According to data from IHS Markit, almost 7 percent of the U.S. container trade with China is at risk and 3.1 percent of containerized U.S. exports have already been impacted by the first round of tariffs that went into effect.
The U.S. ports most exposed to the U.S.-China trade duties based on overall goods targeted are Los Angeles and Long Beach, California with 25 percent market share apiece followed by the New York-New Jersey port complex, Savannah, Georgia and Wilmington, N.C., according to IHS Markit data.
"China is our number one trading partner — 70 percent of our goods come from or go to there," said Eric Bradley, a spokesman for the Port of Long Beach. "Broadly speaking, China accounts for about two-thirds of our imports, and it's the destination for about one-third of our exports."
The top agricultural commodities shipped out of the Los Angeles/Long Beach port complex to China include oilseeds such as soybeans, various grains, nuts, fruits, dairy products and meats, based on IHS Markit data.
Also, the Port of Oakland has seen its agricultural exports rise more than 40 percent in the past four years and leading export commodities last year included California almonds and rice. The port also has been undergoing a big expansion of its refrigeration capacity to attract more food shipping business.
"We have seen no impacts yet from the trade situation," said Mike Zampa, a spokesman for the Port of Oakland. He said January and February exports from the port were up from a year ago, but March export volumes due to be reported this week will be flat largely as a result of other China challenges, including Beijing restricting exports of U.S. recycled materials.
A good portion of California's wine also gets shipped out of the Oakland port complex, which is close to the state's Napa Valley wine region. Hong Kong was a stronger market for U.S. wine sales last year than mainland China.
Oakland also handles some soybean exports as do other U.S. West Coast ports, including in Seattle-Tacoma marine complexes in the Pacific Northwest region.
China buys roughly half of the U.S. soybean exports, or about $14 billion annually, although the tariffs announced by Beijing have so far been just a threat and have not actually been formally implemented.
One commodity already impacted by the Chinese tariffs is American pork, with Iowa, Illinois and Minnesota the top three producing states. One in 4 hogs in the U.S. is sold overseas, and the Chinese are the world's top consumers of pork. At about $1.1 billion, mainland China and Hong Kong together are the third-largest market for U.S. pork based on value after Mexico and Japan.
Last year, the West Coast ports were responsible for more than $3 billion in exports of pork and the East Coast ports more than $1 billion, according to the National Pork Producers Council. The Great Lakes ports accounted for more than $570 million followed by the Gulf ports with nearly $180 million.
About 15 percent of the general cargo exports from the Port of New Orleans in 2016 were animal or vegetation products.
"At this time, it is unclear how a decline in China trade will impact Port NOLA's volumes, however, it would likely lead to losses in revenues in our import and export markets," said Donnell Jackson, a spokesman for the New Orleans complex. "There is still much uncertainty surrounding tariffs announced by the U.S. and now by China. We will continue to monitor developments as they unfold."