Traders regard the supply and demand report as the gold standard for crop forecasts. Its release often roils Chicago Board of Trade grain and soy futures and sets price direction. Farmers rely on the data when planning for planting and harvesting.
"This all just adds to uncertainty," said Dan Basse, president of AgResource Co in Chicago. "Whether it's sales or Chinese demand or anything, we are shooting in the dark."
In November, the USDA lowered its 2018 yield estimates for the US corn and soybean crops, and Basse said traders expect further reductions in January.
Aside from US forecasts, the report includes USDA's latest fix on everything from corn and soy production in major exporters Brazil and Argentina to projected wheat exports from top suppliers such as Russia, the European Union, Argentina and Australia.
Also delayed are a quarterly report on US grain stocks, a final US crop production report for 2018 and USDA's report on winter wheat seedings for harvest in 2019.
"Everybody needs a god, if you will, and in the grain world, the USDA tends to be that" for data and statistics, Basse said.
The shutdown was triggered last month by President Donald Trump's demand for $5 billion to fund a US-Mexico border wall. Democrats who now control the House of Representatives have vowed to fund the government through legislation, but Trump has insisted that any plan include money for the wall.
Trump and congressional leaders were to meet on Friday to discuss breaking the impasse. About one-quarter of the federal government, including many workers from USDA, are off the job.
Farmers already battered by the US-China trade war may also face delays in crucial aid and loan payments from the federal government because of the shutdown.
The government last year pledged up to $12 billion in aid, to help offset some of the losses for crops hit by retaliatory Chinese tariffs imposed in response to Washington's tariffs on Chinese goods. The deadline to apply for the aid is January 15, yet the USDA offices where farmers must submit their applications have been shuttered since December 28.
Secretary Perdue will determine if the deadline should be extended, according to a statement USDA's Farm Service Agency sent out on Friday.