In a word..maybe.

A final significant finding, Vogel says, is that yields on farms using fertilizer and other inputs, such as herbicides and diesel fuel for farm machinery, were as much as six times higher than yields on farms that used little or no fertilizer, herbicides, or other inputs to grow a mixture of native prairie grasses. That result contrasts sharply with a controversial study published just over a year ago in Science that suggested that a mixture of prairie grasses farmed with little fertilizer or other inputs would produce a higher net energy yield than ethanol produced from corn (Science, 8 December 2006, p. 1598). Instead, the current study--published online today in Proceedings of the National Academy of Sciences--shows that switchgrass farmed using conventional agricultural practices on less-than-prime cropland yields only slightly less ethanol per hectare on average than corn. "The bottom line is that low-input systems are not economically viable," Vogel says.