Ethanol plants buy corn in huge quantities on advance contracts, meaning farmers agree on a price a year or more before the harvest season. They are assured of a buyer but they could also end up getting less for their corn than the current market rate.

That’s something Brian Hager, a Mankato, Minn., farmer, said he’s unwilling to risk. When the price is right, he said, he trucks his corn 60 miles north to an elevator in Savage, Minn., site of a barge dock served by Upper River Services. He’d rather wait to see what the foreign markets will bear.

Farmers like Hager keep big barge companies Ingram, Cargill and American Commercial in business. They are able to move bulk goods on the river far cheaper than their competitors can by truck, rail or air freight.

Ingram, the largest operator, maintains 4,000 barges. Jerry Knapper, an assistant vice president, said that in addition to grain, coal is among the prize cargos.

An estimated 180 million tons of coal are shipped annually on the Mississippi River and its tributaries, said Knapper. That’s enough coal to satisfy the energy needs of a city the size of Chicago for several years.

Gasoline and other liquid petroleum products account for 200 million tons of shipping annually on the Mississippi, government records show.

Oil refineries are located all along the river, but they’re heavily concentrated in Louisiana between New Orleans and the offshore drilling platforms that pump crude oil from the Gulf.

Still, the Mississippi is not strictly business. Tourist and pleasure boats mix with towboats and barges. No city-to-city passenger boats, though. They vanished with the end of the steamboat era in the mid-19th century. Now, only a few true steamers work the river as tourist attractions.

More common are excursion boats such as the diesel-engine-powered Memphis Queen III sternwheeler owned and operated by Captain Lozier. They are heavy on charm and memory of the river’s rambunctious past, holding up to 400 people for day cruises, weddings, dinner parties and other special events.

Lozier, whose grandfather built the three-deck, 110-foot Memphis Queen III, sells $20 tickets for an afternoon on the river. For that, you get a nostalgic trip through the heyday of cotton, cutthroat commerce, frontier preachers and a westward looking America.

You also learn that Samuel Clemens took his pen name Mark Twain from a term used by riverboaters to measure the Mississippi’s depth. They would drop a chain in the water, reckon how long until it hit bottom and then call out the depth as “mark three” or “mark four” and so on. Each mark meant a fathom or six feet. “Mark Twain,” legend goes, was two fathoms.

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