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Impact of Storms in the Northeast : Weather and Trees

Richard J. Hauer, Ph.D.College of Natural Resources

University of Wisconsin-Stevens Point

Storm Preparedness and Response:Lessons from the Past, Techniques and Tools for the Future

September 26, 2006 Providence, Rhode IslandSponsored by the Rhode Island DEM and the USDA Forest Service

The Not So Beauty of Storms

Safety CleanupRepair

Overtime

Storm Response … A Three Act Play

Act I: The Problem (Impact of Storms)

Act II: The Response (DPRR Cycle)

Act III: The Outcome (M & M)

http://www.uwsp.edu/cnr/faculty/hauer/index.htm

or Google Hauer UWSP

Bio …. Logical in the Urban Forest

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Predictable and Preventable Act One:Weather, Storms and the Urban Forest

• Types– Floods– Moisture Stress/Drought– Ice Storms– Tornadoes– Lightening– Hurricanes– Nor’easter– Straight-line Winds– Forest Fires

• When and how often?

Outcomes

Acute versus

Chronic

Short-term or Residual

Temperature

• Means and Extremes– Average High 82°– Average Low 20°– Highest Temp 104° (August 2, 1975)– Lowest Temp -25° (February 5, 1996)

• Hardiness and Heat Tolerance

Minnesota Tree Spade Planting January 10, 2003

Spruce Winter Desiccation, Planted the Previous Fall (Purplish Coloration) Frost Damage to Trees

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Moisture Stress and Drought• Moisture Stress:

– Plant response– Reduced growth and development

• Drought:– Meteorological definition– … period of abnormally dry weather sufficiently long

enough to cause a serious hydrologic imbalance in the affected area.

– … severity depends on the degree of moisture deficiency...duration... and to some extent the size of the area affected.

– … usually reserved for a time of moisture deficiency that is relatively extensive in time and space.

Species Response to Moisture Stress and/or Drought

Copyright © 2006, PRISM Group, Oregon State University, http://www.prismclimate.org Map created 09/21/2006.

Effects of Moisture Stress• Deficiency• Excess

• Physical damage– Snow– Ice– Fires

Hail

Direct and Indirect Effects of Hail

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Ice Storms

How Common

Ice Storm Development

1998 January Ice Storm inNE US andSE Canada

Flooding

Species and Duration

XSweetgumLiquidambar styracifluaXBlack walnutJuglans nigraXKentucky coffeetreeGymnocladus dioicus

XHoneylocustGleditsia triacanthosXWaterlocustGleditsia aquatica

XXgreen ashFraxinus pennsylvanicaXWhite ashFraxinus americana XHackberryCeltis occidentalis

XShagbark hickoryCarya ovata XBitternut hickoryCarya cordiformis

XWater hickoryCarya aquaticaXRiver birchBetula nigra XHazel alderAlnus rugosaXXSilver mapleAcer saccharinum

XRed mapleAcer rubrum XXBoxelderAcer negundo

Tolerant³Tolerant ²Tolerant¹NameSpecies

Intolerant4SomewhatVeryCommon

Some Flood Tolerance Ratings of Tree Species: Intolerant < 30 days, Intermediate 30 to 60 days, tolerant > 60 days

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What Caused This?Winds and Damage

• Sustained winds

• Gusts

• Damage Categories– Defects (decay, branch structure, roots)– Sound Trees (resistance to wind, force)

Fujita Scale

Trees debarked261–318incredibleF5

Forest trees uprooted and carried207–260devastatingF4

Most trees in forest uprooted158–206severeF3

Large trees broken or uprooted113–157significantF2

Trees broken or uprooted73–112moderateF1

Twigs/branches break, shallow rooted species uprooted

40–72lightF0

Tree Damage

Wind Speeds (mph)DamageCategory

Beaufort Wind Scale

64 - 7212Trees broken or uprooted55 - 6311

47 - 5410Twigs break39 - 469Whole trees in motion32 - 388Large branches in motion25 - 317Small trees in leaf begin to sway19 - 246Small branches in motion13 - 185Leaves & small twigs in constant motion8 - 124Leaves rustle4 - 73

