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