Some U.S. railroads will start halting crop shipments on Thursday, a day ahead of a potential work stoppage, an agricultural association and sources at two grain cooperatives said yesterday, threatening exports and feed deliveries for livestock, Reuters reported. With farmers starting to harvest autumn crops that are shipped to meat and biofuels producers, the shipping disruptions could add to already high inflation. Farmers also plan to add fertilizer to fields after the harvest, and shipments of fertilizer are being delayed. Max Fisher, chief economist at the National Grain and Feed Association, which represents most U.S. grain handlers, said that rail customers reported at least one railway would stop taking grain shipments on Thursday morning. Most major U.S. railways have already stopped accepting new shipments of ammonia fertilizer and other potentially hazardous materials, said Justin Louchheim, senior government affairs director at The Fertilizer Institute, an industry group. Louchheim said fertilizer producers are now evaluating how much storage they have for ammonia that cannot move by rail, and whether some can move by truck. The potential rail shutdown looms just six weeks before most Midwest farmers would begin applying fertilizer, said Josh Linville, fertilizer director at StoneX Group. About 40% of the U.S. fertilizer supply is on a rail car at some point before arriving on a farm, he said.