1 - 32Calm0 - 11Outcome

Wind Speed

Beaufort Number

Spruce (not a palm) Tree

in Crookston, MNNor’easter

• Forces– Wind– Snow

• Tree Damage– Many trees were blown down – More latter killed from seawater blown inland

• Ice The Groundhog Day gale (1976)– Maximum sustained winds of 102 mph– Equal to a Category 2 hurricane (gusts to 116 mph)

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Tornados

• Top 5 states (mean # per year, 1950–2004): Texas (134), Oklahoma (58), Kansas (56), Florida (51), Nebraska (43)

States with lowest incidence of tornadoes (total number, 1950–2004): Alaska (2), Rhode Island (9), Hawaii (31), Vermont (37), Oregon (87)

March 29, 1999 St. Peter Storm

Recovery from St. Peter Tornado What are the Safety Issues

Why is Safety Important?

Opps

Act II

Storm Preparedness and Response

Richard J. Hauer, Ph.D.College of Natural Resources

University of Wisconsin-Stevens Point

Storm Preparedness and Response:Lessons from the Past, Techniques and Tools for the Future

September 26, 2006 Providence, Rhode IslandSponsored by the Rhode Island DEM and the USDA Forest Service

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Storm Damage Preparedness

Now is not the time to start planning!

Now is the time for recovery and returning order

An Integrated Approach

What we Know From Tree Risk

Management:

1) Divide the community into tree risk zones

2) Tree failure is often

predictable and preventable

Historical Lessons Learned

84% of storm-damaged trees had pre-existingdefects that could have been predicted andprevented.

The Disaster Cycle1) Mitigation: activities that

reduce the effects of disasters

2) Preparedness: planning a response prior to a disaster

3) Response: activities during a disaster to minimize hazards in effective, efficient, and equitable ways

4) Recovery: returning to normal following a disaster

Disaster Cycle: Mitigation

• Tree Selection and Placement

• Tree Establishment

• Tree Maintenance

• Regular Tree Risk Assessment

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Disaster Cycle: Preparedness

• Staff Liaison/POC: know ICS; trained to access tree damage

• Tree Emergency Response Plan: guide before and after storm (prevention, clean-up, regulations, salvage/repair, replanting, mobilization agreements for people and equipment)

• Plan Coordination: assign responsibility, avoid conflicts

• Update Plan: periodic evaluation (annually), contracts, contacts, and changes

• Provide Training: what to do, who does it, when to do it

Disaster Cycle: Response

• Locate and Consult Emergency Plans, Debris Removal Plan, and Contact Lists

• Identify Live Electric Wires (in, on, or under trees)

• Implement Response Phase Triage– Response I – Debris clearance– Response II – Debris removal and disposal

Disaster Cycle: Response:Phase I – Debris clearance

• Clear priority traffic lanes and culverts

• Push debris to the side

• Clear at least one lane ASAP

• Clear major walkways

Disaster Cycle: Response:Phase II Debris removal and disposal• Establish routes and methods for clearing tree debris.

(hopefully set up before the disaster; if not, try adopting routes used for trash pickup or snow removal)

• Use staging areas if needed (malls, playgrounds, etc.), then clear those after things calm down.

• Debris removal typically most difficult tree disaster problem for communities and individuals.

• In general, removal of debris from public property is eligible for FEMA assistance when a Federal Disaster has been declared and when it constitutes an immediate threat to life, public safety, or improved property.

Disaster Cycle: Response:Communication

• Basic Point: Communication is critical to surviving disasters. If you do not actively manage information during tree emergencies, things have a way of quickly getting out of hand and complicating your work.

• Set up: clear communication channels among emergency agencies and personnel.

• Establish and publicize: a phone number and staff person for public contact.

• Media: Work with the media early and often.

