The known unknowns—managing the invasion risk from biofuels

The uptake of second generation biofuels poses a range of risks including that of creating new invasive species. Plant invaders are a major threat to sustainability, economically and environmentally. Assessing the risk that plants will become invasive appears – paradoxically – to be attainable in practice, but difficult in theory. We explore the reasons for this, and inject a note of caution into the prospects for prediction. Instead, we endorse a precautionary approach, involving risk management and the phased scaling up of biofuel crops, accompanied by monitoring for untoward impacts, stringent analysis of prospective benefits, and the utilization of cultivated native species.

Research highlights► While biofuel crops may help solve our energy crisis, they pose a risk for our natural and agricultural ecosystems. ► Successful high impact invasions are low probability, but high impact, irreversible events. ► The past 15 years has seen the emergence of tools and frameworks for the assessment of plants for potential weediness. ► These tools achieve impressive accuracy, seemingly in the face of ecological theory. ► There is a number of measures that will help to manage the invasion risk of biofuels plants.