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Event Details

Advanced Tree Appraisal: Anchoring Appraisals with Multiple Methods

Date: January 23, 2018
Location: Clackamas Community College, Oregon City, OR, UNITED STATES
Organizer: Pacific Northwest Chapter of ISA
Sponsor: Pacific Northwest Chapter of ISA
Description: Most appraisal training is focused on a very narrow slice of the world of tree appraisal: the Trunk Formula Method. This course explores the plethora of other methods that can be used by tree appraisers.

The course begins with an explanation of the concept of anchoring and how to evaluate the reliability, accuracy, and precision of data points. It then gives an overview of all three approaches to appraisal: cost, market, and income. It dives in and explores methods of appraising partial loss, diminution of market value, percentage contribution, and net present value. Next, participants have an opportunity to reconcile the many possible methods as they are applied to a given assignment.

The last third of the class is a series of case studies that give participants the opportunity to practice applying the methods discussed in class and to then choose and defend their own final appraisal conclusion.

Importance of anchor values
Credibility and relevance
Defining the assignment
Data collection

10:00-10:15am: 15-min BREAK

Trunk Formula Method
Partial losses
Cost of repair
Cost Forwarding
Discounted Cash Flow

12pm-12:30pm: LUNCH BREAK

12:30pm-1:30pm: MARKET AND INCOME

Direct sales comparison
Contributory real estate value
Direct income approach
Net present value

1:30-1:45pm: 15-min BREAK


4pm: CEUs sign-in


Terry Flanagan is a Board Certified Master Arborist as well as a Municipal Specialist and Tree Worker Specialist in Tree Climbing and Aerial Lift. He is also Tree Risk Assessment Qualified. Terry was one of the first to be BCMA certified and chaired the panel of experts that helped create the Tree Risk Assessment Qualification. He has been an instructor of the program since the beginning and serves as a mentor instructor for new instructors coming into the program. He also taught the Arboriculture class at Clackamas Community College for many years up until he assisted in creating a full degree program for Arboriculture at the college.

He is the principal at Teragan & Associates, Inc. created in 2000 offering consulting for every aspect of arboriculture including risk assessment, plant appraisal, tree development plans, plant and landscape management plans as well as diagnosis for plant decline.

He has served in many leadership roles for the local chapters and the International Society of Arboriculture (ISA) serving as its president in 2013/2014. He currently serves as the chair of the Tree Climbing Competition Series Committee (TCC SC) working to improve the Tree Climbing Series worldwide at the different levels of the competition.

James Komen is a Board Certified Master Arborist and Registered Consulting Arborist. He has been published in two academic journals, presented at the ASCA and ISA Annual Conferences, and taught and co-taught multi-day training courses on tree risk assessment and tree appraisal. High energy and excitement define his teaching philosophy. While concepts, terms, and definitions are clearly demarcated in class, he emphasizes not only getting the "right" answer, but providing adequate justification.

Refund & Cancellation Policy

Cancellations made at least 10 days prior to the event will be refunded at 100%.
Cancellations made within 5-9 days of the event will be refunded at 75%.
Cancellations made within 1-4 days of the event will be refunded at 50%.
Refunds will not be made available for no-shows.
Contact Name: Dana Hatley
Contact Phone: 8003354391
Contact FAX: 5038741509
Contact Email:

Seats Available: 45
CEUs available: Yes

Start Date: 9:00 AM, January 23, 2018
End Date: 4:00 PM, January 23, 2018

Address: Clackamas Community College
19600 Molalla Ave
Oregon City

©International Society of Arboriculture 2009-2018
PO Box 3129 • Champaign, IL 61826, USA • +1.217.355.9411

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