Harvest season is in high gear, and U.S. farmers have another supply chain challenge. Bloomberg says there aren’t enough barges moving goods up and down the shrinking Mississippi River. Drought is drying a vital American waterway, which means a lot less room for vessels moving corn and soybeans from farms to U.S. ports. At one point last week, barge rates hit $49.88 per ton. That’s the highest price on record and a 50 percent jump from 2021 shipping rates. More than half of the corn and soybean shipments heading to world markets travel along the Mississippi. The barge problems are hitting at harvest when the supplies of grain will be at their largest. It also follows a challenging growing season filled with weather problems and soaring inflation for things like fuel and fertilizer. Fertilizers needed by producers to grow grain are also at risk as they ship along the Mississippi.