Submitted by Patricia McDaniels
UT Institute of Agriculture Marketing and Communications

Chad Hicks, of the UT Research and Education Center at Milan, evaluates the progress of a switchgrass plot.

Much is being said of the potential to exchange crops for gas, or more specifically to convert biomass into energy and biobased products. Ethanol and biodiesel are on the minds of producers, politicians, and consumers alike.

While ethanol is currently produced largely from corn, future predictions are that ethanol will be produced from wood and dedicated energy crops like switchgrass. Research by two economists with the University of Tennessee, Daniel G. De La Torre Ugarte and Burton C. English, indicates that the Mid South – in particular Tennessee – could play a huge role in meeting federally established renewable energy goals through the production of dedicated energy crops such as switchgrass.

Switchgrass is laden with potential energy. The native grass is a perennial that produces large yields that can be converted into energy by co-firing and through distillation into ethanol. Of all the high-yielding grasses, switchgrass is the most viable species for widespread use as a biomass crop in the United States.

The two researchers will present the details of their study at the 24th Milan No-Till Field Day sponsored by the University of Tennessee Agricultural Experiment Station on July 27 in Milan, Tennessee.

"We have the opportunity to lead the nation in the production of dedicated energy crops such as switchgrass," said English. The economist also maintains that producing dedicated energy crops will increase Tennessee and regional farm income and reduce soil erosion if done correctly.

Despite the extensive yield analyses, region-specific recommendations for the production of switchgrass are lacking. "Specifically," says Don Tyler, a professor of soil science with the University of Tennessee, "recommendations for Tennessee and Mid South soils and climate relative to seeding rate, nitrogen fertilization, and weed control were lacking."

Tyler and his associate Chris Walker with UT's Department of Plant Sciences, have spent the last several growing seasons measuring and comparing production data for switchgrass. The two will also discuss their findings to date at the Milan No-Till Field Day on July 27th.

"The lowland 'Alamo' variety of switchgrass has been naturally selected as the most suitable commercially available cultivar," said Tyler. "We compared Alamo with three selected cultivars, two from Georgia and one from Oklahoma. All three were more vigorous in growth habit as compared to Alamo and were higher yielding than Alamo on some of the four soil-landscape positions studied," he said.

Tyler and Walker also studied the interaction between seeding rate and nitrogen fertilizer rate. The effect of nitrogen and seeding rates varied across sites but on the most productive sites, the lower seeding and fertilizer rates were sufficient in the second growing season. Weed competition was one of the reasons for the low productivity of some sites, Tyler said.

Weed control research has been initiated by Larry Steckel, UT Extension assistant professor, for both the establishment year and second growing season, with emphasis on control of very competitive problem grasses such as broadleaf signalgrass and crabgrass. Weed control options have been identified but most are not currently legally labeled for switchgrass.

"If switchgrass becomes a viable alternative crop, we hope to have effective and economical production strategies developed," Tyler said.

Details about these presentations and a complete copy of the program for the Milan No Till Field Day are available online at http://milan.tennessee.edu.