Construction has started on a cellulosic ethanol plant in Italy which will produce 13 million gallons of ethanol a year from Arundo Donax, a giant reed which can reach 30 feet in height and which is classified as invasive by California.
Much as we need alternative fuels, using amounts of crop land to grow plants for fuel rather than for food, is not environmentally sound, especially not when that plant is invasive.
Producing ethanol from plant, wood, and animal waste is certainly worthwhile. But using cropland to produce it, in addition to using large amounts of water and fertilizer, leads to high food prices as well as hunger in the Third World.