MONITORING MOUNTAIN PINE BEETLE LIFE CYCLE TIMING AND PHLOEM TEMPERATURES
AT MULTIPLE ELEVATIONS AND LATITUDES IN CALIFORNIA
Barbara
1
Bentz ,
1
Vandygriff ,
2
Coleman ,
3
Dunlap ,
Jim
Tom
Joan
Amanda
Camille Jensen5, Patricia Maloney6, Sheri Smith4
4
Garcia ,
1Rocky
Mountain Research Station, Logan, UT, 2Forest Health Protection, San Bernardino, CA, 3Eldorado National Forest,
4Forest Health Protection, Susanville, CA, 5Contract Specialist, Lake Tahoe, CA, 6University of Californian, Davis, CA
Lake Tahoe Basin NF - Lodgepole pine - 1782 m
180
Attacks
2009
3 Trees
250
100
80
60
40
Emergence
2010
20
200
Emergence
2010
5 Trees
150
2
t
Oc
27
2009
t
Oc
2
t
Oc
27
2009
2010
Date
180
160
Emergence
2010
100
120
100
Lassen NF 1635 m
30
3.0
Female
20
10
0
-10
-20
80
60
20
Methods
Oc
Oc
7
t2
2009
e 9 uly 4 ly 29 g 23 pt 17 ct 12 ov 6
n
J
N
O
Ju
Ju
Au
Se
Date
24
t7
13
19
p
y
e
g
l
e
n
S
Ju
Au
Ju
2010
Total Number MPB
October 20: instars I-IV
Date
2010
San Bernardino NF 2709 m
1.5
20
3.0
Male
10
0
-10
-20
50
Tahoe Basin NF 2932 m
30
Emergence
2010
60
40
2.5
2.0
1.5
20
10
0
La
-10
e
ss
a
ug
S
n
r
ah
eT
L
ak
-20
La
July 19
80
Oct 27
2009
Feb 4
Date
May 15
o
PP
L
e
k
a
eT
ho
eW
W
&
La
P
LP
k
ah
T
e
o
eW
BP
o
Iny
Sa
e
mb
Li
er
B
n
r
na
r
din
on
ny
i
oP
Aug 23
2010
Figure 4. Daily maximum and
minimum air temperatures at 3
MPB sites.
Figure 5. Size of adult MPB
that emerged in 2010 at
each site.
Attacks
2009
20
Summary
0
0
4
3
7
19
pt
e2
g1
ly
e
n
u
u
S
J
A
Ju
2009
t
Oc
2
t
Oc
27
4
9
6
3
2
7
9
ne July uly 2 ug 2 ept 1 ct 1 Nov
u
O
J
J
A
S
Date
4
7
13
19
pt
y
e2
g
l
e
n
u
S
Ju
A
Ju
2010
t
Oc
2
t
Oc
27
2009
4
9
6
3
2
7
9
ne July uly 2 ug 2 ept 1 ct 1 Nov
u
O
J
J
A
S
Date
2010
San Bernardino NF - Pinyon pine - 2079 m
Tree 2
100
80
Total Number MPB
Total Number MPB
100
Attacks
2009
3 Trees
4
9
7
29 g 23 t 17 t 12 ov 6
ly
t 2 une
y
u
l
c
p
J
N
Oc
O
J
Ju
Au
Se
San Bernardino NF - Pinyon pine - 2709 m
Tree 5
Emergence
2010
150
2
2009
Inyo NF - Foxtail pine - 2926 m
200
t
Oc
Max Min Air Temperature C
0
t2
2.0
30
40
0
2.5
40
Attacks
2009
5 Trees
40
50
40
Max Min Air Temperature C
150
140
Total Number MPB
Attacks
2009
6 Trees
Emergence
2010
2010
Date
Figure 3. Cumulative thermal energy (>12˚C) at several MPB
sites.
4
9
6
3
2
7
9
ne July uly 2 ug 2 ept 1 ct 1 Nov
u
O
J
J
A
S
Lake Tahoe Basin NF - Whitebark pine - 2932 m
250
200
1000
2009
2010
Lake Tahoe Basin NF - Western white &
Lodgepole pine - 2603 m
2000
9
1
4
0
0
1
1
0
8
3
9
9
7
2
2
4
e 2 uly 2 ug 2 ept 2 ct 2 ov 2 ec 2 an 2 eb 1 rch 2 pril 2 ay 2 ne 1 uly 1 ug 1 ept 1
n
O N
J
F a
J
J
A S
D
A S
M Ju
A
Ju
M
100
4
3
7
19
pt
e2
g1
ly
e
n
u
u
S
J
A
Ju
4
9
6
3
2
7
9
ne July uly 2 ug 2 ept 1 ct 1 Nov
u
O
J
J
A
S
Date
3000
0
0
t
Oc
4000
50
0
4
3
7
19
pt
e2
g1
ly
e
n
u
u
S
J
A
Ju
Lassen NF 1635 m
Tahoe Basin NF 2603 m
Tahoe Basin NF 2932 m
San Bernardino NF 2709 m
Pronotum Width (mm)
120
Attacks
2009
5 Trees
Mx Min Air Temperature C
Total Number MPB
140
300
Total Number MPB
160
Cumulative Air Temperature >= 12C
Lassen NF - Sugar pine - 1635 m
24
t7
13
19
p
y
e
g
l
e
n
S
Ju
Au
Ju
In 2009, we selected four areas in California to monitor MPB lifecycle timing, air
temperature, and phloem temperature of MPB-infested host trees. The four areas had
current MPB activity, and were chosen to provide a gradient of elevation with multiple
host tree species from northern to southern California: 1) Lassen NF, sugar pine
(Pinus lambertiana); 2) Tahoe NF and Lake Tahoe Basin NF, including three elevation
zones with P. contorta (lodgepole pine), P. monticola (western white pine), and P.
