INVASIVE WEEDS AND BIOENERGY CROPS:
ECONOMIC BOON OR ENVIRONMENTAL DISASTER?
Jacob Barney
Assistant Professor
Invasive Plant Ecology
[email protected]
Energy Independence and Security Act 2007
160
140
Billions of liters
120
100
80
16 Billion gallons
60
40
20
0
2007
2010
Conventional
2013
Cellulosic
2016
Biodiesel
2019
Other
2022
22 million acres: cropland
41 million acres: pasture
200,000 acres by 2014
Cellulosic portfolio
switchgrass
miscanthus
switchgrass
poplar
switchgrass
miscanthus
reed canarygrass
poplar
switchgrass
willow
sorghum
eucalyptus
Arundo
poplar
eucalyptus
black locust
switchgrass
miscanthus
sorghum
Saccharum
Cellulosic portfolio
switchgrass
miscanthus
switchgrass
poplar
switchgrass
miscanthus
reed canarygrass
poplar
switchgrass
willow
sorghum
eucalyptus
Arundo
poplar
eucalyptus
black locust
switchgrass
miscanthus
sorghum
Saccharum
The bioenergy ideotype
Life history
– Perennial
– High aboveground biomass production
– Flowers late / little allocation to seed production
Physiology
– Tolerates
• Drought
• Low fertility
• Saline soils
– C4 photosynthetic pathway
– High water/nutrient use efficiency
Other
– Highly competitive (reduces herbicide use)
– Few resident pests (reduces pesticide use)
– Allelopathic
– Re-allocates nutrients to roots in fall
“the thin green line”
Crying wolf, or legitimate concern?
WHAT IS AN INVASIVE SPECIES?
“.. (non-native) species whose introduction does, or is
likely to cause economic or environmental harm or
harm to human health.”
EO 13112
Invasive Plant Impacts






Reduce native species 
diversity
Increase fire frequency 
Increase flooding

Alter successional

patterns
Alter nutrient cycles 
Increase soil salinity 
Disrupt trophic
interactions
Reduce pollinators
Disrupt mutualisms
Increase management
costs
Reduce recreation
ad infinitum…
Origins of Invasive Plants
85% of invasive woody species from
landscaping
63% of Cal-IPC’s most invasive species have
horticultural origin
69% of FL-EPPC’s list have horticultural origin
Invasive species economics:
$120 billion (US)
$1.4 trillion (global)
We know how
this movie
ends…
• fast growing
• deep rooted
• no pests
• tolerates disturbance
85 MILLION SEEDLINGS PLANTED
“for the most part, successful invasion is forever”
-- Dan Simberloff
How Will Genetic Modification
Affect Potential Invasiveness?
• Yield Improvement
• Crop adaptation to marginal lands
• Increase amenability to bioprocessing
• Multi-product development
• Drought tolerance
• Salt tolerance
• Herbicide resistance
• Increased cellulose content
• Increased yield
• Water-use-efficiency
• Nutrient-use-efficiency
How Will Genetic Modification
Affect Potential Invasiveness?
• Yield Improvement
• Crop adaptation to marginal lands
• Increase amenability to bioprocessing
• Multi-product development
• Drought tolerance
• Salt tolerance
• Herbicide resistance
• Increased cellulose content
• Increased yield
• Water-use-efficiency
• Nutrient-use-efficiency
“they were the outcome of
a series of ingenious
biological meddlings--and
very likely accidental, at
that."
--Bill Masen
Day of the Triffids (1961)
Preventing unintended
consequences
Invasion arithmetic
Exotic
Most of our worst invasive sp. were
intentionally introduced
“weedy” characters
Thousands of acres as a propagule source
Transporting across diverse land use types
relatively high probability of invasion
Putting invasions in context
1. Most introduced species do not
become invasive
2. Invasiveness is not universal
3. Populations are invasive, not
species
4. All species have a non-zero
invasive probability
0
100
Invasive probability
Food, Conservation, and Energy Act 2008
Title IX: Sec. 9011: Biomass Crop Assistance
Program
Eligible crop does not include:
“any plant that is invasive or noxious or
has the potential to become invasive or
noxious, as determined by the Secretary,
in consultation with other appropriate
Federal or State departments and
agencies.”
H.R. 2419-406
Executive Order 13112
“ prevent the introduction of invasive
species and provide for their control
and to minimize the economic,
ecological, and human health impacts
that invasive species cause”
EPA vs Executive Order 13112
RIN (Renewable Identification Number)
Camelina sativa
switchgrass
Energy cane
miscanthus
“We are not finalizing….giant reed (Arundo donax) or napier grass (Pennisetum purpureum)”
Native to US
Noxious
Yield
(ton acre-1)
Giant reed
Arundo donax
exotic
4 states
20 - 40
Giant
miscanthus
Miscanthus ×
giganteus
exotic
-
12 - 20
Chinese
silvergrass
Miscanthus
sinensis
exotic
1 state
?
