Mountain pine beetles in post-burn lodgepole pine forests

Crisia Tabacaru1 Jane Park2, Nadir Erbilgin1

1University of Alberta, 2Parks Canada

Acknowledgements

Foothills Research Institute: esp. Don Podlubny

Alberta Parks: esp. Rod Gow, Deb Milhousen, Melanie Percy, Joyce Gould Alberta Sustainable Resource Development: esp. Brad Jones, Seena Handel Parks Canada: esp. Erin Shepherd, James Cook

Canadian Forest Service: esp. Brad Hawkes Many amazing assistants and volunteers!

Management Options

Logging/Fire:

• cut and burn affected trees

• cut or burn unaffected trees to create boundaries

• cut or burn unaffected trees to heterogenize the landscape

© Brad Hawkes

BUT…

fire leaves live, partially burned trees

Conflicting results…

Elkin and Reid (2004):

MPB do NOT prefer burned trees

Powell et al. (2011):

MPB DO prefer burned trees

Healthy Burned ?

Main Objective

To determine whether burned lodgepole pine stands become sinks or sources for MPB populations in Alberta…

Study Sites

Saskatchewan Crossing

Ya Ha Tinda Ranch

Mt. Nestor

Methods

15 plots (10x10m) per fire injury class X 3

classes X 3 sites = 135 plots

Fire injury indices

1. Bole char (%)

2. Bole char height (m)

3. Ground char (%)

MPB colonization—Mt. Nestor

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

2009 2010 2011

Pro

po

rtio

n o

f Tr

ees

Co

lon

ized

Low

Moderate

Unburned

MPB colonization—Mt. Nestor

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

2009 2010 2011

Pro

po

rtio

n o

f Tr

ees

Co

lon

ized

Low

Moderate

Unburned

MPB colonization—Mt. Nestor

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

2009 2010 2011

Pro

po

rtio

n o

f Tr

ees

Co

lon

ized

Low

Moderate

Unburned

2009 2010 2011

Bole char

Bole char height

Duff char

Individual fire-injury predicts MPB colonization

An example: bole char

2009 (year of fire) 2010 (1 year post-fire)

Pro

bab

ility

of

MP

B C

olo

niz

atio

n

Bole Char (%)

P = 0.043 P = 0.028

Bole Char not significant in

2011!

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

2009 2010 2011

Pro

po

rtio

n o

f Tr

ees

Co

lon

ized

Low

Moderate

Unburned

1. Why do MPB colonize burned trees more often?

2. Why is the MPB “population” decreasing in

the burned area?

Why do MPB attack burned trees more often?

Reproduction?

MPB Reproduction

0

5

10

15

20

25

30

35

Unburned Low Moderate

Mat

ern

al G

alle

ry L

engt

h (

cm)

a a

b

Nitrogen? Defensive chemicals?

Why is the MPB “population” decreasing in the burned area?

http://diptera.info/forum/viewthread.php?thread_id=18523&pid=83798;http://www.biolib.cz/en/image/id24102/;http://www4.agr.gc.ca/AAFCAAC/display;afficher.do?id=1266016811893&lang=eng;http://bugguide.net/node/view/247151;http://amberbam.com/omeka/items/show/15;http://www.flickriver.com/photos/ngompel/tags/automontage/

Subcortical Community?

Trapping

• Passive flight intercept traps

• Emergence traps

• Landing rate traps

Rearing What is emerging from logs in the three fire injury

classes?

MPB competitors (sub-family Scolytinae)

0

5

10

15

20

25

30

Unburned Low Moderate

Nu

mb

er o

f b

ark

bee

tles

2010

2011

a a

a

a

b

b

MPB competitors (sub-family Scolytinae)

0

5

10

15

20

25

30

Unburned Low Moderate

Nu

mb

er o

f b

ark

bee

tles

2010

2011

a a

a

a

b

b

Management Implications

Questions?