Humans often use flowers as decorative accessories. But in this book, Stephen Buchmann, a professor of ecology at the University of Arizona, explains that they also serve other, more urgent purposes. Pollen traces, for example, are used to catch criminals. Chamomile and African marigold flowers are used to treat insomnia and skin infections, respectively. The flower business accounts for more than 5% of the Netherlands’ GDP. And in Colombia, which provides 70% of the flowers that U.S. consumers buy, the industry employs at least 111,000 people. Of course, the most important reason for flowers is more straightforward: “Their fruits and seeds keep the world’s 7.2 billion people from starvation,” Buchmann writes.
This appears in the July 20, 2015 issue of TIME.