albicaulis (whitebark pine); 3) Inyo NF, foxtail pine (P. balfouriana); and 4) San
Bernardino NF, P. monophylla (Fig. 1).
At each site, temperature probes were attached to 3-5 trees to monitor phloem
temperatures hourly for the duration of the MPB lifecycle. Air temperature is also
being monitored. The timing of MPB attacks was monitored and recorded on the
lower bole of each sample tree at each site on at least a weekly basis. After the
completion of MPB flight, 1x2 ft emergence cages were attached to north and south
sides of each sample tree at each site. MPB emergence timing was monitored on
each tree beginning spring 2010. Coincident with emergence from 2009 attacked
trees, MPB attacks on live trees were monitored in 2010. Temperature probes were
attached to these trees and temperature will continually being monitored through
emergence in 2011. Trees were not probed at the Inyo NF site until October 2009. A
portion of temperature data from the Tahoe NF lodgepole pine site was lost due to
vandalism and datalogger malfunction.
Preliminary Results, cont.
5000
Total Number MPB
The geographic distribution of mountain pine beetle (Dendroctonus
ponderosae) (MPB) is extensive, encompassing all pine ecosystems from southern
California to central British Columbia. In recent years, MPB outbreaks have become
more intense and of longer duration, killing pines over millions of acres. This increase
in, and expansion of, MPB activity is thought to be a direct result of warming
temperatures and reduced precipitation. MPB fitness and population success are
directly related to temperature as it affects multiple life history strategies and
community associates. Future distributions of MPB (both expansions and
contractions) will be dictated by climate regimes in susceptible pine forests as well as
the ability of MPB to migrate and/or adapt to novel environments.
To describe and predict future trends in population success as a function of
temperature, models describing MPB phenology have been developed using data
derived from populations in central Idaho. However, little data is available on MPB
population dynamics in the southern part of its range, including many areas in
California, to evaluate the adequacy of current models. Constant temperature
laboratory experiments and range-wide genetic analyses have demonstrated
significant genetic and quantitative trait variation among MPB populations from
different latitudes, but how this variation relates to population success throughout
California is unclear. For example, the potential for MPB populations to successfully
complete two generations in a single year in current or predicted climate regimes of
California has not been investigated. California is home to six of the nine white pine
species native to the US. Many of these are keystone, long-lived species growing at
high elevations and are threatened by MPB and white pine blister rust. Baseline data
is needed on MPB temperature-dependent lifecycle timing to assess potential
impacts to high-value pine species caused by current and changing climates
throughout California.
Preliminary Results
Pronotum Width (mm)
Introduction
Emergence
2009
60
40
Attacks
2009
20
0
24
t7
13
19
p
y
e
g
l
e
n
S
Ju
Au
Ju
2009
t
Oc
2
t
Oc
27
e 9 uly 4 ly 29 g 23 pt 17 ct 12 ov 6
n
J
N
O
Ju
Ju
Au
Se
Date
2010
Figure 2. Weekly number of MPB attacks in 2009 and emergence in 2010,
summed for all trees at each site. MPB emergence numbers for Tree 2, San
Bernardino NF based on emergence holes. All other emergence numbers based
on tree cages. Attacks were measured on the entire circumference of the tree
bole between 1 and 6 ft. Emergence cages only sampled 4 sq ft. of this area.
• MPB was univoltine in all trees at all sites, with the
exception of Tree 2 at the San Bernardino site in 2009.
• Temperature was the warmest at the San Bernardino NF
pinyon pine site, and coolest at the Lake Tahoe Basin NF
whitebark pine site (Figs. 3, 4). At the San Bernardino NF
site, thermal energy was more than 3000 units greater than at
the Lake Tahoe NF whitebark pine site, although MPB was
univoltine at both sites.
• Size of emerged MPB adults varied among the sites.
Females were always larger than males. Beetles at the Inyo
NF site were the largest.
• MPB emergence will be monitored again in spring/summer
2011, resulting in data on two complete MPB generations at
each site.
• Data from multiple trees, sites, and years will be used to
evaluate our MPB phenology model for use in predicting
susceptibility of California pine forests to MPB outbreaks and
to develop management strategies and prioritize cone
collection for gene conservation.
Acknowledgements and Thanks: Stacy Hishinuma and Andreana
Cipollone – San Bernardino FHP; Brian Knox, Matt Hansen, RMRS;
Funding: WC-EM-09-02. Contact: Barbara Bentz bbentz@fs.fed.us.
Figure 1. Site locations