OAK RIDGE, Tennessee, April 29 -- The U.S. Department of Energy's Oak Ridge National Laboratory issued the following news release: * * * Microbes at the root of resilient energy crops How do you put a tree in a petri dish -- and, more importantly, why would you do that? For researchers at the Department of Energy's Oak Ridge National Laboratory, the answer lies in the intricate networks of bacteria and fungi hidden in the roots of towering Populus trees. These unseen communities shape plant  more