While most of America is booming, family farms are struggling.

The median household income for farm owner-operators will fall for the fourth consecutive year in 2018, according to U.S. Department of Agriculture data. That’s partly a result of weak prices for agricultural commodities: The majority of such farms lose money on their produce and only make it up thanks to income from off-farm work, investments and government benefits. Still, the trade war with China isn’t helping any.

Stocks of soybeans inspected for export to China at U.S. ports came to about 339,000 metric tons in the current marketing year, down 97 percent from a year earlier. Yellow beans in Louisiana traded at $327.50 a metric ton on Monday, close to 25 percent below the $408.25 a ton at Brazil’s Paranagua port – a discount that neatly matches the 25 percent import tariff imposed by China since July. With grain storage space already at capacity, farmers are clearing hardier, cheaper corn inventories out of their elevators to make space for the bumper soybean crop being brought in from the fields – or even just dumping the new season’s harvest on the ground.

That’s an early warning sign of the ructions the rural economy will suffer if the trade tensions go on much longer.

The reason soybeans have overtaken corn as the largest U.S. crop in terms of planted acreage is only partly because of Chinese demand for soybean-meal animal feed and soya cooking oil. It’s also a result of better margins.

An acre of farmland in Illinois makes about $270 of income a year net of costs if planted with soybeans in rotation with corn. Because of the significantly higher amounts of fertilizer needed for cereal crops, corn planted after corn makes about a third less than that. Wheat is worse, and barely breaks even: The only way to make more than a few dollars from an acre is to plant out the post-harvest stubble with a second crop of, you guessed it, soybeans.

The better income to be made from such oilseed crops, along with a decade of low interest rates, have encouraged farmers to lever up. Farm debt has doubled since 2006 and is forecast to top $400 billion this year. Farmers’ debt service ratios – the share of gross income needed to meet interest payments – will rise for the fifth consecutive year and hit a 30-year high of 28 percent in 2018, according to the Agriculture Department. If income gets squeezed more by weakness in soybean prices or a switch toward less trade-hit crops such as corn, those ratios will only get worse.

For the moment, voters in the U.S. grain belt seem fiercely loyal to President Donald Trump ahead of the country’s midterm elections, as Isis Almeida and Mario Parker of Bloomberg News reported Monday. It no doubt helps that President Trump has promised a $12 billion assistance package to the sector – so-called “unearned income” such as government benefits, pension payments, and returns on investments make up about a quarter of earnings for the median farm.

Still, falling revenues and rising debt have always been the death of businesses, and farms are little different: 468 of them filed for Chapter 12 bankruptcy in the 12 months through September. A food sector that tries to make do without feeding China’s voracious appetites won’t prosper for long.

To contact the author of this story: David Fickling at dfickling@bloomberg.net

To contact the editor responsible for this story: Matthew Brooker at mbrooker1@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

David Fickling is a Bloomberg Opinion columnist covering commodities, as well as industrial and consumer companies. He has been a reporter for Bloomberg News, Dow Jones, the Wall Street Journal, the Financial Times and the Guardian.

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