390 Garden Lane Arborist Letter
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Arbor Report
Feb. 21, 2022
Nancy Russell
Nb.russell7@gmail.com
(757)839-1718
Summary: I assessed the risk of 2 oak trees and 2 hickory trees on your
property. With a level 2 assessment, I found trees are within fall distance of
home. I gave your trees a POSSIBLE risk rating due to fall distance and lean
towards home. Consequences of failure would be severe, due to tree being
within fall distance of home. This letter is in reference to Florida statue 163.045.
Scope:
Re: Tree Health and Risk Assessment for 2 water oak trees and 2 hickory trees on your property
at address 390 Garden Ln. Atlantic Beach, Fl. 32233
Assignment:
Services were retained to assess the current health and risk of 2 water oak trees (Quercus lafloria).
2 hickory trees and provide recommendations and a professional opinion on the risk the trees may
pose. The risk assessment for these trees is based on the proximity of the tree to the home.
Time Frame: Within 2 years
Methodology:
This tree was visually inspected using a Level 2, Tree Risk Assessment as defined by the
International Society of Arboriculture (ISA). This level of inspection includes a 360-degree
visual evaluation of the tree from top to bottom including a review of the crown, trunk, root flare,
and above-ground roots. Risk and liability determinations include location to building structures,
public rights-of-ways, streets, sidewalks and nearby utilities. These trees were verified to size
using standard Diameter at Breast Height (DBH) and was also inspected for evidence of defects
that would cause the tree to be a risk to any of the assets identified during the site anaylisis.
The Level 2 Inspection is used to help determine three main categories of risk; Likelihood of
Failure (Imminent, Probable, Possible and Improbable), Likelihood of Impact (High, Medium,
Low, Very Low), and Consequences of Failure (Severe, Significant, Minor, Negligible).
Together, these three risk categories can be used to help the property owners in making decisions
for pruning, mitigation options, and / or removal.
(Figure 1. Satellite Image of Property)
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Observations:
The tree: The 2 water oak have a DBH of 14”, 18” approximately 30’ to 40’ in height. The
hickory trees have a DBH of 25’ and 30” and are approximately 40’ to 45’ in height.
Tree health: Normal
Defects & Condition of concern: With in fall distance of home.
Photo documentation:
(Optional)
Analysis: (Give analysis of tree)(Optional)
Primary concern: The trees inspected were given a risk rating in relation to the targets that are
within the drip line of the tree, and the occupancy rate of the target. The trees risk rating is as
follows.
Additional concerns:
Risk Ratings Explained: POSSIBLE
What does POSSIBLE RISK for the home mean? Risk ratings are comprised of three parts. My
assessment determined that within the 2-year time frame:
1. The likelihood of failure is possible.
2. The likelihood of striking an asset (home) is
High.
3. The consequences (damage) of this event would be significant (considerable damage
would be done to the house)
What does MEDIUM RISK posed by large dead branches for people mean? Risk ratings are
comprised of three parts. My assessment determined that within the 2- year time frame:
1. The likelihood of failure is possible..
2. The likelihood of striking an assets (people) high.
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3. The consequences (damage) of this event would be severe.
Mitigation options:
There are several options that can be considered for mitigation to lower your risk from this tree.
1. Pruning to reduce the length of 10 of the highest branches by 30%. Unfortunately,
the branching nature of live oak trees makes reduction pruning difficult. Many
heading cuts may be necessary to get the 30% length reduction. The heading cuts
will lead to internal branch decay that will need to monitor and mitigated over time.
With this treatment the residual risk would become LOW RISK
2. Do nothing and continue to monitor the tree with regular inspections.
3. Remove the tree to mitigate all residual risk to assets.
Residual risk:
With option (1) there is a low residual risk, choosing option two will keep the tree risk rating at
medium for whole tree failure. Option three will remove all residual risk.
Reinspection:
This tree should be re-inspected every (time frame) unless you have additional health or safety
concerns that warrant more frequent attention. Tree inspection services should be performed by
and ISA Tree Risk Assessment Qualified (TRAQ) arborist skilled in the science of tree risk
assessment. I can perform these services should you desire.
