Barking dogs. Untrimmed trees. Loud back-yard barbecues. Poor parking etiquette.

On the surface, such nuisances sound minor. But they can trigger unrest in even the most idyllic neighborhoods, especially when people haven’t gotten to know each other.

Last week, in a chilling case, a yearslong fight over deer feeding exploded in bloodshed between New Brighton neighbors. While only a tiny number of disputes turn deadly, it’s not uncommon for them to escalate to open hostility, say police and mediators.

Though Minneapolis and St. Paul police say they get many neighbor-feud calls, they do not break them out as a category. But many suburban cities and counties do, and the numbers speak to their frequency.

In Coon Rapids, police responded to 120 neighbor dispute calls last year and 24 so far this year. Blaine police took 121 such calls last year and 28 this year. Minnetonka police logged 67 such calls in 2013.

The Anoka County Sheriff’s Office responded to 89 calls in 2013 and 31 this year. The Ramsey County Sheriff’s Office, which provides police service for several northern suburbs, does not have a neighbor complaint call category, but deputies responded to 625 noise complaints, 112 code violation complaints, 227 parking complaints and more than 1,000 animal calls — all ingredients of neighbor disputes.

“People call us for all sorts of things,” said Coon Rapids Police Sgt. Thomas Hawley. “They call us over a property line dispute. They call because, ‘Their floodlight is shining into my bedroom!’ ‘They’ve put their fence on my lot line!’ ‘They’ve cut branches on my tree!’ ‘They planted their flowers in my yard!’

“It seems like a lot of people are not comfortable going over and talking to their neighbors politely,” he said. “They call 911 instead. … You get there and oftentimes all you can do is keep the peace.”

Often to the callers’ distress, there’s not much police can do when a neighbor’s dog poops on the lot line or someone plows snow into a yard. Such actions simply don’t rise to the level of criminal behavior.

Officers listen calmly and try to get the parties to talk to one another. “That’s the frustrating part to us — just being in the middle,” said Minnetonka Police Chief Mark Raquet.

Crossing the line

It’s unusual for such feuds to cross the line into threats or violence. But it happens.

“We’ve had assaults that occurred over neighbor disputes,” said Ramsey Police Chief James Way. “Someone’s son or daughter drives by their house too fast. They confront the person themselves, and there is pushing and shoveling. … Neighbors do get into it over any number of issues.”

Very rarely, feuds escalate in shocking ways.

On Monday, Neal and Paula Zumberge of New Brighton were charged in the shooting death of neighbor Todd Stevens and the wounding of Jennifer Clevens, the culmination of a feud over Stevens’ and Clevens’ deer-feeding — which is not illegal in New Brighton.

Last year, White Bear Lake resident Lori Christensen was dubbed the “Neighbor from Hell” and sentenced to five years’ probation after a feud resulted in a restraining order that Christensen violated.

In 1996, Paul Craw­ford, 72, killed a family of four that lived by him near Sauk Centre, Minn., then killed himself. He was angry because the children had played on his dock and he suspected the family of removing a surveyor’s stake.

In 1991, Minnetonka homeowner Donald Brown shot and killed neighbor Robert Percival over his messy yard. Then he called City Hall to ask: “Now that Robert Percival has left this mortal existence, when is that property going to be cleaned up?” Brown was convicted of manslaughter.

The peacemakers

In many cities, police refer feuding neighbors to mediation services.

Ramsey, Coon Rapids, Fridley, Blaine and many other north-suburban police departments and Anoka County send them to Mediation Services for Anoka County, which handles neighbor disputes for free. It’s one of seven nonprofits certified by the state Supreme Court to resolve feuds outside of court.

Dave Bartholomay, executive director of Mediation Services for Anoka County, said last year, his nonprofit handled 228 mediations, dozens involving neighbors. “We see a lot of neighbor cases where you worry if we don’t get them in and help them resolve it, where will this end up?” he said. “It’s a wide range of slights that grow and grow. ... It becomes an unhealthy kind of obsession.” The longer a dispute festers, the more potentially dangerous it can become, he said.

When a dispute is referred to Anoka County Mediation, both parties must agree to mediation. Both sides tell their side of the story uninterrupted to a neutral mediator. A resolution is signed by both parties, but it’s not legally binding.

In one case, he said, older neighbors repeatedly had called police about a young man’s bonfire parties. During mediation, the man agreed to take the party inside at 11 p.m. and the neighbors agreed to stop calling police.

“It doesn’t have to be all kumbaya and skipping off together in the sunset, but it’s figuring out how to be a good neighbor,” said Jeanne Zimmer, executive director of Dispute Resolution Center, the nonprofit serving Ramsey, Dakota and Washington counties.

Dispute Resolution Center, which uses a sliding fee scale, handles 200 to 1,000 cases yearly. The first hurdle is convincing people they don’t need a legal hammer to get results.

Cultural and value differences can play a role in neighbor disputes. Zimmer recalled a dispute between a gay couple and straight couple. The neighbors had defined the rift as being about parking and noise, but later revealed some underlying judgments about lifestyle.

“You can still be a good neighbor even if you have very different ways of seeing the world,” she said.

Estranged strangers

Disputes tend to surge in the summer months, said Beth Bailey, executive director of Community Mediation & Restorative Services in New Hope, which serves 40 suburban cities in Hennepin County. Her organization has contracts with its cities and does not charge neighbors.

Bailey said another key factor is that people are less likely to know their neighbors now.

“We pull into our garage and close it behind us,” she said. “We tend to not interact with our neighbors. People are more inclined to call the police if they don’t know anything about their neighbors.”