René Alfaro, Brad Hawkes, Lara vanAkker

and Bill Riel Pacific Forestry Centre, Victoria, BC, Canada

Jodi Axelson Dept Geography, University of Victoria

Ian Cameron Azura Informetrics

Ecological impacts of the Mountain Pine

Beetle on the Foothills of Alberta

2

Contents

Introduction

Disturbances: drivers of ecosystem change

Need for establishing baselines

Need for forecasting growth and yield and

flow of ecosystem services following MPB

Work in the BC and Alberta

Forest transformation by MPB actual and

stand simulations

Knowledge gaps and opportunities

Conclusions

3

Ecology of lodgepole pine:

a fire regenerated species

4

Life after fire

5

The mountain pine beetle Forest management, climate change

Fire suppression and

selective harvesting for

species other than pine

during previous century,

created large forests of

pine

Beetle survival has

improved over much of

western Canada during

recent decades due to

global warming, allowing

populations to invade

areas formerly unsuitable

for MPB

6

Probable range of the MPB

A very plastic insect= High

potential for invasion

US Distribution from

McCambridge and Trostle 1970

Canada Distribution: from Alberta

and BC sources

7

Largest pine beetle outbreaks in BC and Alberta in recent history

Aerial surveys

begin

History of beetle outbreaks in BC

1980 1985 2011

BC Montana Border 31 years later

Ecological and timber impacts

9

The Cariboo-Chilcotin Plateau plots Established 1987, remeasured in 2001 and 2008

3 biogeoclimatic zones

Mixed-severity fire regime

Stands dominated by Pl

10

East Slopes sites

New range

Historic range

20 Years after MPB in Waterton National Park

12

Waterton Lakes NP, Red Rock Canyon

– 1982 and 2008

13

Methodology: Establishing beetle disturbance

baselines

Dating coarse woody debris

Dating regen. cohorts

Dating canopy layers

1. Past distribution of MPB outbreaks and return interval

2. Understanding impacts. Timber and ecosystem

Disturbance history in “even” and uneven aged stands

15

Results: Stand development after beetle

MPB is a natural thinning agent

Promotes increased growth among

the surviving trees

Allows for the establishment of

seedlings in understory

Creates coarse woody debris

History of the canopy layers of an “even-aged” lp stand Logan Lake, Kamloops

Axelson J., Alfaro, R., and Hawkes, B. 2009.

17

Beetle and stand dynamics: Bull Mtn. Study

Heath and Alfaro 1990 (re-surveyed in 2001)

Overstory Understory

Tree ring widths (mm)

1882-2001

Chilcotin: Growth release after 1970-80’s outbreak

19

Beetle

history of

in BC and Alberta

1630 1640 1790 1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

1630 1640 1790 1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

Sta

nd

MAN1MAN4MAN5WAT

MAN3MAN2OK14CASTMOY

OK15OK16

BLR10ST2BPARS

BLR11ST2CANG1ANG2

KATHCBAN08BLR09

K302KET2

KATHAKATHB

KET3KET1WHIT

CAN12CAN13

LAL3LAL2LAL1

CORRTUNKSAVOHALL

KOOTREV02CRAN

REV01BAN05CC163CC359CC103

GOLD03GOLD04

CC101CC102CC105CC106CC104CC120CC122CC121CC128CC125SASKXCC129CC130CC119CC116CC118CC107CC117CC124CC126

BULLCC108CC109CC115CC114CC110CC111CC113CC123CC112

JASPJWGDOIG

TWD2TWD3TWD9TWD6TWD7TWD8TWD5TWD4

PG

MAN1MAN4MAN5WATMAN3MAN2OK14CASTMOYOK15OK16BLR10ST2BPARSBLR11ST2CANG1ANG2KATHCBAN08BLR09K302KET2KATHAKATHBKET3KET1WHITCAN12CAN13LAL3LAL2LAL1CORRTUNKSAVOHALLKOOTREV02CRANREV01BAN05CC163CC359CC103GOLD03GOLD04CC101CC102CC105CC106CC104CC120CC122CC121CC128CC125SASKXCC129CC130CC119CC116CC118CC107CC117CC124CC126BULLCC108CC109CC115CC114CC110CC111CC113CC123CC112JASPJWGDOIGTWD2TWD3TWD9TWD6TWD7TWD8TWD5TWD4PG

