When Lothar Determann first moved from Germany to California, he recalled looking forward to experiencing the redwood trees and other local flora of the Golden State. But during his first hikes, he was soon confronted with the fact that the Californian plant life was not only different—but that all the names were foreign, too.

Fast-forward to an unpleasant experience with poison oak and it was clear Determann needed to turn to one of the many nature field guides on the market. And soon, it also became clear that field guides would be helpful in other areas of Determann’s life.