no warranty or guarantee, expressed or implied that
problems or deficiencies of the subject tree might not arise in the future.
2.All trees possess the risk of failure. Trees can fail at any time, with or without visible defects,
and with or without applied stress.
3.Construction activities can significantly affect the condition of retained trees. All retained
trees should be inspected after construction is completed, and then checked regularly as part
of routine maintenance.
4.Sketches, drawings, and photographs in this report, being intended as visual aids, are not
necessarily to scale and should not be construed as engineering or architectural report of
surveys unless expressed otherwise.
5.The consultant/appraiser shall not be required to give testimony or to attend court because
of this report unless subsequent contractual arrangements are made.
6.Loss or alteration of any part of the consultant’s report invalidates the entire report.
7.Unless required by law otherwise, possession of this report or a copy thereof does not imply
a 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.
8.The consultant’s report and any values/opinions expressed herein represent the views of the
consultant/appraiser. The consultant’s/appraiser’s fee is in no way contingent upon the
reporting of a specified value, a stipulated result, the occurrence of a subsequent event, nor
upon any finding to be reported.
9.Ownership and use of consultant’s documents, work product and deliverables shall pass to
the Client only when ALL fees have been paid.
BASIC TREE RISK ASSESSMENT FORMS
SEE ATTTACHED
3/10/21, 11:05 AM
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SpreadHeightDBH
Target #1:
Practical to move target?
Restriction practical?Target Zone:
Target Protection:
Name Site Address City State Zipcode
Jason Grinsell 999 Tacoma Ave NE Renton Wa 98056
Tree #
1
Tools Used
Binoculars, Camera, Diameter Tape, Hipsometer, Sounding Mallet, Trowel
2/24/2021 10:10amAssessment Date:
48.00 65 40
Neighboring Residence, Primary Residence, None
Target within 1x height.
Constant No
No
Occupancy Rate:
Target #2:
Target Protection:
Target Zone:Restriction practical?
Practical to move target?Occupancy Rate:
Target #3:
Target Protection:
Target Zone:
Occupancy Rate:
Restriction practical?
Practical to move target?
Site Factors
History of Failures
Changed soil hydrology
Root cuts
Site Changes
FlatTopography Slope Aspect
Soil Conditions
Construction of church 2 years ago grading in root zone.
Prevailing Wind Direction SW S
Common Weather
Strong Winds Heavy Rain
Standard weather for east Puget Sound
lowlands.
Target within dripline
None
Constant No
No
Church
Tree Health & Species Profile
Failure Profile
Chris Welch
ISA Certified Arborist® #RM-1057ISA Tree Risk Assessment Qualified(425) 654-4745 chris@planterra.co
37.4°F and Partly CloudyWind: 3.107 mph (210°)Air Quality: Good (37)Visibility: 9.998 mi Barometric Pressure: 30.59 inHgHumidity: 83%
Weather Conditions
47.4993951, -122.1648671
Assessor Botanical Name Common Name
Thuja plicata Western Red Cedar
Normal
None visible
None visible
ft.ft.in.
Vigor Foliage
100%Normal
Chlorotic
Necrotic
Pests/Biotic
Abiotic
Description
Thuja plicata is among the most widespread trees in the Pacific Northwest. The tree is shade-tolerant and able to reproduce under dense shade. Thuja plicata is a large to very large tree, ranging up to 50-70 (200) ft tall
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Load Factors
Wind Exposure Protected
Medium
Normal
Normal
None
Some indications of construction activity in
root zone from construction of neighboring
building.
Relative Crown Size
Crown Density
Interior Branches
Vines
Recent or expected change in load factors.
10%Pavement over roots:
Basic Tree Risk Assessment
Backyard
3/10/21, 11:07 AM
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Sapwood Damage/Decay
Canker/Galls/Burls
Dead/Missing Bark
Cavity/Nest Hole
# Broken/Hangers
1Tree #
Page 2 of 4
Crown and Branches
Unbalanced Crown Live Crown Ratio:
Dead twigs/branches
Max dia. in inches:
Over-extended Branches
85%
0.0
Crown cleaned Flush cuts
Pruning History
Selected branch removal on church side,
likely for construction clearance.
Cracks
Lightning Damage
Three large scaffold branches
growing upward. In addition to
the scaffold branches, there is a
codominat top situation, poorly
attached new growth included
bark. Inspected from the ground
with binoculars.
Codominant Branches
Weak Attachments
In addition to the scaffold branches, there is
a codominat top situation, poorly attached
new growth included bark. Inspected from
A few minor branch failures.
Previous Branch Failures
Similar Branches Present?
Conks Heartwood Decay
Response Growth
Botanical Name Common Name
Thuja plicata Western Red Cedar
Jason Grinsell
Included Bark
Major concern is the co-dominate top with included bark. Fall distance of the
affected part is 40' feet and would make a significant impact.
Conditions of Concern
8-10" diameterPart Size
Fall Distance in Feet 40
Load on Defect Moderate
Likelihood of Failure Probable
5%
1.0Max dia. in inches:
Targets Potentially Impacted
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% of trunk circumference
missing wood:
Sapwood Damage/Decay
Canker/Galls/Burls
Cavity/Nest Hole
1Tree #
Page 3 of 4
Trunk
Dead/ Missing bark
Cracks
Sap ooze
Codominant Stems
Conks
Response Growth
Botanical Name Common Name
Thuja plicata Western Red Cedar
Jason Grinsell
Conditions of Concern Part Size:
Fall Distance in Feet:
Load on Defect
Likelihood of Failure
Some near cavity on trunk flare.
Abnormal bark texture/color
Included Bark?
No
Lightning Damage
Heartwood Decay
15%
16.00Depth of cavity in inches:
Poor Taper No
Lean °Corrected?
Limited regrowth.
Cavity 20” wide and 16 inches deep.
Whole tree
65
Moderate
Possible
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Name Notes
Depth: "
% tree’s circumference affected:
Conks/Mushrooms
Cavity
1Tree #
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Roots
Collar Buried/Not Visible
CracksCut/damaged roots
Response Growth
Botanical Name Common Name
Thuja plicata Western Red Cedar
Jason Grinsell
Conditions of Concern Part Size:
Fall Distance in Feet:
Load on Defect
Likelihood of Failure
Stem girdling
Distance from trunk:
Depth: "
Ooze
Dead Decay
15-20'
Surface roots affected, possibly more from construction activity. No visible signs. Building foundation within the drip-line of the tree. Construction completed within the last two years.
None Witnessed
16.0
Cavity in trunk extends into root zone. On th side where construction occurred. Remainder of flare and roots on primary residence side are in good condition.
Root Plate Lifting
Soil Weakness
Root collar decay related to trunk cavity.
Whole tree
65
Minor
Possible