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Event Details

Advanced Tree Risk Assessment: Principles and Practice

Date: July 17, 2017
Location: University of Washington CUH Douglas Class Room, Seattle, WA, UNITED STATES
Organizer: Pacific Northwest Chapter of ISA
Sponsor: Pacific Northwest Chapter of ISA
Description: Tree risk assessment is an area of urban forest management that has evolved rapidly in the past decade. We have moved from simple hazard tree assessment concepts into a more sophisticated understanding of risk in general. With the introduction of the ISA’s Best Management Practices document for Tree Risk Assessment, and the Tree Risk Assessment Qualification (TRAQ), several new approaches and guidelines have been introduced. Within the field of tree risk assessment there are many techniques and concepts to master; from basic principles through to sophisticated diagnostic techniques.

This course will focus on Level Three advanced tree risk assessment, but will also link this to Levels One and Two to show when Level Three may be required, and how to relate it to other work.

This course will be delivered by Dr. Julian Dunster, the designer of the original Certified Tree Risk Assessor credential (TRACE) and author of the new ISA Tree Risk Assessment manual for the TRAQ course. The course will be of interest to anyone practicing tree risk assessment, and especially arborists already holding the TreeRisk Assessment Qualification.


Dr. Julian Dunster has unique academic and professional qualifications. He is a Registered Consulting Arborist, a Registered Professional Forester, and a Registered Professional Planner, and in addition to two degrees in forestry, he holds a Doctorate in Regional Planning and Resource Development. Julian has over thirty years of hands on experience from assignments all over the world, and his innovative work has been recognised with many awards. Julian uses these qualifications and expertise to provide you with practical, science based information, combined with a pragmatic understanding of what will or will not work well.


9:00 to 10:00 Introduction
10:00 to 10:15 Break
10:15 to 11:15 Biomechanics Part 1
11:15 to 12:15 Biomechanics Part 2
12:15 to 12:45 Lunch
12:45 to 1:45 Testing Protocols
1:45 to 2:00 Break
2:0 to 3:00 Typical Tests
3:00 to 4:00 From Theory to Practice

Levels of Assessment

Review how each level feeds into the next one to provide increasing levels of detail.

The Implications of Advanced Assessment: An Overview

why do you need it?
asking the right questions
knowing what to look for
knowing what you are looking at
professional and legal implications
Knowing What to Look For

baselines: the biological and mechanically ‘perfect’ tree
variations around ‘perfection’ and what they might mean
Knowing what you are looking at
Body Language: how to read and interpret it
Theorising ideas about what any one variation might mean
How to test your theory and see if you are right
Testing Techniques

Invasive versus non-invasive issues
core sampling
Micro resistance drilling
sonic tomography
Interpreting the results, and relating these back to the risk assessment
Documenting and Defending the Results

The importance of clearly documenting the thought processes that lead you to undertake a Level Three assessment. Showing where, why and how you tested, and what you concluded based on the results.

Class Session Discussing Real World Examples

Participants are encouraged to submit beforehand a brief outline of a case study about investigations or anomalies they have encountered (details will be provided with the registration information). Up to six of these will be selected for presentation and discussion in class. We will examine the basic issues and then decide what we would have done, and how we might have interpreted the issues to arrive at a conclusion.

Hands-on Session

Following the class discussion participants will have an opportunity to try out various techniques including increment coring, cordless drills, Resistograph®, and sonic tomography equipment. This will be an indoors session using samples of wood, or outdoors if the site and weather permit.

Refund Policy

Cancellations made at l
Contact Name: Dana Hatley
Contact Phone: 8003354391
Contact FAX: 5038741509
Contact Email:

Seats Available: 25
CEUs available: Yes

Start Date: 9:00 AM, July 17, 2017
End Date: 4:00 PM, July 17, 2017

Address: University of Washington CUH Douglas Class Room
3501 NE 41st Street

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