1890’s 1930’s 1970’s

20

Bull Mountain 2001: A 320 year old tree: outbreaks every 52 years (40 years for entire BC)

Lodgepole pine growth

Year

Mea

n ra

dial

gro

wth

(mm

)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

1683

1700

1720

1740

1760

1780

1800

1820

1840

1860

1880

1900

1920

1940

1960

1980

2000

1970's1930's1860's1800's1760's

Douglas-fir

21

Beetle creates advance regeneration

22

From simple post-fire

stand structure…

Beetle and stand dynamics

To multiple cohort structure

23

Beetle creates coarse woody debris CWD from the 1970’s-80’s outbreak

24

CWD from the 1930’s

outbreak

Beetle creates coarse woody debris

25

Fire interactions Chilcotin

0

1

2

3

4

5

6

7

8

1564

1579

1594

1609

1624

1639

1654

1669

1684

1699

1714

1729

1744

1759

1774

1789

1804

1819

1834

1849

1864

1879

1894

1909

1924

1939

1954

1969

1984

1999

Year of scarring

Num

ber

of d

etec

ted

fire

scar

s (N

= 2

2)

1869 1906

1842

1776

Fire control

implemented

26

Brad plays with fire

27

Resiliency of the Chilcotin Forest after two

outbreaks

Density (stems/ha) Volume (m3/ha)

Layer Mean SE Mean SE

Overstory

(>7.0cm DBH) 413 84 27.9 5.3

Understory (<7.0cm DBH, taller than 1.5m)

1035 168

Regeneration (shorter than 1.5m) 4709 1429

Total 6157

Live pine in 2008 after 1970’s and 2000’s outbreak

Resiliency of the Chilcotin Forest after two

outbreaks

29

AC3R3T125

Initial conditions 2008

3 cohorts

30

AC3R3T150

2033

31

AC3R3T158PRE

2041 (immediately prior to light outbreak)

32

AC3R3T158

2041 Light outbreak removes 30 % BA

33

AC3R3T175

2058 New cohort is born

34

AC3R3T191PRE

2074 (immediately prior to outbreak)

35

AC3R3T191

2074 Massive outbreak kills 70% BA

36

AC3R3T200

2083

37

AC3R3T225

2108 New cohort is born

38

Results: Waterton National Park

Pine is mostly down

Forest dominated by

shade tolerant

39

History of beetle at Waterton

Stand 1

Stand 2

Stand 3

Stand 4

Stand 5

1880 1885 1890 1895 1900 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Outbreaks

1970’6-1980’s 1920’-1930’s

40

Overstorey Saplings Regeneration

41

Results: Waterton

Marked decline in lodgepole pine density

Increase in non-host species such as spruce and fir from 1981

to 2010

With the exception of stand 1, sapling and seedling densities

have increased in all stands from 2002 to 2010

High degree of variability in stocking between stands

Composition made up almost entirely of shade tolerant species

42

Conclusion: Stand dynamics cycle in BC

43

Conclusion: Stand dynamics cycle in Alberta

44

Conclusions

Stand-replacing fires initiate even-aged lp stands

Reduced fire in 20th century: MPB directs stand

dynamics

MPB transform stands into multiple age cohort

forests, initiated by repeated beetle thinning.

Or transition to other stand types

Long term impacts: alleviated by the presence of a

sub-canopy, and advance regeneration layers

which will form reasonably well stocked forests in

the future.

45

Impacts on timber and ecosystem services

Timber production is heavily impacted

Ecological impacts or ecosystem services:

If disturbance is part of cycle, business as usual

In novel habitats: transition to different

ecosystems

Caveat: climate change will alter natural

disturbance regimes.

46

“I’ll be back”

Dendroctonus ponderosanegger

http://cascadiascorecard.typepad.com/

48

Questions?