A near-record harvest, low crop prices and a shortage of storage space are changing the way some farmers store their crops.

Across Minnesota and elsewhere, many growers are stuffing corn, wheat and sometimes soybeans into 300-foot polyethylene bags, 10 feet in diameter.

The process, called grain bagging, provides temporary storage in farm fields that eliminates the need to wait in line to deliver grain at elevators, or possibly dump crops on the ground. And in a year when corn prices have hit five-year lows, bagging allows farmers to postpone selling their crops to see if prices will turn around.

A specialized agricultural equipment company in central Minnesota has noticed the change. Loftness Manufacturing, based in Hector, was the first company in the U.S. to begin making grain-bagging machines in 2008. Its business, especially in Minnesota, the Dakotas, and Canada, has skyrocketed.

"We've been on overtime since April and the way it looks now we'll be into November — Thanksgiving probably — before we're back to normal schedule," said Loftness' co-owner and chief financial officer, Gloria Nelson. "The products are all sold before they leave us."

Driving the demand is a combination of factors: bumper crops, low prices, and grain elevators that in some cases are still holding 2013 crops because of a rail backlog.

"There's nowhere for this crop to go," said Marc Van Buren, a sales representative for Lange Ag Systems in Willmar, which sells the Loftness equipment.

Some producers in recent years have invested profits in new steel grain bins and grain dryers as a more permanent way to increase on-farm storage.

But others have been attracted to bagging as a less expensive alternative that allows them to harvest crops more quickly.

Tom Milbrandt, a farmer who grows corn and soybeans with his sons on about 3,000 acres near Marietta on the Minnesota-South Dakota border, said he uses about 15 to 20 bags per year.

Bagging allows him to harvest up to 250 acres per day with two combines and three people, he said.

The alternative, loading grain onto trucks and hauling it to grain elevators, takes twice as long and requires five workers, Milbrandt said.

"What I detest most is setting in line at an elevator," he said. "In the fall you can sit there for an hour at a time to dump a load, and it's just the most unproductive time."

And if grain elevators are full, Milbrandt said, farmers need to pay "cash price" as they deliver their corn. "Harvest time is usually the lowest price for grain," he said. Milbrandt said he removes the corn from the bags and trucks them to grain elevators in December or January when prices are higher.

Milbrandt said that more farmers near him are starting to use grain bagging, and one grower had 60 bags in his field last year.

Bagging corn in the field is a fairly simple process. Grain carts or combines unload corn into a hopper hooked to a tractor, and an auger pushes it into a bag that's sealed at one end.

Pressure from the bag as it fills pushes the hopper and tractor forward as the bag unfolds across the field. It is then sealed at the other end. Loftness officials said a 300-foot bag can be filled in 30 minutes if it has a constant supply of grain.

A 10-foot grain bag loader costs about $28,500, and an unloading machine costs about $40,000. Bags cost about $975 each.

The company also makes a 12-foot diameter model that fills a 500-foot bag.

Loftness is a 100-person firm that also makes other specialized equipment, but grain bagging has become its "flagship product," said vice president of sales Jerry Sechler. The firm has sold more than 3,000 grain bag loaders and unloaders since 2008 in the U.S. and Canada, he said.

Cost-saving option

Bob Zelenka, executive director of the Minnesota Grain and Feed Association, said he doesn't blame farmers for choosing bagging as a less expensive option than elevators or other "fixed storage," especially when elevator and bin space is short. "They're trying to avoid having to store it in the elevator under a warehouse receipt where it can cost 3 cents to 4 cents per bushel per month to store it," Zelenka said.

Some elevators have also experimented with bagging grain, he said, but chose not to continue.

"They found that it was a little difficult maintaining the quality of the grain when it's in a bag like that in terms of moisture and mold," Zelenka said.

He warned that grain put in bags, like grain put in steel bins, can't be too wet or it could spoil.

But Dave Nelson, Loftness senior vice president of sales, said if the bags are properly filled and sealed, there's minimal oxygen and little chance of spoilage.

There can be problems with raccoons or squirrels breaking into the bags, Nelson said, but those can largely be avoided if growers don't load the bags too close to wooded areas and use traps or other precautions to discourage scavengers.

State pollution control officials have noticed the increased use of plastic bags on farms, including thousands that are already used at dairy operations to store corn silage fed to cows.

Like the silage bags, grain bags cannot be reused or recycled.

Wayne Gjerde, recycling market development coordinator at the Minnesota Pollution Control Agency, said that he has been working for years to get companies interested in recycling the large farm bags, and so far there are no options.

But Gjerde said an Arkansas firm is doing a pilot program to recycle the bags into plastic irrigation pipe and agricultural films. He's hopeful that some markets may begin to emerge in the next couple of years.

In the meantime, said Heidi Kroening, MPCA supervisor of compliance and enforcement for solid waste, farmers must follow the law and dispose of the bags in landfills.

"The bottom line is you can't burn this stuff," she said.

Tom Meersman • 612-673-7388