CHARLES CITY -- Art Schmitt has seen the Shell Rock River rise over its banks three times in 31 years of farming near Rockford.

Nothing like this year, though. Flooding has washed away about three acres of corn, leaving a huge black scar and limestone rocks.

Meanwhile, near New Haven in Mitchell County, a fen (marsh) and man-made wetland filter nitrates and herbicides from rainwater as part of a Conservation Reserve Enhancement Program project on John Kirst's Century Farm.

It presented quite a contrast for state officials who toured the area Tuesday.

"We wanted to show the effects of severe soil erosion" to legislators, said State Rep. Mark Kuhn, D-Charles City. "But then we wanted to show what a change in tillage practices could do to keep the soil and the land.

"Maybe this will be enough of an incentive to get people to invest more in long-term flood control. Because what starts as excess rain in a farm field often finds its way to nearby towns and swollen rivers and goes on downstream," Kuhn said.

The tour began near Rockford, where Schmitt and his brothers farm 160 acres of corn and soybeans.

If he knew another major flood was coming, Schmitt said, he might idle the land.

"But it is good ground and it has fed a lot of people over the years," he said. "I'd hate to take it out of production. I'd like to try farming it again. If it doesn't work, it doesn't work."

Kuhn, Iowa Secretary of Agriculture Bill Northey and others also discussed possibilities of terracing farmland in the Washington School Watershed near Charles City -- and saw fields devastated by flooding north of the city.

The Kirst site is one of the first CREP wetlands in Mitchell County, said Charlie Kiepe, a CREP specialist with the Iowa Drainage District Association.

Water that leaves the wetland is mostly free of nitrates.

"It's a start," Kiepe said, "and it does make a difference. It's the right direction."

A total of $36.95 million was provided by the Iowa Department of Agriculture and Land Stewardship in the past year for conservation and was matched by almost $20 million of landowner investment, according to the department.

"We think there are some answers out there," Kuhn said, "and we just continue to work together and provide some voluntary incentive programs to landowners. We can do some good things.

"We're going to have to work together with the federal government to assist landowners to get it back to the way it was," he said.

Contact Dick Johnson

at dick.johnson@globegazette.com.