Some biomass energy crops make sense environmentally and economically. For example, poplar trees are farmed sustainably to yield energy harvests every 3 to 6 years. Poplar requires less water and other inputs than crops such as corn. After harvest, the tree re-sprouts from the same root stalk, a very efficient way to produce biomass.
Especially on marginal lands, energy crops that are not deemed invasive and do not require water may be an economical and a productive use of the ground to produce biofuel feedstock for torrefaction.