Mules and Miscanthus: U of I Team Offers Growing Tips for New Biofuel Crop
Published: Sep. 6, 2007
URBANA - John Caveny, a Piatt County farmer, compares Giant Miscanthus to a mule.
Giant Miscanthus, a tall, perennial grass, is the sterile cross between two plants, and a mule is the sterile result of a cross between a horse and a donkey. The $1 million question is whether Giant Miscanthus, like a mule, can take on a heavy load - in this case, the job of freeing the U.S. from its dependence on overseas petroleum. Giant Miscanthus is one of the leading candidates for cellulosic ethanol production.
University of Illinois researchers have successfully established Giant Miscanthus at northern, central and southern Illinois sites, ranging from DeKalb to Dixon Springs. The following are some of the lessons learned on these sites, compiled by Tom Voigt, a U of I Extension specialist, and crop scientist Stephen Long, along with three graduate students:
PLANTING POINTERS. Large plantings of Giant Miscanthus are typically established using rhizomes. Based on U of I findings, you should plant rhizomes about 4 inches deep into a fine seedbed in the spring as soon as soils are workable. Use a spacing of 3 feet between rows and between plants (about 4,850 rhizomes per acre). Expect that not all rhizomes will sprout. Field skips will require replanting in years two or three.
NITROGEN NEEDS. Giant Miscanthus appears to be remarkably efficient at capturing and retaining nitrogen. In European trials, nitrogen fertilization has had no significant effect on yield. Anecdotally, an ornamental planting in central Illinois has grown 18 years without being fertilized and continues to reach 12 to 14 feet tall and produce numerous stems.
However, Voigt said, more fertility research in Illinois is needed and is ongoing.
WATER NEEDS. Normally, the summer rains and humidity in Illinois, along with the state?s moisture-retentive soils, are adequate to produce high yields. Yield usually increases as more water is available to the crop, although Giant Miscanthus will not withstand continuously waterlogged soil.
WEED/INSECT CONTROL. Weeds must be controlled during the planting season to ensure a successful planting. However, to date there have been no biomass losses due to insects or diseases.
THE GROWING SEASON. The Giant Miscanthus growing season in central Illinois begins in late April and is completed as the plants go dormant after the first killing frost, usually in October. In central Illinois, established plants typically reach more than 6 feet tall by the end of May and greater than 12 feet at the end of each growing season. Established plantings develop about five to 10 shoots per square foot.
EQUIPMENT ISSUES. In the United States, no commercially available mechanical planters or harvesters are currently designed to work specifically with Giant Miscanthus rhizomes. In Europe, however, producers have successfully modified potato planters and harvesters for Giant Miscanthus. In addition, a British company has developed a mechanical planter for the crop. Stems have been harvested with hay cutters and balers.
YIELD PROSPECTS. Maximum yields should be obtained within three years on fertile soils, but may require four to five years on poor soils. In replicated U of I studies, the biomass yields of unfertilized Giant Miscanthus (planted in 2002) averaged 9.8 tons per acre in northern Illinois from 2004 through 2006, 15.5 tons per acre in central Illinois and 15.8 tons per acre in southern Illinois. This far exceeds unfertilized upland switchgrass, which had biomass yields ranging from 2.2 to 5.2 tons per acre in Illinois.
- 30 -