Selecting Big Sagebrush Seed Sources for Restoration in a Variable
Environment: Assessment of Young Seedling Responses
Matt Germino, Martha Brabec, Brynne Lazarus, Ann-Marie
Raymondi, Bill Davidson, Lar Svenson
US Geological Survey
Forest & Rangeland Ecosystem Science Center, Boise ID
mgermino@usgs.gov
Bryce Richardson and Nancy Shaw of USFS RMRS, Anne Halford of BLM
Funded by GBNPSI project
Outline, studies of big sagebrush seeding or planting success:
• Landscape-scale experiments established in the Birds of Prey
National Conservation Area
-Testing importance of seed source, climate/weather
variability and herb treatments
-Focus on early establishment phase, comparing/contrasting
with adults
Seedling common garden also established in JFSP BOP
management-treatment study (funded by JFSP, GBNPSI,
FWS-GBLCC, local volunteers helped). Low survivorship;
best was in local basin big sagebrush & reduced herbs
Snake Plain Warming Study
-New approach for passive warming
in field experiments
Grand Teton
National Park
Birds of Prey
NCA,
burned and
unburned
Hollister, sagebrush
Raft River, burned
now cheatgrass
Passive Warming Frames
Open-side warming chambers increase longwave radiation balance,
simulating the Greenhouse effect, and raise minimum nighttime
temperatures by 2-4°C (Germino and Smith 1999).
Boise
EXPERIMENT AT BOP NCA:
• 5 replicated blocks on five
separate fires and paired
unburned sites
• Warming X Rainout
treatments
• 2012 wildfire sites: Poen,
Kave, South Point, Swan Falls,
and Coyote.
• Each sites has a different
fire/seeding history.
Seedling common-gardens now in BOP warming experiment
Table 1. Genotypes (provenances or populations) outplanted or seeded in Nov 20120 into
five sites in the BOP NCA that were burned by wildfire in June/July 2012.
Provenance State of
code name origin
IDT-2
ID
BOP-W
ID
IDV-2
ID
NMT-2
NM
UTT-1
UT
IDW-2
ID
ORT-2
OR
MTW-3
MT
ORV-1
OR
IDW-3
ID
IDV-3
ID
CAT-2
CA
Subspecies of
big sagebrush
tridentata
wyomingensis
vaseyana
tridentata
tridentata
wyomingensis
tridentata
wyomingensis
vaseyana
wyomingensis
vaseyana
vaseyana
Rationale (climate
of origin)
Local region
Local site
Local region
Warm/Dry
Cool/Wet
Local region
Warm/Dry
Cool/Wet
Cool/Wet
Warm/Dry
Cool/Wet
Warm/Dry
Treatments planted Ploidy
into
Warmed+Control
2N
Warmed+Control
4N
Warmed+Control
2N
Control
4N
Control
2N
Control
4N
Control
2N
Control
4N
Control
4N
Control
4N
Control
2N
Control
2N
Hypotheses and predictions
Warming effect:
negative impact on seedlings, esp. mountain big sage
Subspecies effect:
Mountain big sagebrush will have least establishment
Cytotype effect:
tetratploids will have greatest establishment
Provenance effect:
local populations will have greatest establishment
Climate of origin effect:
in winter, less stress for pops from colder areas.
Greater WUE in pops from warmer areas
Compared to adults:
similar variation among subspecies x ctyotypes;
greater stress exhibited by seedlings, different strategy
In adults: Great enhancement of warmer nights at higher
elevations; suggestive of potential for upward/northward
expansion perhaps with less contraction?
Growth (cm / year)
4
Control
Warmed
3
2
1
0
Boise
Twin Falls
Teton NP
but what about seedling life stage?
Strong species interaction:
1.0
0.8
BOP-W (A.t. wyomingensis)
60
Control
Warmed
0.6
40
0.4
20
0.2
0
IDT-2 (A.t. tridentata)
0.8
Height (mm)
Survival fraction
0.0
1.0
0.6
0.4
0.2
0.0
1.0
0.8
0.6
0.4
60
40
20
0
IDV-2 (A.t. vaseyana)
60
40
20
0.2
0.0
0
At BOP, survival of Wyoming big sagebrush is greatest in control plots.
