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City of Thunder Bay: Emerald Ash Borer Strategic Management Plan

November 2016

Thunder Bay’s Beautiful, Vibrant Urban Forest

• Living asset

that is an

important part

of our lifestyle,

economy and

governance

• Makes

Thunder Bay

more walkable,

beautiful,

healthier, and

resilient

Tree asset under threat: aging, shortage of maintenance,

changing climate, invasive pests, etc.

A sustainable urban forest is a goal that

underpins numerous Corporate plans

• Discovered in 2002 in Windsor/Detroit

• Arrived in wood packing materials on ships

• Has travelled across 25 American states and 2 Canadian provinces- human movement (eg. Firewood)

• Killed millions of ash trees and is predicted to cost 10’s of billions of $ in Canada and US

Emerald Ash Borer

EAB Detection: Signs & Symptoms

Defoliation

Sprouts Bark Cracking

EAB larvae • Not evident until 3

years or more after

becoming infested

• Larval

stage

does

damage

EAB Detection

Prism traps and lures Early Detection

Branch Sampling

• All species of ash (Fraxinus sp.)

Proactive Planning for EAB

in Thunder Bay

– Nearly 25% of our street trees are ash

– Became informed about EAB

– Build awareness internally, with stakeholders and with public

Preparing For EAB Arrival

Ottawa- Example of impact over 3 years

• Stormwater Management

• Energy Savings – heating and cooling

• Property Values

• Health/Social Benefits

• Aesthetic Appeal

Loss of

Tree Cover =

Loss of Services

to Community

Natural Stands of Ash

Specialty Wood Products

First Nations Traditional Trades

Black ash

• New insect to North America

• Huge economic, social, environmental, and cultural losses

• All ash trees die & become hazardous quickly (2 years)

• No Zero-Cost option

• All ash trees die unless preventative treatment is given

What has been learned?

– Evolved from workshop in 2010

– Comprised of public, private, non-profit sectors

– Goal was to provide a coordinated regional response to prevent spread of EAB or, if introduced, slow it down.

– Advertised “Don’t Move Firewood”

message across NWO

– 29 signs installed across NWO

EAB Task Force – Northwestern Ontario (2011)

EAB Awareness Ribbon Campaign

Before EAB’s

arrival: visualize

the impact of the

pest

Installed by: CFIA, MNRF, City of Thunder Bay, Regional Partners

Monitoring for EAB

Year Thunder Bay Region

2010 10 10

2011 27 27

2012 27 13

2013 27 13

2014 70 30

2015 60 73

2016 126 86

Proactive preparation

Trapping doubled once EAB found

Updated Street-Tree Inventory

(2015)

All Street Trees (30,000) Ash Street Trees (6,300)

Street Trees

• Top 3 species

– 22% are ash

– 20% are maple

– 8% are linden

Annual Value of Thunder Bay’s Boulevard Ash Trees

Stormwater Management

$173,625

Added Property Value

$203,052

Electricity Reduction

$73,822

Natural Gas

Reduction

$134,818

Air Quality

Improvement

$34,488

CO2 Reduction

$24,748

$644,571 yearly Kotska, Katelyn. 2016. The Economic Benefits of Ash As Urban Street Trees in

Thunder Bay. Lakehead University Fac. Nat. Res. Mgt. Thesis. 115 pp.

Tree Benefits Accrue with Age

Approx. 30

years

before

large

benefits

from trees

Replacement

of large tree

with young=

reduction of

benefits

Trees are

only asset

to

appreciate

with age

EAB Strategic Management Plan

NO $0 COST OPTION

Includes all aspect of management

including removal, stumping, planting,

monitoring and surveying, wood disposal,

communications, project oversight

Management Options

4 management options presented to Council

• Passive /“Do nothing”, remove and replace trees as they die

• Active, treat 50% (or 30%) of eligible trees and remove and replace remaining as they become infested

• Proactive, treat 50% (or 30%) of eligible trees and remove and replace trees in advance of infestation

• Aggressive, manage all public and private trees with treatment or proactive removal and replacement. Not feasible due to lack of by-law and $

Management Options Management

Option

% Level of Chemical

Treatment for Candidate

trees

Cost

(million)

Passive $7.6

Active 30 $6.8

Active 50 $6.3

Proactive 30 $6.8

Proactive 50 $6.3

Aggressive Unknown, over $10

City Council

Approved

The cost of treating a trees over the course of an outbreak is almost always less than

the cost of removing, disposing, and replanting. This doesn’t take into consideration the

ecosystem services that are being provided.

TreeAzin Systemic Insecticide

Treatment

• Used in other municipalities • Injected under the bark • Applied every 2 years (+1) • Price: $4/cm diameter; 30cm tree=$150/2yr; $900/10yr

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5 6 7 8 9 10 11 12 13

EAB

Po

pu

lati

on

Years after EAB arrival

Success Depends on Application Timing

Early

93%

Late

40%

Treatment

started

early in

infestation

results in

much

greater

survival

rate of ash

trees

EAB Discovered in Thunder Bay-June 24, 2016

• Original find on corner of Fourth Ave and Memorial Ave • Now found in approximately 20 trees in 3 locations across the City

Fourth Ave

Goal:

Slow EAB population growth

and ash mortality

• We have treated 95 trees

within 500m of initial find

with grant funding

• We are removing ash

trees that have poor

structure and health

• We are identifying the

1700 which will be treated

• We are working within the

CFIA quarantine zone

• An expected new City limit

quarantine zone will be in

place early next year

Approved EAB Management Strategy • Now we develop an implementation plan

– Continue to monitor spread of the infestation

– Identify tree replacement options

– Identify trees to be injected/ protected

– Explore wood disposal and utilization options

– Investigate sources of funding

– Maintain and expand partnerships

– Continue to keep public informed

– Keep up to date with research

Ray Boulevard

www.thunderbay.ca/eab