Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/12/2010
Publication Date: 9/28/2010
Citation: Feyereisen, G.W., Camargo, G.T., Baxter, R.E., Baker, J.M., Richard, T.L. 2010. Biofuel Potential of Cellulosic Double Crops Across the U.S. Corn-Soybean Belt [abstract]. Sustainable Feedstocks for Advanced Biofuels Meeting. Available: http://www.swcs.org/en/conferences/sustainable_feedstocks_roadmap/submitted_posters/. Interpretive Summary:
Technical Abstract: Efforts by researchers and policy makers to reduce U.S. dependence on imported oil include investigation of biofuels derived from plant biomass, which raises concern over fuel vs. food competition. One solution that addresses the concern of fuel crops displacing food crops is to raise cellulosic double crops on the land base between summer crops. To date, winter rye (Secale cereale L.) has been inserted successfully into corn-corn, corn-soybean, and soybean-corn rotations to provide ecosystem benefits; however, the practice is economically unsustainable. This study was conducted to estimate the harvestable biomass from a winter rye cover crop on lands supporting corn and soybean crops, a practice that has potential to provide both ecosystem and economic benefits. We identified corn and soybean acreage in the U.S. by county using USDA NASS acreages and excluded irrigated land and acreage already supporting a winter small grain crop. We selected 30 locations within the identified region and calculated the winter rye biomass potential with RyeGro, a soil-plant-atmosphere simulation model developed for this purpose. Generated weather inputs from the 30 locations were used; fall and spring planting and harvest dates were derived from USDA state-based data. Average RyeGro biomass yields for a 23-year period for the 30 locations were used to develop a regression model based on temperature and precipitation. The regression model was then used to determine rye biomass potential in each county. The spatial analysis of crop land indicated that 18.4 million acres in continuous corn rotation and 78.2 million acres in a corn-soybean rotation are suitable for producing winter rye. The modeling results project that from 194 to 224 x 106 Mg (214 to 247 x 106 ton) of rye biomass can be harvested from this land base when the rye is harvested seven to two days prior to spring crop planting, respectively. Although additional analysis needs to be performed on the water quantity and quality impacts of widespread use of winter rye as a cellulosic double crop, the current study demonstrates the relatively sizable potential for this strategy to produce cellulosic biofuel with minimal risk to the primary food crop.