New Study Shows Producers Where and How to Grow Cellulosic Biofuel Crops
(University of Illinois College of Agricultural, Consumer and Environmental Sciences/Science Daily) A new report provides practical agronomic data for five cellulosic feedstocks, which could improve adoption and increase production across the country. — … “Early yield estimates were based on data from small research plots, but they weren’t realistic. Our main goal with this project was to determine whether these species could be viable crops when grown on the farm scale,” says D.K. Lee, associate professor in the Department of Crop Sciences at the University of Illinois and leader of the prairie mixture portion of the study.
The project, backed by the U.S. Department of Energy and the Sun Grant Initiative, began in 2008 and includes researchers from 26 institutions. Together, they evaluated the bioenergy potential of switchgrass, Miscanthus, sorghum, energycane, and prairie mixtures in long-term trials spanning a wide geographical area. Due to shortages in plant materials, Miscanthus and energycane were grown on smaller plots than the other crops, but researchers say the new results are still valuable for producers.
No one feedstock “won” across the board. “It depends so much on location, nitrogen application rate, and year variability,” Voigt says. Instead of highlighting specific yields obtained in good years or locations, a group of statisticians within the research team used field-based yield and environmental data to create maps of yield potential for the five crops across the U.S. Dark green swaths on the maps represent areas of highest yield potential, between 8 and 10 tons per acre per year.
According to the new results, the greatest yield potentials for lowland switchgrass varieties are in the lower Mississippi valley and the Gulf coast states, whereas Miscanthus and prairie mixture yields are likely to be greatest in the upper Midwest.
Lee says the prairie mixtures, which are typically grown on CRP land to conserve soil, didn’t live up to their potential in the study. “We know that there are higher-yielding switchgrass varieties today than were included in the CRP mixtures in the study. If we really want to use CRP for biomass production, we need to plant highly productive species. That will bump yield up a lot higher.
Energycane could reach very high yields, but in a relatively limited portion of the country. However, the crop that shows the highest potential yields in the greatest number of locations is sorghum. The annual crop is highly adaptable to various conditions and might be easier for farmers to work with.
“It fits well in the traditional annual row-crop system; better than perennial crops. It may not be environmentally as desirable as perennial crops, but people could borrow money in winter to buy seed and supplies, then plant, and sell in the fall to pay back their loans. It’s the annual cycle that corn and beans are in,” Voigt says.
Lee adds, “In terms of management, sorghum is almost the same as corn. It germinates and grows so quickly, weed control is not a big issue. If you plant by early June, it will be 15-20 feet tall by September. It also has good drought tolerance.”
New study shows producers focuses on cellulosic biofuel crops (Journal Gazette and Times Courier)