BUT: Warming causes greater survival of basin and reduced growth of
Wyoming big sagebrush
Data: Martha Brabec
Fv/Fm
From 22 Jan ’14, P = 0.01
Control (21)
Warmed (37)
Treatment (and # surviving seedlings)
Survivorship (fraction)
0.8
ARTRT 2N
ARTRT 4N
ARTRV 2N
ARTRV 4N
ARTRW 4N
0.6
0.4
80
60
Height (mm)
1.0
40
IDV3
IDW2
IDW3
MTW3
NMT2
ORT2
ORV1
UTT1
20
0.2
0
0.0
Date (month/day)
Date (month/day)
Examples of species comparisons in control plots:
-Ploidy appears to have an effect on survivorship (P<0.05)
-Non-local basin big sagebrush has greater growth
Climate of Origin
Cool/Wet
IDV3
MTW3
UTT1
Local
IDW2
BOPW
IDT2
IDV2
Warm/Dry
IDW3
NMT2
ORT2
Survival_1-22-14
23
7
10
6
36
15
12
5
4
21
11
3
7
Parallel subspecies x cytotype patterns in seedlings & adults
75
0.75
Height (mm)
Survivorship
1
SEEDLINGS
50
0.5
25
0.25
0
0
Tri 2N Tri 4N Vas 4N Wy 4N Vas 2N
ADULTS
50
0.75
Height (cm)
Survivorship
1
Tri 2n Tri 4n Vas 4n Wyo 4n Vas 2n
0.5
0.25
0
Tri 2n Tri 4n Vas 4nWyo 4nVas 2n
Subspecies x ploidy
25
0
Tri 2n Tri 4n Vas 4n Wyo 4n Vas 2n
Subspecies x ploidy
Survivorship
Average Height (mm)
Growth vs. survivorship tradeoff in seedlings (but not adults)
100
ARTRW
ARTRT
75
50
25
0
0.4
0.2
0
Population
ARTRV
stress levels for seedlings still in conetainers after
frost in Nov 2012, adults at Orchard common garden
p<0.01
Fv/Fm
January 2012, similar results from controlled freezing experiment
Cool/wet
Local
Warm/dry
Climate of Origin
P < 0.05
Freezing point (C)
P < 0.05 for both.
Post freezing+sunlight FvFm
Seedlings have less
avoidance but better
resistance to freezing
ADULTS
SEEDLINGS
Subspecies and cytotype
Carbon isotopes:
• Greater water-use efficiency in populations
from warmer and drier climates (1 per mil, P <
0.05)
• Subspecies x cytotype variations are similar to
in adults, among subspecies, and also
cytotypes:
Preliminary outcomes
(Given overall low survival due to drought):
Warming effect:
Reduced physiological stress for all seed sources
Survival/growth: ATW > in controls, ATT> in warmed
Subspecies effect:
Mountain big sagebrush had least establishment
Cytotype effect:
Greater survival in 4N;
Provenance effect:
Local survivorship > in herb treatments, Local growth <.
Survival better in local than pops from other climates
Unclear on physiological stress differences
Greater WUE in pops from warmer areas
Compared to adults:
similar variation among subspecies x ctyotypes;
different growth/survival & freezing avoidance/resistance
Preliminary implications from climate studies
- Seed source effects are evident for initial establishment
- Some evidence for “local is better” for survivorship; but
opposite is true for growth
- Subtle warming may begin to shift subspecies suitability for
BOP NCA
- Care needs to be taken in translating info from reproductively
mature plants to problems of initial establishment;
Other relevant directions
Restoring structure to ameliorate microclimate for restoration
What can we learn about seed source effects from historic
seedings (do they indicate seed transfer limits?)
w/ Ann Marie Raymondi
7,492 seeding treatments
recorded in LTDL from
1940 to 2011, many areas
still needing updates
JUSTIN WELTY, USGS
Key Challenge in Identifying Treatments:
Increasing size and intensity of wildfires has burned over dozens of ESR
treatments in Southwestern Idaho from 1990-present.
21 seedings now evaluated near
Boise since Nov 2013, includes
Lysne&Pellant (2006) sites
Initial Findings
•
•
•
•
•
Seed typically from higher elevation ~ 500 miles away
One to many seed sources used
6 out of 21 seedings had correct ssp
4 of 21 seedings had decent establishment
Crude, very preliminary regressions not showing
geographic distance or elevation of seed source relates
to establishment
• More projects need to be sampled to account for
many factors
Excluding all the seeding treatments
that have burned over, estimated # of
additional projects we could sample:
Field Office
Shoshone
Burley
Jarbidge
Pocatello
Upper Snake
# seeding
# seeding
projects with projects with
complete info just Lot ID
2
9
1
11
4
2
0
3
3
6
We have sampled 20, there are 65 more we
could evaluate in Southern Idaho alone.
Seed may be available to asses what was planted on failed seedings
The end
mgermino@usgs.gov
Approp seed source, subspecies:
6 matches
12 wrong ssp
2 in question
1000
100
10
1
0
100
200
300
400
500
600
1000
100
10
1
-5000
-4000
-3000
-2000
-1000
0
1000
2000