Port of Baltimore is a world of steel, big noisy machines: Giant cargo ships, cranes and trucks roaring.
Amid the hubbub, David Ng, an officer of Customs and Border Protection, try to find things that are small and live: Snails, moths, and weed seeds of all kinds.
It is part of a long struggle to protect the fields and forests of the United States of insects and exotic weeds. That struggle plays every day at ports and airports across the country. There have been many failures in that fight, but a few weeks ago, inspectors also experienced a small victory.
That day, David Ng opened the steel door of a shipping container to inspect a shipment of organic soybeans from China and saw a small feathery abroad. "It was just a little on top of the grain," he says.
It was a black and white moth, only half an inch long. Upon further inspection, Ng found a few more. "It was a moth we had seen before, or that I recognized any of the other inspectors recognized," he says.
He caught the bug, put it in a small glass vial, and sent out to experts in the U.S. Department of Agriculture.
Nemapogon gersimovi identified as a species of moth that had never been seen before in the U.S. He likes to feed on seeds and grains.
"This was a very important discovery," says Michael Raupp, an entomologist at the University of Maryland.
Over the years, Raupp says, dozens of pests have come here from abroad. He ticks off some of the most destructive: the cottony cushion scale; soybean aphids; European gypsy moth; European corn borer; the emerald ash borer.
Nobody knows exactly how much of a problem that the new moth China could have proved he says. But the latest invasive species have caused about $ 120 million in damage each year, "so I just do not need another one of these guys here."
CBP gave this soybean importer a choice: destroy beans or out of the country. Finally, soy China again.
Inspectors cannot possibly watch every incoming shipment. Focus on ships they believe are more likely to contain pests, based on past history.
On the morning of my arrival, I was a recipient of organic wheat Argentina.
David Ng snaps a plastic seal on the container with a bolt cutter and changes to open the steel door of the container. Some wheat is poured.
"Now we're going to kind of sift through it a bit," says Ng. "Let's see if we see something that stands out. Any movement or any other contaminant that pop out or look out of the ordinary."
Groove Amanda, another CBP officer pours samples of wheat on a set of sieves and shake the grain back and forth, stopping every few seconds to look carefully. Grab something carefully. This is not wheat. It is a seed oats family, which includes at least one species that the government considered a "noxious weed."
"Let's send this to a botanist, USDA, and they'll come back to us and let us know what species it is, and if any action is required," says Ng. They usually get a response within a few hours.
Nationally, CBP inspectors found hundreds of insect pests and weed seeds every day. Others probably slip through, but Raupp says it is not a wasted effort. Each successful detection is a small victory.
"It is vital," he says. "It's a good fight we have to keep fighting, I think."
Inspectors have indeed managed to keep some pests out of the country, as the voracious beetle Khapra. Border inspectors caught 200 of these insects each year. The Khapra beetle is found in Asia, Africa and the Middle East. But for the moment, not in the United States.
Regarding the shipment of Argentine wheat, which came through cleanly inspection. That seed of wild oats, there was nothing to worry about out. This container will leave the port and go to help meet the U.S. appetite for organic bread.