The U.S. should consider diversifying ag export markets as one of its primary importers of soybeans, corn, beef and pork — China — sees its demographics change and priorities shift, creating an increasingly unsettled and potentially volatile trade relationship.

Wells Fargo’s Agri-Food Institute, which conducted an analysis of U.S.-China relations, presented an outlook last month on the future of trade with China — the world’s largest agricultural import market and one of the  principal U.S. trade partners.

Courtney Buerger Schmidt and Lon Swanson, sector managers, said longer term the U.S. needs to work toward expanding its trade footprint into other high-growth...