• Deliver: important messages to the community

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Disaster Cycle: Recovery

• Tree by Tree Assessment for Hazards

• Prioritize Repair (tree data, location, other)

• Update Tree Inventory

• Continue to Keep Records for Assistance– keep track of date, personnel, job, equipment, location,

and hours.– Consult FEMA forms and requirements

(http://www.fema.gov)

Survey of Immediate Threats

• Determine Priority 1 Removal (e.g., uprooted, split in half, undermined)

• Determine Priority 1 Pruning (e.g., >= 2”hanging, broken, or cracked)

• Targets (e.g., building, sidewalk, electric wire, road, or other important structure)

• Hire professionals• Standards (ANSI A300) • Verify before you pay

Storm Damage Assessment Protocol

FEMA Reporting & ReimbursementFEMA recommends communities have an Emergency Operation Plan

FEMA reimburses:

Debris removal costs (estimate of ft3 of debris)

Tree removal costs (50% crown loss)

Hazard reduction pruning (only hazard limbs)

Act III

Mitigation: Minimizing Risk and Damage

Richard J. Hauer, Ph.D.College of Natural Resources

University of Wisconsin-Stevens Point

Storm Preparedness and Response:Lessons from the Past, Techniques and Tools for the Future

September 26, 2006 Providence, Rhode IslandSponsored by the Rhode Island DEM and the USDA Forest Service

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Storm Damage PreventionStorm Damage Prevention

critical to public safety, similar in critical to public safety, similar in importance to other essential public importance to other essential public services such as:services such as:

Traffic light maintenance

Roadway construction & repair

Sewage disposal

Clean drinking water

Historical Lessons Learned

Storms will occur and the risk trees pose to the public safety are often very high.

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Post Storm Surveys in Minnesota

84 % of damaged trees had pre-existing defects that were preventable and predictable.

Most common pre-existing defects:Decay

Weak branch unions

Codominant leaders

Stem girdling roots

Historical Lessons Learned

84 % of storm-damaged trees had pre-existingdefects that could have been predicted andprevented.

Storm Failure Triangle

Tree Condition and Defects

Loading Event

Site Characteristics

Failure Potential

Risk Management

Urban Forest Management

PreventionPlantingMaintenanceRemovalEmergency ResponseAdministration

Assessment

Correction

Defect Defect CategoriesCategories

Prioritizing Prioritizing ““Levels of RiskLevels of Risk””

• Some need “immediate” attention

• Some placed on the “back burner”

• Some regarded as “acceptable,” e.g.,

Pot Holes

Uneven Sidewalks

Bridges

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A Systematic Approach is NecessaryA Systematic Approach is Necessary

To accurately assign levels of risk, managers need to be guided by a systematic approach:

•Observe

•Monitor

•Evaluate

•Prioritize

•Take Action

Predictable and Preventable

However, Many Potential Problems areHowever, Many Potential Problems are

Urban Forest Managers Must be Trained and Experienced in Risk Detection:

Levels of Risk Can be AssessedLevels of Risk Can be Assessed Monitor for Indicators:

• Decay

Monitor for Indicators:Monitor for Indicators:

• Poor Branch Attachments

Monitor for Indicators:Monitor for Indicators:

• Site condition changes, such as root loss

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Monitor for Indicators:Monitor for Indicators:

• Exposure to Wind Need Training and Experience toDetermine Best Treatment Options:

• Move the Target

• Treat the Tree

• Convert to Wildlife Tree

• Close the Site

• Remove the Tree

Urban Forest ManagersUrban Forest Managers

Treatment Options:

• Move the Target

Treatment Options:

• Treat the Tree

Treatment Options:

Convert to a “Wildlife Tree”[reduce the tree risk]

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Treatment Options:

Close the site[often not practical in urban settings]

Treatment Options:

• Remove the Tree

Design and Planning:• Minimize Utility Conflicts

Basal Pruning a

Hazardous Situation

Basal Pruning Gone Bad Design and Planning:

Provide adequate space

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Design and Planning:

Species to Site Selection

Design and Planning:

Minimize Construction Damage

Design and Planning

When Streets are Widened and Improved, Tree Spaces Shrink:

Damaging Factors with Street and Sidewalk Repair

Street Reconstruction on Tree Survival• Five Percent Greater Mortality, 1989 Study

• No difference 2005 Study, Why?

Figure 1. Condtion rating of street trees subjected to construction damage during street, curb, and sidewalk repair and undamaged control trees. (Bars are Std. Error of Mean)

76.774.4

71.871.0

0

10

20

30

40

50

60

70

80

90

100

1989 2005

Cond

ition

Rat

ing

(Per

cent

)

Control Damaged

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Design and Planning:

Create complimentarymaintenance practices

Sign Damage to Trees (Tree Kiosk)

The End!