The Southern Dragon (The Songbird River Chronicles)

The stories of Singer and her friends continue three years later. Nothing will grow in the ruined Songbird River City, despite Singer's best efforts. What's worse, her energy dissipates every time she tries to use it lately. When Katherina arrives with news of Farien's disappearance and a mysterious jungle springing up to the south, both Singer and Katherina must embark on journeys to the far corners of the continent.