Biofuels: Cultivating Energy, not Invasive Species 

Approved by the Invasive Species Advisory Committee (ISAC) on August 11, 2009 

ISSUE 

To provide alternatives to petroleum-based energy, the United States (U.S.) government has 

mandated a greater proportion of plant-based biofuels be integrated into its energy portfolio. However, 

certain plant species being proposed for biofuel production in the U.S. are invasive species or 

are likely to escape cultivation and become invasive. 

U.S. Executive Order (E.O.) 131121

 defines invasive species as “alien [non-native] species whose 

introduction does or is likely to cause economic or environmental harm or harm to human health” and 

states: 

“Each Federal agency whose actions may affect the status of invasive species shall, to 

the extent practicable and permitted by law” “not authorize, fund, or carry out actions 

that it believes are likely to cause or promote the introduction or spread of invasive 

species in the United States or elsewhere unless, pursuant to guidelines that it has 

prescribed, the agency has determined and made public its determination that the benefits 

of such actions clearly outweigh the potential harm caused by invasive species; and that 

all feasible and prudent measures to minimize risk of harm will be taken in conjunction 

with the actions.”

The socio-economic and ecological costs of certain biofuel crops could greatly exceed their benefits. 

Thus, the Federal government needs to take strategic action to avoid inadvertently facilitating the 

introduction and spread of invasive species through its development, encouragement, funding, or 

other support of biofuels programs. 

ACTION 

This briefing paper, adopted by the U.S. Invasive Species Advisory Committee (ISAC) on August 11, 

2009, provides: 

a) background information on the potential linkages between biofuels and invasive species and; 

b) recommendations for Federal action to reduce the risk of invasive species introduction and spread 

through its biofuels programs. Implementation of these recommendations will help to ensure that 

the U.S. maximizes the benefits of its biofuel initiatives while preventing the spread of invasive 

species. 

 

1 www.invasivespecies.gov (see E.O. 13112 and the ISAC Definitions White Paper) 

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BACKGROUND

Agency Roles and Responsibilities 

Depending on their mission, Federal agencies might engage in biofuel programs by: 

 conducting biofuel research and development; 

 introducing and producing biofuel crops for experimentation and/or use; 

 subsidizing biofuel research, development, production, and marketing; 

 purchasing biofuels to supplement their energy demands; 

 establishing early detection and rapid response programs for escaped biofuel plants; 

 implementing long-term management of biofuel crops that become invasive; and/or regulating 

various aspects of the biofuels pathway, when necessary.

Policy and Legal Responsibilities 

Specific agency directives for biofuel programs are emerging in Federal legislation. For example, the 

2007 Energy Independence and Security Act (EISA) mandates the production of 61 billion liters of 

plant cellulosic-based fuels. This cannot be met with current agricultural, forestry, and municipal 

residues alone. It necessitates large-scale planting of dedicated energy crops that do not compete 

with food or feed. This will require producing and promoting biofuel crops for experimentation and 

demonstration. The U.S. Department of Agriculture's (USDA) research effort is therefore focused on 

identifying crops that will maximize yield while allowing cultivation on less productive, marginal lands 

with minimal agricultural inputs. The Food, Conservation, and Energy Act of 2008 (i.e., 2008 US Farm 

Bill P.L. 110-234) also directs USDA to provide subsidies for growers to encourage adoption of 

dedicated energy crops which currently do not have a market. The 2008 Energy Act directs the U.S. 

Environmental Protection Agency (EPA), in consultation with USDA and the Department of Energy 

(DOE), to report to Congress on the environmental and resource conservation impacts of biofuels 

Invasive Species Risk 

This paper focuses on one potential negative impact of 

biofuels, namely the risk that they will escape 

cultivation and become invasive species. Although 

most of our food, fiber, and landscape plants are nonnative species and relatively few have proven invasive, 

those that are harmful have caused substantial socioeconomic and environmental impacts (e.g., 

johnsongrass [Sorghum halepense] and kudzu 

[Pueraria montana])(Box 1). A number of potentially 

harmful non-native algal species are being considered 

for use in the production of biodiesel, renewable 

biodiesel, and jet fuel (e.g., the toxic freshwater 

cyanobacteria, Anabaena circinalis). (first report due 

Dec.2010). 

Box 1. Economic Impact of Invasive 

Plants in the U.S.2 

Estimated losses and the cost of control 

is $34 billion annually. 

 $26.4 billion on agricultural invasives 

 $6 billion on pasture invasives 

 $1.5 billion on turf and garden 

invasives 

 $0.1 billion on aquatic invasives 

2 Pimentel et al. 2000. BioScience 50:53-65. Note: Paper largely 

addressed managed systems. Additional research is needed for 

natural areas. 

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Indications that some biofuel crops pose a 

particular risk of becoming invasive include: 

Certain plant species proposed for biofuel production 

(e.g., reed canarygrass [Phalaris arundinacea], giant 

reed [Arundo donax], and miscanthus [Miscanthus

sinensis]) are already invasive in regions of the U.S. 

and/or elsewhere in the world.

Several of the traits that could maximize biofuel crop 

yield and foster the ability for biofuels to be cultivated in 

marginal environments can also increase risk of 

invasiveness. Invasive plants share many of the traits 

desired in biofuel crops and these traits may allow them 

to grow on marginal lands (Box 2).

