Biofuel Crops Eating Up US Grasslands, Study Says

Scientists and environmentalists have long warned that biofuel production could have troubling land-use consequences, and now there’s new research that appears to confirm some of the worst fears.

In a peer-reviewed article – disputed by the biofuels industry – researchers from South Dakota State University say some 1.3 million acres of grasslands in the “Western Corn Belt” running through the Dakotas, Minnesota, Nebraska and Iowa have been lost because “(h)igh corn and soybean prices, prompted largely by demand for biofuel feedstocks,” are encouraging farmers to plant crops on the land.

The irony here is that biofuels are sold by the industry a way to help protect Earth and its ecosystems from the likely ravages of climate change. Just last week, responding to president Obama’s call for action on climate change, the National Biodiesel Board put out a press release calling biodiesel “a practical, cost-effective and bipartisan solution that’s here today to address this problem.”

But the new study by Cristopher Wright and Michael Wimberly, published this week in the Proceedings of the National Academy of Sciences, says the loss of grasslands – native prairie and man-modified grasslands alike – could be having a devastating effect:

Across the WCB, more than 99% of presettlement tallgrass prairie has been converted to other land covers, mostly agricultural, with losses in Iowa approaching 99.9% of an original 12-million ha of tallgrass prairie. Potential expansion of corn and soybean cultivation into remaining fragments of tallgrass prairie in the WCB presents a critical ecosystem conservation issue.

None of this is news to environmental groups. Just a few weeks ago, Fuel Fix reported that Enviornmental Working Group joined with antipoverty activists and deficit hawks to call on Congress to reform the renewable fuel standard that drives ethanol production. EWG said corn ethanol was “not only … a disaster for consumers, most farms and taxpayers; it’s also been a disaster for the environment. In fact, it’s worse for the environment than the Canadian tar sands.”

The RFS technically does seek to move the country away from using food feedstocks for biofuels production, but cellulosic ethanol, using inputs like perennial crops such as switchgrass, has been slow to arrive. The authors sound like they are losing hope:

Even if recently converted grasslands were subsequently converted to perennial bioenergy crops, substantial carbon debts would still persist. With respect to conservation of biodiversity and wetlands, the maintenance of mixed-grass prairie as pasture, or possible harvest of mixed-grass prairie as a cellulosic biofuel feedstock, is clearly a preferable alternative to grassland conversion. However, the development of a cellulosic biofuel industry in the United States has been slow. The present study indicates that the window of opportunity for realizing benefits of perennial bioenergy crops may be closing in the WCB.

The industry is more optimistic about cellulosic ethanol‘s prospects. But apart from that, the industry maintains it is hardly clear that a push for more corn and soybeans for the current generation of biofuels is leading to grassland losses. According to a blog post by the Renewable Fuels Association:

The study’s findings stand in stark contrast to U.S. Department of Agriculture (USDA) acreage data, which show increased corn and soybean acres in the region have occurred via crop switching, not cropland expansion. Further, the extremely high rate of error associated with the satellite imagery used by the authors renders the study’s conclusions highly questionable and irrelevant to the biofuels policy debate.

Editor’s note: This article was updated after its original publication to add in the response from the Renewable Fuels Association.

Pete Danko is a writer and editor based in Portland, Oregon. His work has appeared in Breaking Energy, National Geographic's Energy Blog, The New York Times, San Francisco Chronicle and elsewhere.


  • Reply February 22, 2013


    The strength of this study is the measurement of land use change. However, the link to biofuels and the judgment on the value of biofuels policy is not supported by the data in this research and does not merit the headlines. A more accurate interpretation of the recent land use change is that farmers are once again finding it economical to grow food on cropland that was previously abandoned due to low commodity prices. Farmers are not tilling up virgin grasslands, but are instead putting land back to work that is being expelled from the Conservation Reserve Program due to Farm Bill budget cuts. Find more facts at:

  • Reply February 22, 2013

    The study referenced by this article does not quantify biofuel production at all or provide any substantive link between biofuels and land use change they measured. For a better study on biofuels see the University of Illinois paper at . Those researchers actually looked at biofuel production and found there is more than enough famrland available to meet our goals for energy independence.

    • Reply February 22, 2013

      Pete Danko

      Interesting study. Thanks for referencing it. It certainly makes an argument that there could and should be low-sensitive, low-carbon land available to grow biofuel feedstocks, although (from my reading) it doesn’t attempt to gauge what has actually been unfolding.

      • Reply February 22, 2013

        We need more journalists that actually read the studies. Here is another in-depth study concluding the environmental impacts of ethanol production are lower than those of petroleum; and “even though use of US corn for ethanol production increased five-fold from 2001 to 2009, improvements in corn yields were largely responsible for the overall increase in domestic production of corn, and the domestic market adjusted flexibly to ethanol roduction with minimal land-use change”

        • Reply February 22, 2013

          Pete Danko

          This study is a good reality check — a reminder that while biofuels production might have negative environmental impacts, those impacts could be less severe than would be incurred by continuing to rely on petroleum. But then there’s the question: Even if we concede a marginal benefit vs. petroleum, from a policy perspective, at what cost are we achieving it? There could be better ways to achieve the ultimate goals of reducing fossil fuel use and lowering greenhouse gas emissions. Jaeger ( has argued that “as a means of reducing fossil fuel use and GHG emissions, domestic production of biofuels in the U.S. is found to be 14 to 31 times as costly as alternatives like a gas tax or pomoting energy efficiency improvements.” So might we be better off putting our efforts behind more aggressively changing the transportation paradigm and shifting away from liquid fuels?

          • February 22, 2013


            We are going to need liquid fuel. The only alternative liquid to fossil fuel is biofuel. The U.S. biodiesel industry has a goal to displace 10% of our petroleum diesel by 2022. This leaves plenty of opportunity for efficiency improvements and other alternatives to whittle away at the other 90%. Advanced Biofuels like Biodiesel
            are a great value. The displacement of imports, domestic jobs and revenue they create pay back multiple dividends compared to
            the cost. This is in addition to significant environmental benefits and positive economic impacts for the food supply. Oak Ridge also quantified the economic benefits in this paper

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