1. TNT – Targets and Trees Vince Urbina ISA Certified Arborist
ISA Qualified Tree Risk Assessor

2. Cooling pedestrians and businesses since 1962
Downtown Grand Junction
Cooling pedestrians and businesses since 1962

3. Cooling surfaces reduce heat island effect and prolongs life of asphalt

4. Trees create a comfortable and inviting environment

5. Tree $ Value City of Aspen
Tree Inventories – Overall Value of City-owned trees
1993 – $3,273,919
1996 – $4,145,572
2006 – $15,353,565
2017 – $15,984,049
The Tree Value Formula We Use:
ISA-RMC Tree Species Value X Basal Area X Species Factor X Condition Factor X Placement Factor = Tree Value

6. Largest Colorado Blue Spruce in City of Aspen Pioneer Park
Tree $ Value
Largest Colorado Blue Spruce in City of Aspen Pioneer Park
Diameter at breast height = 37 inches
Condition is Good
Placement is Good
Tree Value = $29,231

7. Tree $ Value Largest Tree on City of Aspen ROW Narrowleaf cottonwood
Diameter at breast height = 53 inches
Condition = Good
Placement = Good
Tree Value =$30,377

8. Right Tree - Right Spot - Right Reason
LESSON: Well-maintained tree planted in a good location will increase in value as it ages.
Right Tree - Right Spot - Right Reason

9. Tree Risk (def.) – the combination of the likelihood of an event and the severity of the potential consequences
Tree Hazard (def.) – tree part idenfied as a likely source of harm

10. Locate and Identify Targets
1. People – always the first and most important target to identify
2. Property (infrastructure) – targets that occupy the area that may be affected by a tree or tree part failure
3. Activities – annual events, festivals, gatherings, play areas
Targets (def.) – Are people, property, or activities that could be injured, damaged, or disrupted by a tree failure

11. Identify Target?
For me Children are extremely important targets
Children never look up and have no awareness of risk or danger

12. Identify Target?

13. Identify Target?

14. Identify Target?
What is the message to the public here?

15. Identify Target?
Where do people usually park?

16. Identify property?

17. Identify Property?

18. Identify Property?

19. Identify Property?

20. Identify Activity?

21. Identify Activity?

22. Identify Activity?

23. Identify Activity?

24. Identify Tree Parts That Could Impact a Target
Pay Attention to:
Dead trees or branches - You need to decide what branch size will define your acceptable or unacceptable level of risk.
Broken and hanging branches in the tree crown. AKA: hangers
Cracks in a branch, branch union or the main trunk

25. Dead Tree
Target?

26. Dead Branches
Target?

27. Deadwood

28. Previous Failures

29. Deadwood

30. Hanging Branches

31. Hanging Branches
Need a Target to be High Risk

32. Branch Crack

33. Trunk
Crack

34. Trunk
Crack
Owner Notified

35. Trunk Cracks

36. Other Tree Issues to Look Into
Lean
Codominant Trunk/Branches
Lack of Trunk Taper
Girdling Roots

37. Lean

38. Codominant Trunk

39. Girdling Root

40. How to Mitigate Risk Move the target (table, bench, artwork)
Restrict (fence off) access or reroute traffic
Prune out the problem tree part
Install structural support to limit or eliminate risk
Install a guying system or a prop to hold up branch
As a last resort, remove the tree

43. Bracing with Prop

44. Removal Should Be Your Last Option

46. Target?
Load on Tree Part and Strapping?

47. Where to go for Expert Help

48. International Society of Arboriculture
Organization that promotes the professional practice of arboriculture through research, technology and education.
There are more than 23,000 members throughout the world.
Many members hold credentials and qualifications that acknowledge a special skill like tree risk assessment.
These arborists understand the importance of their skill and are required to increase their expertise through continuing education.
To find a Qualified Tree Risk Assessor (TRAQ) near you go to arbor/findanarborist/findanarborist

51. American Society of Consulting Arborists
Organization of consulting arborists who are authoritative experts on trees.
Members are required to have extensive level of knowledge that ensures the safety, health and preservation of trees.
Some of the services provided by consulting arborists include: diagnosis of tree and landscape problems; expert witness and litigation; forensic investigation; tree risk assessment and surveys.
Many consulting arborists are also Qualified Tree Risk Assessors (TRAQ)
To find a consulting arborist that is a Qualified Tree Risk Assessor (TRAQ) near you, go to

54. Questions?
Vince Urbina