The potential scale of biofuel cultivation (>61 million ha) 

suggests ample opportunity for biofuel crops to be 

introduced into environments in which they could thrive and interact with ecosystems. 

Box 2. Traits that maximize crop yield 

and increase risk of invasiveness 

 Perennial growth form 

 Rapid and high aboveground 

biomass production 

 Tolerance of drought, low fertility, or 

saline soils 

 Highly competitive with other 

vegetation 

 Few resident pathogen or insect 

Absent strategic mitigation efforts, there is substantial risk that some biofuel crops will escape 

cultivation and cause socio-economic and/or ecological harm. If invasion occurs, the costs 

associated with the damage may negate the economic benefits conveyed by cultivation of the 

particular species. The risks are particularly significant where biofuel crops are cultivated within 

ecosystems that include forest, prairie, desert, and wetland areas, as well as rangelands and other 

agricultural croplands. 

RISK MITIGATION AND RECOMMENDATIONS 

To minimize the risk of biofuel crop escape into the surrounding environment, the U.S. government 

needs to employ and promote ecological studies and scientific models that characterize the 

invasion risk of each biofuel species or cultivar (as appropriate) within a target region and identify 

ecosystems most susceptible to invasion. Information generated from biofuel crop ecological studies, 

risk analyses, bioeconomic and climate match modeling, and other methods can guide the 

government’s risk mitigation plans. Depending on their authorities, Federal agencies can take 

strategic steps at appropriate points within research and development, crop production, harvest and 

transportation, conversion/refinery practices, and/or regulatory action to minimize the risk of biofuel 

crops becoming invasive. ISAC recommends that the Federal government apply the following 

recommendations to its own biofuels programs, as well as use them as a basis for standards of 

operation when engaging with the private sector and other partners. 

Recommendation #1. Review/Strengthen Existing Authorities. 

Identify Federal authorities relevant to biofuels. Determine their likely influence on biofuel 

invasiveness (i.e., prevention or facilitation). Identify gaps and inconsistencies in authorities 

within and among Federal Departments or Agencies. As appropriate, develop policies and 

programs to minimize invasion risk.

Recommendation #2. Reduce Escape Risks. 

In order to determine potential biofuel benefits and risks, the invasive potential of each 

candidate biofuel crop needs to be evaluated in the context of each region proposed for its 

production. Use/promote species (including unique genotypes) that are not currently invasive 

and are unlikely to become invasive in the target region. Choose species or cultivars with a 

low potential for escape, establishment and negative impact. Where appropriate, implement 

mitigation strategies and plans to minimize escape and other risks. 

 

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Recommendation #3. Determine the Most Appropriate Areas for Cultivation. 

Ideally, biofuel crops should be propagated in containable systems (e.g., terrestrial or aquatic 

sites constructed specifically to cultivate biofuel crops) and be unable to survive outside of 

cultivation. Use research findings to identify the most appropriate sites (e.g., unlikely to impact 

sensitive habitat or create disturbances that will foster invasion) for cultivation of biofuel crops 

within landscapes. Support for biofuel research and demonstration projects will require site 

selection that minimizes the potential escape of plant species or cultivars to sensitive areas 

and the loss of wildlife habitat.

Recommendation #4. Identify Plant Traits that Contribute to or Avoid Invasiveness. 

Incorporate desirable traits (e.g., sterility or reduced seed production, inability to regenerate by 

stem fragments) into biofuel varieties to minimize their potential for invasiveness. Use 

information from plant research, agronomic models, and risk analyses to guide breeding, 

genetic engineering, and variety selection programs.

Recommendation #5. Prevent Dispersal. 

Develop and coordinate dispersal mitigation protocols prior to cultivation of biofuel plants in 

each region or ecosystem of consideration. Implement a comprehensive plan, appropriate to 

the specific crop, throughout the cultivation period. Examples of dispersal mitigation measures 

include the use of sterile cultivars, species not likely to genetically mix with other plants 

(different species or cultivars), harvesting prior to seed maturity, cleaning equipment, and 

minimizing propagule dispersal throughout the biofuel production cycle. 

Recommendation #6. Establish Eradication Protocols for Rotational Systems or 

Abandoned Populations. 

Proactively develop multiple year eradication protocols to plan for the rapid removal of biofuel 

crops if they disperse into surrounding areas or become abandoned or unwanted 

populations (e.g., those which persist beyond desired crop rotation period). 

Recommendation #7. Develop and Implement Early Detection and Rapid Response 

(EDRR) Plans and Rapid Response Funding. 

Develop EDRR plans that cover multiple years to eliminate or prevent establishment and 

spread of escaped invasive populations. A flexible funding source needs to be in place to 

support EDRR efforts. 

 

Recommendation #8. Minimize Harvest Disturbance. 

Disturbed environments are especially prone to plant invasion. Minimize the soil disturbance 

resulting from biofuel harvest by rapidly replanting, using cover crops, or employing other 

methods that will prevent the potential for future invasion of non-native plants from the 

surrounding area into the harvested site. 

Recommendation #9. Engage Stakeholders. 

Identify and employ cooperative networks (e.g., working groups and councils), communication 

forums, and consultation processes through which the Federal agencies can work with state 

agencies, tribes, the private sector, and other stakeholders to reduce the risk of biological 

invasion via the biofuels pathway.