Energy cane
Saccharum
hybrid
exotic
-
12 - ?
Sugarcane
Saccharum
spp.
exotic
-
32
Elephantgrass Pennisetum
purpureum
exotic
-
20 - 40
Switchgrass
Panicum
virgatum
native
(briefly listed
in CA)
4 - 12
Mis-cane
Miscanthus x
sugarcane
exotic
-
?
Native to US
Noxious
Yield
(ton acre-1)
Giant reed
Arundo donax
exotic
4 states
20 - 40
Giant
miscanthus
Miscanthus ×
giganteus
exotic
-
12 - 20
Chinese
silvergrass
Miscanthus
sinensis
exotic
1 state
?
Energy cane
Saccharum
hybrid
exotic
-
12 - ?
Sugarcane
Saccharum
spp.
exotic
-
32
Elephantgrass Pennisetum
purpureum
exotic
-
20 - 40
Switchgrass
Panicum
virgatum
native
(briefly listed
in CA)
4 - 12
Mis-cane
Miscanthus x
sugarcane
exotic
-
?
Arundo donax
Noxious weed in California, Texas, Nevada
Proposed noxious weed in North Carolina (defeated)
Giant reed (Arundo donax)
$25,000 per acre to control
Weed Risk Assessment
Giant Reed - Arundo donax
Reject
Invasion history in
California / Texas
Miscanthus - Miscanthus x giganteus
Accept
No invasion history
WHY the difference?
Both are sterile, exotic, large statured, rhizomatous grasses
Barney & DiTomaso 2008 BioScience
If it hadn’t been planted in the
streams would it still be a problem?
Putting invasions in context
1. Most introduced species do not
become invasive
2. Invasiveness is not universal
3. Populations are invasive, not
species
4. All species have a non-zero
invasive probability
0
100
Invasive probability
NOT ALL LOCATIONS ARE EQUALLY SUITABLE
Miscanthus sinensis
Arundo donax
Pennisetum purpureum
Sorghum bicolor
not suitable
low suitability
moderate suitability
high suitability
high suitability + irrigation
Barney & DiTomaso (2011) PLoS ONE
Giant reed (Arundo donax)
Barney & DiTomaso (2011) PLoS ONE
Barney & DiTomaso (2011) PLoS ONE
Giant reed (Arundo donax)
- USDA APHIS found ‘high risk’: DID NOT REGULATE
- North Carolina petitioned to regulate: DID NOT REGULATE
- Oregon petitioned to regulate: DID NOT REGULATE
Barney & DiTomaso (2011) PLoS ONE
Barney & DiTomaso (2011) PLoS ONE
biofuel supply chain
Crop selection /
Breeding / GMO
CONVERSION
FIELD
STORAGE
HARVEST
TRANSPORT
The alfalfa “invasion”?
Species selection
corn
Miscanthus
× giganteus
noninvasive
johnsongrass
invasive
Napier grass
Arundo
Naturalized miscanthus
BCAP project
EDDMapS. 2011. Early Detection & Distribution Mapping System. The University of Georgia - Center for Invasive Species and Ecosystem
Health. Available online at http://www.eddmaps.org/; last accessed October 25, 2011.
WILL BIOENERGY CROPS FALL UNDER EXISTING
REGULATIONS?
State Weed Laws
• 46 states maintain noxious weed lists
• Some states also maintain seed laws (primarily
for seed purity)
• Listed taxa range: 0 – 264 (ū = 49)
• Some states also list federal taxa
Quinn et al. 2013 BioScience
Listed noxious weed species
149
30
11
15
91
264
36
48
223
5
28
25
72
70
9
12
32
38
8
27
14
9
8
3
13
15
7
11
3
122
139
96
15
31
10
19
18
4
0
6
106
122
124
1
NY
NJ
GA
RI
93
82
plants.usda.gov
Quinn et al. 2013 BioScience
Failure to Regulate Invasive Plants as Noxious
Alaska
Maine
Washington
North Dakota
Montana
Oregon
Minnesota
Wisconsin
South Dakota
Idaho
Vermont
New Hampshire
Massachusetts
New York
Rhode Island
Connecticut
Michigan
(upper penninsula)
Michigan
Pennsylvania
Wyoming
Iowa
Nebraska
Illinois
Nevada
Utah
Colorado
Indiana
Ohio
West
Virginia
Kentucky
Kansas
Virginia
Tennessee
California
Oklahoma
Arizona
New Mexico
Louisiana
Florida
Average
= 19.6%
0–
24%
South Carolina
Arkansas
Mississippi Alabama Georgia
Texas
Poor representation
of invasive plants
on noxious lists
Delaware
Maryland
North Carolina
Missouri
Hawaii
New Jersey
25 –
49%
50 –
74%
75%
+
No state invasive plant list
Strong representation
of invasive plants
on noxious lists
Quinn et al. 2013 BioScience
New (non GM) plant for commercial release
Current system
Is it regulated as a noxious weed?
