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Benefits/Tradeoffs of Fuel Control Treatments
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FUNDED BY:
GNLCC
Benefits/tradeoffs of fuel control treatmentsWhat we have learned from SageSTEP so far
Bruce Roundy and Jim McIver
COLLABORATORS
Great Basin Biomes
Forest
WoodlandSage-Cheat
Salt Desert Shrub
Annual Precipitation
4’’ 12’’ 24’’
SageSTEP: Two Experiments
Wildfire is managing the landscape
1950 1960 1970 1980 1990 2000 20100
50,000
100,000
150,000
200,000
250,000
300,000
0
2,000,000
4,000,000
6,000,000
8,000,000
10,000,000
12,000,000National Interagency Fire Center data
FiresAcres
Nu
mb
er
of
fire
s
Ac
res
bu
rne
d
Treatments: Sagebrush SteppeSage-Cheat Experiment
Prescribed fire
Mowing
Herbicide – Tebuthiuron (Spike 20P) applied aerially
Control
Plateau pre-emergence herbicide (applied by hand-spraying) crossed with all four treatments for cheatgrass control.
Treatments Woodland Experiment
Prescribed fire Chainsaw Cutting
Bull Hog (in Utah only)
Control
Prescribed Fire
SageSTEP: Multivariate
Social Acceptance
Economics
Soil Carbon
Runoff & Erosion
Sage-Obligate Birds
Insect Biodiversity
Vegetation
Fuels, Fire Behavior
Initial 3-year resultsSpecial open source issue- September 2014
• 13 articles• Introduction and synopsis• 4 vegetation response• 3 soils, hydrology• 1 butterflies• 1 birds• 1 remote sensing, image
analysis• 1 social acceptance and
public trust
Sage-cheat fuels
• Fire and mowing reduced woody fuels• Herb. fuels decreased then rebounded
Pyke et al. 2014 REM
Woodland fuels
Prescribed fire
Wildfire
Mechanical
Wildfire
Wildfire
Cut and drop
Shred
Courtesy Brad Jessop
Treatment fuel effects
1 hr 10 hr 100 hr 1000 hr0
2000
4000
6000
8000
10000
30% Pretreatment Tree Cover
Untreated or CutBurnShred
Wo
od
y t
ree
fu
els
(k
g/h
a)
Young et al 2014 IJWLF
Fuel size classes
Diameter (mm)1 hr ≤ 610 hr 6-25100 hr 26-761000 hr >76
Avoiding wildfire damage after mechanical treatments may require prescribed fire
B
A
B
A
B
A
B
CB
C
C
A
C
C
CC
A
AB
A
A
A
B
A
A
A
BC
AB
A
AB
B
AB
B
-10
0
10
20
30
40
50
60
70
Cover
loss
(%
)
Control
Burn
Cut
Shred
Stansbury cover loss (%) 1 year after Big Pole fire
Roundy unpublished
Sage-cheat vegetation response• Fire reduced tall
grass biomass first year, then recovered
• Imazapic decreased cheatgrass and perennial grass cover for 3 years
• Sandy soil, lower whc associated with cheatgrass
• Concern for grass under shrubs and fire
Pyke et al. 2014 REM Reisner et al 2013 JAERau et al. 2014 REM
Resilience theory and practice-expanded woodlands
From Briske et al. 2008. http://jornada.nmsu.edu/sites/default/files/briskeSRM08.pdf
Pre-treatment vegetation
0 10 20 30 40 50 60 70 800
50
100
150
200
250
Herbaceous biomass (kg/ha)
Tree cover (%)
0 20 40 60 800
10002000300040005000
Shrub biomass (kg/ha)
Tree cover (%)
00.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
0
10
20
30
40
50
60
70
Relative cover (%)
CheatgrassForbShortTallShrubTree
Tree dominance index
Shrub cover
0 0.2 0.4 0.6 0.8 10
5
10
15
20
25
30
3 Years since treated
ControlBurnCut
Tree dominance index
Sh
rub
co
ve
r (%
)
0 0.2 0.4 0.6 0.8 10
5
10
15
20
25
30
6 Years since treated
ControlBurnCut
Tree dominance index
Sh
rub
co
ve
r (%
)
Roundy et al 2014 REM (3rd year results)
Residual trees and sagebrush seedlings
Sagebrushseedlings
0 1 2 30
0.20.40.60.8
Sagebrush seedlings/m2
ControlBurnCut
Years since treatment
Miller et al. 2014 REM (3rd year results)
Bybee et al submitted
Untreated Shred Shred-seed0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
B
A
A
Sagebrush seedlings/m2
Perennial herbaceous cover
0 0.2 0.4 0.6 0.8 10
5
10
15
20
25
30
35
40
3 Years since treated
