Expectations for a breakthrough were not high last week after top U.S. trade officials traveled to China to find a way to ease trade tensions between the two countries.

And even if the negotiators can reach a compromise, farmers in Iowa and around the Midwest may ultimately see a reduction in Chinese demand for soybeans, pork, beef, ethanol and other ag products, an Iowa State University (ISU) economist said.

The threat of trade tariffs is prompting Chinese importers to look beyond the United States for more of their ag imports, according to Wendong Zhang, an ISU Extension economist. “I fear that in many ways the harm has already been done even if the tariffs don’t come into play,” he said. “The trade tensions have really rattled the Chinese buyers. If...