No
Yes
Regulated:
No commercialization
OK to
commercialize
Quinn et al. 2013 BioScience
New (non GM) plant for commercial release
Current system
Is it regulated as a noxious weed?
No
Yes
Proposed system
ISC Weed Risk Assessment
Regulated:
No commercialization
OK to
commercialize
Quinn et al. 2013 BioScience
New (non GM) plant for commercial release
Current system
Proposed system
Is it regulated as a noxious weed?
No
Yes
Regulated:
No commercialization
ISC Weed Risk Assessment
Noxious:
High WRA /
2° review
Watch:
High WRA /
Mod 2° review
Caution:
EF WRA /
Low 2° review
Low Risk:
Low WRA /
Low 2° review
OK to
commercialize
Quinn et al. 2013 BioScience
New (non GM) plant for commercial release
Current system
Proposed system
Is it regulated as a noxious weed?
No
Yes
Regulated:
No commercialization
OK to
commercialize
ISC Weed Risk Assessment
Noxious:
High WRA /
2° review
Watch:
High WRA /
Mod 2° review
Caution:
EF WRA /
Low 2° review
Low Risk:
Low WRA /
Low 2° review
No liability
Regulated:
No release
Introduced
as is
Quinn et al. 2013 BioScience
New (non GM) plant for commercial release
Current system
Proposed system
Is it regulated as a noxious weed?
No
Yes
Regulated:
No commercialization
OK to
commercialize
ISC Weed Risk Assessment
Noxious:
High WRA /
2° review
Watch:
High WRA /
Mod 2° review
Caution:
EF WRA /
Low 2° review
Low Risk:
Low WRA /
Low 2° review
No liability
Regulated:
No release
Introduced
as is
Becomes invasive
Subject to liability
litigation
Quinn et al. 2013 BioScience
New (non GM) plant for commercial release
Current system
Proposed system
Is it regulated as a noxious weed?
No
Yes
Regulated:
No commercialization
OK to
commercialize
ISC Weed Risk Assessment
Noxious:
High WRA /
2° review
Watch:
High WRA /
Mod 2° review
Caution:
EF WRA /
Low 2° review
Low Risk:
Low WRA /
Low 2° review
No liability
Regulated:
No release
Introduced
as is
Due diligence in field
testing / BMPs
Becomes invasive
Subject to liability
litigation
Quinn et al. 2013 BioScience
What are others doing??
Application
• $50 application fee (for each non-contiguous
planting)
• Cover letter / letter of intent
• Proof of site ownership
• Voucher specimen of plant
• Description of plant, estimated cost of removal
and basis for calculation
Requirements
•
•
•
•
•
•
•
•
NOT ALLOWED for state/federal noxious weeds
≥2 contiguous acres
Traps / filters must be created
Equipment should be cleaned
Wildfire protection
Quarterly site visits by division inspectors
Permit holder required to destroy planting
Surety bond required (150% of cost)
The misinformed “Mad Men”
How do we prevent cultivating the next
invasive species?
1. Reduce Escape Risks
2. Determine the most appropriate
areas for cultivation
3. Identify plant traits that contribute
to or avoid invasiveness
4. Prevent dispersal
5. Develop Early Detection and Rapid
Response (EDRR) plans and rapid
response funds.
6. Develop eradication protocols for
rotational systems or abandoned
populations.
DiTomaso et al. 2010 Env Sci Tech
Mitigation through Best Management Practices
(BMP)
1
2
3
4
5
Right Plant, Right Place
Field Management
Responsible Harvest
Mindful Transportation
Sensible Storage
Bioenergy balance sheet
Bioenergy
crop
Invasive
species
Hydraulic fracturing
“Fracking”
Energy solution cost-benefit
- NO zero risk options
- ALL bioenergy crops pose some invasion
risk
- Lower yielding crops require more land
- Use of best management plans to
reduce invasion risk
Cannot have high yield, low
input, low land requirement, no
invasion risk bioenergy
Switchgrass = 8.5M
Arundo = 1.8M
Special Thanks:
Joe DiTomaso
Jeremiah Mann
Guy Kyser
Larissa Smith
Dan Tekiela
Ryan Dougherty
Lauren Quinn
Bryan Endres
James McCubbins
Matt Ho
Kevin Hensler
Eugene Dollete
[email protected]
http://www.ppws.vt.edu/~jnbarney