CEDAR RAPIDS (AP) – The farming landscape changes relentlessly in Iowa.

There are fewer and larger farms, bigger machines, fewer livestock operations, fewer fences.

Fewer fences?

Curt Zingula, who farms 1,460 acres between Marion and Central City in Linn County, estimates that more than half the farm fence in the county has come down since he began farming in 1976. Then, he was farming 120 acres divided into seven fields. It’s all one field now, said Zingula, president of the Linn County Farm Bureau.

Michael Duffy, Iowa State University agricultural economics professor and director of the school’s Beginning Farmer Center and graduate program in sustainable agriculture, said he’s not seen any research that quantifies the disappearance of farm fence in Iowa. He only knows some of it has vanished and for one central reason: ”We are losing cows.”

The number of farm operations in Iowa with beef cows has dropped from 38,000 in 1986 to 21,000 in 2007, he said. In 1980, the state had 14,000 dairy farms; it has 2,400 today, he adds.

As farmers age and as fewer young people go into farming, ”the first thing that goes is the animals,” Duffy said.

He said bigger farms, with bigger equipment to maneuver and without livestock to fence in, can make ripping out farm fence an attractive option.

Zingula said the majority of farmers take pride in keeping their farm and the land they lease to farm as attractive as possible. Unneeded fence, he said, takes effort and money to maintain and can make a place look ugly when it isn’t.

”Once it gets old and rundown and rusty, a lot of us consider it to be an eyesore,” he said, ”and you might as well take it out.”

Zingula said he also has removed fence along the road to lessen the drifting of snow in winter.

Removing a fence, he said, can give a farmer two more rows of crop where the fence had been, but the real economic bonus is not having the cost and effort of spraying weeds and killing the trees that grow in the fence row, he said.

In Iowa, it falls to township trustees to arbitrate fence disputes, and Zingula has been a Maine Township trustee since 1992. The dispute procedure is a formal one and costs a farmer to pursue a dispute resolution. In his 18 years as trustee, there have been disputes in Zingula’s township, but none in which a farmer wanted to pay to have it formally resolved.

In most cases, Iowa law requires farmers on both sides of a fence to take responsibility for half in something called the ”right-hand rule.” Each farmer stands in the middle of a fence row, and each is responsible for the portion of the fence to the right.

This means a farmer whose neighbor has cattle must maintain half the fence, even if he doesn’t have livestock and doesn’t intend to have livestock. That can make for disputes, said Zingula.

Farmers also dislike the idea, he said, of having to maintain a fence they share with a hobby farmer with a couple of cows.

Often neighbors do share a desire to take down a fence, which is the case with Zingula and new neighbor Hertz Farm Management Inc. in Mount Vernon.

Kirk Weih, an accredited farm manager with Hertz, said removing fence will ”shine up the farm” and provide better accessibility for farm machinery.

After the crops are harvested in the fall, Zingula and Weih will hire a contractor and split the cost to rip out three-eighths mile of fencing.

It’s another small part, said ISU’s Duffy, of something larger in the Iowa countryside.

”The whole vista has changed,” he said.