Gas, Grass & Biomass

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As goes ethanol, so goes our landscape? On Sept. 6, the USDA’s chief economist announced that the U.S. would need 90 million acres of corn by 2010 to meet the burgeoning demand for ethanol while maintaining existing markets for exports and animal feed. That’s 10 million more acres than what farmers have been planting in recent years. Where will that extra corn come from? Well, 7 million acres could be raised on land that is currently covered in grass and other perennial plants as part of the Conservation Reserve Program (CRP), said the economist, Keith Collins. Such thinking makes a couple of troubling, and wrong, assumptions.

For one thing, Collins assumes that CRP land is currently just sitting “idle” and not serving much of a purpose other than as future corn ground. In fact, CRP has been one of the most successful farmland conservation programs in our nation’s history. About 36 million acres of cropland has been setaside as CRP. Much of that was land that was highly erodible or in other ways environmentally fragile. By replacing annual row crops with grasses and other perennials, CRP reduces erosion, protects water resources and traps carbon. I visited several farms in western and central Minnesota this summer that had used CRP to establish top quality wildlife habitat in odd corners—places that had not produced much of a crop in the past because of wet soils or the difficulty of maneuvering equipment in awkward spaces. I saw pheasants, deer, ducks, shorebirds and songbirds thriving in corn and soybean country. Farmers were talking excitedly about the hunting and wildlife watching opportunities that CRP ground was providing them and their children. Once that land is plowed up, all of those ecological services are lost.

Already there are concerns that as farmers with current CRP contracts consider renewing in coming years, they will opt instead to turn it back into row crops as promises of ethanol-inflated corn prices overshadow the relatively modest government setaside payments. Collins’ comments also come at a time when Congress is beginning to debate the 2007 Farm Bill. Will the CRP program, which is already under fire from multinational grain companies, be scaled back in the Farm Bill to make room for more corn-based ethanol?

Collins is also assuming corn ethanol is our only biofuels option. In fact, one of the most exciting areas of biofuel research and development is something called cellulosic ethanol. Whereas corn ethanol is made from the actual grain of the corn plant, cellulosic fuels can be cooked up from the other parts of a plant, such as the stalks of grasses and the woody material in trees. Unfortunately, an article in the August issue of Discover magazine chose to focus on how cellulosic technology could be used to make cornstalks into fuel. That would be an environmental disaster—cornstalks provide valuable protection to harvested cropland during the late fall and winter, while returning some organic matter to the soil. Making ethanol from the corn grain and the cornstalk would leave much of the Midwest looking like a dusty parking lot from November until May.

But making native perennial grasses, forbs and wood plants into cellulosic biofuels could provide many long term environmental benefits. Besides protecting the soil year-round, such stands could store carbon and provide excellent wildlife habitat. David Tilman is a University of Minnesota ecologist who has been working with an interdisciplinary scientific team to research how biofuels could be produced in environmentally and economically sustainable ways. Research out of the Department of Energy’s Oak Ridge National Laboratory shows that making fuel from switchgrass could be 15 times more energy efficient than corn-based ethanol. But planting monocrops of switchgrass isn’t the answer, says Tilman. He sees a time when large stands of diverse grasses and forbs will be grown for biofuels in Minnesota, replicating the native prairie ecosystems of the past. The excess biomass would be harvested in the fall for energy, leaving a permanent stand of perennial plants as ground cover and a future source of growth. This could be done on marginal farmland without high amounts of fertilizer, pesticides and energy, says Tilman. Cellulosic energy could offer a way for working farmland to produce numerous ecological, economic and energy-based services.

Several technical issues have to be worked out before cellulosic biofuel has its own car commercial jingle a la “Live Green, Go Yellow” (Note to Madison Avenue: “Pass Gas For Biomass” is available if you’re interested), but some promising real-world results are coming out of the Chariton Valley Biomass Project in Iowa. And a day after the USDA’s Keith Collins said CRP ground could be plowed up to make corn ethanol, U.S. Energy Secretary Samuel Bodman announced that commercial-scale cellulosic biofuel plants would be in operation within five years. In fact, the Department of Energy plans on issuing loan guarantees for the first such projects within a year.

All of this is a reminder of how much influence the USDA and the DOE can have on the look and feel of our landscape. Mr. Bodman and Mr. Collins need to get together and compare notes—soon.

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