What is the significance of the title chapter?

Chapter Four speaks to the hope found in the items noted in the title. Hersey does not attempt to conceal the extent of the bomb's damage, very explicitly describing not only the physical injuries of people, but also the terrible state this once beautiful city is in. However, he does plant some seeds of optimism that serve as powerful symbols of hope for a city that has been torn apart. The most prominent of these are the sprouts of "panic grass and feverfew," the plants that give this chapter its name. Somehow, radiation from the bomb has stimulated growth, and shades of fuzzy green cover the bare Hiroshima ground as plants begin to appear. They are only a small solace, but they indicate that Hiroshima will be reborn.