"Baltimore’s seaport is a world of big, noisy steel machines: Giant cargo ships, cranes, and roaring trucks.
In the middle of this hubbub, David Ng, a U.S. Customs and Border Protection officer, tries to find things that are small and alive: Snails, moths, and weed seeds of all sorts.
It’s part of a long-running struggle to protect America’s fields and forests from exotic insects and weeds. That struggle plays out every day in seaports and airports across the country. There have been many failures in that struggle, but a few weeks ago, the inspectors also experienced a small victory."