"Beginning in the late 1980s, a series of improbable bark beetle outbreaks unsettled iconic forests and communities across western North America. An insect the size of a rice kernel eventually killed more than 30 billion pine and spruce trees from Alaska to New Mexico. Often appearing in masses larger than schools of killer whales, the beetles engineered one of the world's greatest forest die-offs since the deforestation of Europe by peasants between...