ControlBurnCut
Tree dominance index
Pe
ren
nia
l he
rba
ce
ou
s c
ov
er
(%)
0 0.2 0.4 0.6 0.8 10
5
10
15
20
25
30
35
40
6 Years since treated
ControlBurnCut
Tree dominance index
Pe
ren
nia
l he
rba
ce
ou
s c
ov
er
(%)
Roundy et al 2014 REM (3rd year results)
Cheatgrass cover
0 0.2 0.4 0.6 0.8 10
2
4
6
8
10
12
14
3 Years since treated
ControlBurnCut
Tree dominance index
Ch
ea
tgra
ss
co
ve
r (%
)
0 0.2 0.4 0.6 0.8 10
2
4
6
8
10
12
14
6 Years since treated
ControlBurnCut
Tree dominance index
Ch
ea
tgra
ss
co
ve
r (%
)
Roundy et al 2014 REM (3rd year results)
Shredding increases cheatgrass cover; seeding suppresses it
0 20 40 60 80 1000
5
10
15
20
25
30
35Expansion woodlands
UntreatedShreddedShredded-seeded
Tree cover (%)
Ch
ea
tgra
ss
co
ve
r (%
)
Bybee et al submitted
Tree reduction increases soil water, N and P resources
0 1 2 3 4 5 6 7 850
60
70
80
90
100
110
120
Spring wet daysPhase III
ControlBurnCutShred
Years since treatment
0 1 2 3 4 5 6 7 8300
500
700
900
1100
1300
Spring wet degree daysPhase III
ControlBurnCutShred
Years since treatment
Roundy et al. 2014 REM 4th year results
Shredding increased:
• Time of soil water availability and temperatures
• Inorganic N
• Seedling biomass
Mound Interspace Mound Interspace Mound Interspace Mound Interspace0
50100150200250300350400450
Untreated Masticated
Spring-Summer Summer-Fall Winter All Seasons
Ino
rgan
ic N
(m
g m
-2 4
mo
-1) *
**
**
*
* *
Young et al. 2013FEM
Young et al. 2013REM
Roundy et al. 2014 REM
Young et al. 2014AESS
Treatment Effects on Available NitrogenTreeless Sagebrush Steppe
Rau et al. 2011. Transition from sagebrush steppe to annual influence on belowground carbon and nitrogen. Rangeland Ecology and Management 64:139-147
Percent of Potential Tree Cover
Percent of Potential Tree Cover
Carbon Management:Sequestration?
Tradeoff w/Vegetation?Rau, B.M. et al. 2012. Journal of Arid Environments 76:97-104.
Pierson, F.B. et al. 2010. Rangeland Ecology and Management 63:614-629. Pierson, F.B., et al. 2013. Rangeland Ecology and Management 66:274-289.
Williams, C.J., et al. 2013. Ecohydrology, doi: 10.1002/eco.1364
Hydrology
Hydrology• Erosion was site-
specific• Shredded mulch
reduced erosion• Interspace grass
recovery is key
Pierson et al. 2014 REM
Object-based image analysis accurately estimates:
• Canopy fuels using NAIP imagery Hulet et al. 2014 REM
• Treated fuels using high resolution 0.06-m pixel color IR Hulet et al 2014 EM
Woodland Ecotone SagebrushBird Community
OnaquiMechanical tree reduction supported sagebrush
birds
Knick et al 2014REM
McIver and Macke 2014REM
Butterfly response
• Diversity increased with treatment
• Melissa blue increase associated with increased nectar for larvae
• Juniper hairstreak declined
Public Acceptance and Trust
Shindler et al. 2011. Rangeland Ecology and Management 64:335–343.Gordon et al. 2014. Public priorities for rangeland management: A
longitudinal panel study of residents in the Great Basin. Rangeland Ecology and Management, in review.
Onaqui CUT
Pre-Cut -- 2006 Post-Cut -- 2007
Post-Cut -- 2009
Immediately Post-fire
Longer-term Effects? – Stay Tuned
Re-measurement scheduled for 2015.
6 Yr Post-fire
Tradeoffs
• Imazapic reduces cheatgrass and p. grass• Fire reduces fuels but increases cheatgrass and
erosion• Mechanical treatments maintain shrubs,
increase perennial herbaceous, decrease erosion (shredding), but keep fuels, future tree reduction needed
• Near complete tree reduction supports sagebrush birds near open sagebrush
• Perennial grasses are key to resilience• What will site analyses tell us?
SageSTEP Outreach Coordinator:Lael Gilbert, Utah State University
sagestep.org
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