Hiroshima Peace Memorial Park, built at what was once the hypocenter of an atomic blast, is the most visible sign of the city's renaissance as a force for peace in 21st century politics. But it is not the only reminder of the spirit of Hiroshima. Less well-known are the scores of "survivors" dotting the metropolitan landscape. These treasured trees, shrubs, and groves date from before the bombing on August 6th 1945. They were spared from annihilation,...