Assumptions & Limiting conditions:
My inspection was a ground based visual inspection that also included internal drilling to detect
decay. The inspection was limited to defects that can be seen while standing on the ground.
There may be defects below ground or in the canopy that were not visible from
this perspective. These hidden defects may result in the failure of branches, trunks, or roots. No
other trees on this property were inspected other than those specifically addressed in this report.
GLOSSARY
Normal Weather. This tree risk assessment is based on ‘normal weather’ for the region.
Hurricanes are considered ‘abnormally extreme’ weather and were not considered in this risk
assessment. Any tree can fail during abnormally extreme weather.
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Response growth. Response growth is wood formation that compensates for weaknesses caused
by defects that naturally occur in trees, like hollowness.
Level 2 Tree Risk Assessment. A level 2 Tree Risk Assessment is a basic assessment providing
a detailed visual inspection of a tree and surrounding site that may include the use of simple
tools. It requires that the tree risk assessor inspect completely around the trunk looking at the
visible aboveground roots, trunk, branches, and site.
ISA Tree Risk Assessment Methodology – the categorization of tree risk based on the ISA’s
Best Management Practices categorization of likelihood of tree failure, the likelihood of
impacting a defined asset, and the likely consequences of the failure and impact. The four
categories of tree risk are low, moderate, high and extreme.
Level 3 Tree Risk Assessment. A level 3 Tree Risk Assessment is an advanced assessment
performed to provide detailed information about specific tree parts, defects, assets, or site
conditions. Specialized equipment, data collection and analysis, and/or expertise are usually
required.
DBH. DBH stands for Diameter at Breast Height and it is the diameter of the tree measured at
4.5 feet above the ground.
Decay Formula. The tree risk decay formula is based on ‘mechanical pipe formula’ and is a
ratio of stem wall thickness to diameter. The physical loss of more than two-thirds of the trunk
makes the tree likely to fail during normal weather. The ‘decay formula’ assumes a centered
symmetrical decay pattern and a tree with a balanced canopy. The decay formula is a starting
point and many other factors must be weighed that increase or decrease likelihood of failure.
Residual Risk. Residual risk is the risk rating after a mitigation action is completed.
Risk Ratings Range. The range of possible risk ratings is low, moderate, high, and extreme.
Normal Weather
Weather common in this area, storms that typically occur every year. Normal weather for
Southwest Florida is defined as a thunderstorm that produces 50 to 55 mph wind gusts and heavy
rain.
Heading cuts. A pruning cut that removes a branch or stem between nodes leaving a stub.
Time Frame. Time frame is the duration of time for the assessment.
Thank you, Robert Sackett
ISA Certified Arborist Fl-9350A
Tree Risk Assessment Qualified
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My inspection was limited to above-ground observations of the subject tree and the surrounding site. My inspection
was based solely upon my site evaluation and any information provided to me. All of the information provided to
me regarding the history of the site and the tree was assumed to be true. If any information is found to be false, the
conclusions in this report may be invalidated.
This report is a risk assessment. However, this report is not intended to be legal advice. I do not guarantee the safety,
health, or condition of the subject tree. There is no warranty or guarantee, expressed or implied, that problems or
deficiencies in the subject trees may not arise in the future.
Arborists are tree specialists who use their knowledge, education, training, and experience to examine trees,
recommend measures to enhance the beauty and health of trees, and attempt to reduce the risk of living trees. Clients
may choose to accept or disregard the recommendations of the arborist, or to seek additional advice.
Arborists cannot detect every condition that could possibly lead to structural failure of a tree. Trees are living
organisms that fail in ways we do not fully understand. Conditi ons are often hidden within trees and below ground.
Arborists cannot guarantee that a tree will be healthy or safe under all circumstances, or for a specified period of
time. Likewise, remedial treatments cannot be guaranteed.
Trees can be managed, but they cannot be controlled. To live near trees is to accept some degree of risk. The only
way to eliminate all risk associated with trees is to eliminate all trees.