"Don't let invasive biofuel crops invade your country"

That's a quote from the International Union for Conservation of Nature, in this Elizabeth Rosenthal article. This spring has seen a backlash against biofuel generation based on its apparent impact on food prices. Among the most promising alternatives to starch or sugar-based ethanol production is cellulosic production from wild grasses or reeds.

The problem is that the perfect biofuel species -- one that grows easily in a variety of habitats, with little care, and possibly perennial so that it can be harvested year after year without repeated planting -- pretty much is the textbook definition of an invasive plant species.

The European Union is funding a project to introduce the "giant reed, a high-yielding, non-food plant into Europe Union agriculture," according to its proposal. The reed is environmentally friendly and a cost-effective crop, poised to become the "champion of biomass crops," the proposal says.
A proposed Florida biofuel plantation and plant, also using giant reed, has been greeted with enthusiasm by investors, its energy sold even before it is built.
But the project has been opposed by the Florida Native Plants Society and a number of scientists because of its proximity to the Everglades, where giant reed overgrowth could be dangerous, they said. The giant reed, previously used mostly in decorations and in making musical instruments -- is a fast-growing, thirsty species that has drained wetlands and clogged drainage systems in other places where it has been planted. It is also highly flammable and increases the risk of fires.

Well, burning the stuff certainly defeats the purpose. It seems to me that most of these drawbacks come from insisting on a monoculture, which -- if you have an efficient cellulose processing capacity -- I don't see why you care about. A real natural marsh or tallgrass ecosystem can't stand much mowing, but if you could tune a multispecies ecology for biofuel production, that would pose much less risk of invasive potential, and would be less trouble to look after. The tallgrass ecosystem was based on burning, anyway, so you should be able to maintain the soil while taking out hydrocarbons with minimal fertilizing.