Abating Tree Failure Along State Roads and Highways

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2 Abating Tree Failure Along State Roads and Highways

3 Louisiana Transportation Conference 2009 Abating Tree Failure Along State Highways and Roads by Malcolm M. Guidry Consulting Arborist Covington, LA February 10, 2009

4 Abating Tree Failure

5 Abating Tree Failure Along State Roads and Highways Trees are the dominate element of the landscape along our roads and highways Objective Protect people and property from harm by mitigating structurally defective trees that pose a risk for failure

6 Wind Throw

7 Highway

8 Highway

9 Structural Defect

10 Tree a Living Organism Grow old and change over time Environmental extremes storm wind forces lightning flooding drought stresses

11 Tree a Living Organism Stand ground or perish Against All forces of nature

12 To Survive a Tree Must Stand Its Ground or Perish

13 Live Old and Rotten

14 Adapt or die Tree a Living Organism Environmental Stresses Physical non-living Biological living

15 Tree a Living Organism Environmental Stresses Storms Lightning Fire Flooding Construction Standing Water Site Constraints

16 Invasive Acts by Man Construction

17 Construction

18 Environmental Extremes storm wind forces lightning flooding drought stresses

19 Storm Force Wind

20 Storm Force Wind

21 Storm Force Wind

22 Wind Loading

23 Environmental Stresses Biological Insects Rot Fungi Diseases

24 Insect Southern Pine Beetle

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26 Disease

27 Tree Defects Tip die back Hanging limbs Dying/dead trees Trunk cankers V crotch trunks Root problems Dead/dying limbs Open rot cavities Wood rot Cracks along trunk Poor architecture Leaning trees

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29 Die Back of Outer Branches Dead/Dying Limbs

30 Open Rot Cavities

31 Open Rot Cavities

32 Dying Roots/Dying Trees

33 Wood Rot

34 Cracks Along Trunk Obvious

35

36 V Crotch Trunks

37 V Crotch Trunk

38 V Crotch Trunk

39 V Crotch Trunk

40 Poor Architecture

41 Root Problems

42 Defects Obvious and Hidden Failure can be predicted Knowledge/experience

43 ISA Arborist News

44 Tree Risk Assessment Article

45 Tree Risk Assessment Article

46 Systematic Approach Assessing and managing trees which pose risk of failure: Inspecting Assessing Monitoring Scheduling Documenting Identifying Prioritizing Coordinating Executing

47 Abating Tree Failure Proactive vs. Reactive Crisis management Risk management Acceptable levels of risk

48 Heads-up Strategy Negligence is not an option regarding responsibility to remove potentially hazardous trees Ignorance and negligence is not a reasonable defense should people and/or property be harmed

49 Heads-up Strategy Best defense against negligence is to have a written systematic plan outlining a protocol or plan of action that protects the public from trees which pose obvious risk of failure

50 Body Language of Trees Symptoms/Problems: Loss of leaf color Reduced leaf density Tip dieback Dropping of branches Mushrooms Wood rot Rodents living in trees Black ants Reduced size of leaves Premature leaf drop Dying limbs Rotted branch stubs Trunk crevice Cavities Termites

51 Abating Defective Trees City of Mandeville Tree Management Model BMP Suggested ideas Nine Step Process as follows:

52 1. Inspecting Visual tree assessment: Windshield Walk through Individual tree inspection

53 1. Inspecting

54 2. Identifying Problems Considerations : Size Site Health Defects Species Location Structural integrity

55 Tree in Decline

56 ISA Tree Hazard Evaluation Form Tree characteristics Tree health Site conditions Target Tree defects Hazard rating Hazard abatement

57 3. Inventory

58 Inventory

59 4. Assessing Professional judgment : Health and structural integrity are not the same

60 4. Assessing Professional judgment : Green healthy trees may be structurally compromised Structurally defective tree can be healthy

61 4. Assessing Assessing need for action: Immediate High risk Moderate risk Low risk monitor

62 5. Prioritizing Prudent judgment: Manage risk knowledge and experience Hazard rating- low to high Failure potential- immediate action/asap/monitor Target- people and property

63 6. Monitoring Prescribed/Scheduled: Ongoing effort to inspect and reinspect to determine appropriate action as conditions change Agents of Change: Storms/ wind loading Site conditions Passage of time Insects/disease Stress/decline/death Old age

64 7. Coordinating Communicating/Enforcing Coordinating people and resources to protect the community from harm

65 8. Scheduling Level of Priority: Immediate ASAP Monitor

66 9. Executing Removing/Abating Tree Problems: Special Skills Tools In-house Contracting professionals

67 10. Documenting Keeping Records A Necessity: Written Photo documentation

68 Increase knowledge and skills of employees: orientation training manual on- job training worker safety public safety work orders job description training sessions task protective gear documenting

69 Standards of Professional Practice: OSHA ANSI Industry Standards

70 American National Standards Institute

71 ISA Arborist Certification Study Guide

72 ISA Evaluation of Hazardous Trees

73 Historical Perspective of Tree Risk Management Knowing the reasons and conditions of how and why trees fail provide valuable insight for managing trees along our roads and highways. Must have a plan Must follow the plan

74 Tree Risk Management: Inspecting/assessing trees for potential to injure people and or property Trees range from low-to-high risk for failure Managing trees to zero risk Reasonable Possible Not possible

75 Manage trees to acceptable levels of risk Written policies Management practices A successful risk management program provides a systemic approach to implement corrective measures within reasonable time frame.

76 Hazard potential Structural defects Target Risk Management Mitigation Options Liability Negligence

77 Liability and Risk Act of God: Violence of nature No Interference by man

78 Liability and Risk Negligence Failure to use such care as a reasonable prudent person would use under similar circumstances

79 Prudence Carefulness, precaution, attentiveness, good judgment as applied to action or conduct

80 Liability and Risk Reasonable Care Degree of care which a person of ordinary prudence would exercise in the same or similar circumstances.

81 Duty Legal obligation, breach of which can result in liability Periodically inspect trees Detect problems Employ appropriate action Abate problem

82 Liability and Risk Hazard tree Suggest immediate risk of failure

83 Abating Tree Failure Along State Roads and Highways Things happen Negligence is not an option

84 What you do / not do MATTERS