Although slow to propagate,this crop offers high yields. Giant miscanthus is an impressive, 11'-tall grass that produces 10-16 dry tons/acre from stands that can last up to 15 years. Yet it's a sterile plant; its rhizomes need to be dug up, divided and replanted.
“It's a slow process to build up any large acreages of it,” says Tom Voigt, an extension agronomist with the University of Illinois, which has been studying miscanthus as a possible biomass crop for about eight years.
“It would be safe to say that we might be five or more years away from this becoming a commercial reality. That said, there's still a tremendous amount of interest in the plant, and we haven't been discouraged by how slow it is to propagate.
“We get a lot of calls. I spent this morning with a farmer who is thinking of growing biomass. He's got some connections with one of the energy companies and they've put him in touch with us to talk about growing miscanthus.”
Voigt gets a lot of requests for rhizomes, but no commercial outlet in the U.S. is producing them, he says.
Ceres, Inc., a new biomass seed company that just released switchgrass and sorghum varieties under the Blade Energy Crops brand, is looking into miscanthus, says Anna Rath, its vice president of commercial development.
“We don't believe the grower economics will work for it yet, which is why we haven't brought our miscan-thus to market yet. We are working on improving the crop to overcome those economic disadvantages. Once we succeed, we do plan to bring miscanthus to market,” Rath says.
At this point, about 50 acres of the crop are planned for planting this year at the university's energy farm. “We have some pretty rudimentary planters where we can plant an acre an hour,” Voigt says. “And there are other breakthroughs in other pieces of equipment that we think will improve our success.”
In plots in central Illinois, yields are 14-16 tons/acre. For large-scale production, Voigt expects to see yields more in the 10- to 14-ton/acre range from central and southern Illinois.
Besides the labor involved in planting rhizomes, Voigt voices another concern. “We're dealing with a clone. We haven't seen any commercial pest problems, but we have limited acres of this plant.”
If attacked, whole stands could be wiped out, he suggests. At the same time, the Europeans have been growing miscanthus commercially for heat and electricity since the early 1990s and haven't had any specific problems, he adds.