Land dispute lawsuits have involved a number of high-profile litigants — from Martha Stewart to Mark Zuckerberg. (Video: TWP)

Riding lawn mowers are still popular, and, yes, most of them are driven by older men. The object of all their smoke and noise may be a manicured lawn, but the process clings tightly to the American ideals of power, control, self-sufficiency and freedom.

In the 21st century, the last place a red-blooded man can be a cowboy is on the suburban lawn, riding his steed across the plains to round up his herd of grass. The lawn tractor “is the American Dream,” said Jon Traunfeld, director of the University of Maryland’s Home and Garden Information Center.

No wonder, then, that the libertarian-minded junior senator from Kentucky, Rand Paul, would live in a place named Bowling Green and that his time away from Washington would include a lawn-clipping detail astride his riding mower.

Lawn mowing, it should be said, is also a great Zen experience, a way to unclutter the mind, especially if you wear ear protectors, as the senator reportedly does. What should have been a blissful blend of self-determination and mindfulness, however, ended badly for Paul on Friday when he was apparently tackled by his neighbor, Rene Boucher. Paul, 54, suffered five broken ribs and bruised lungs. Boucher, 59, has been charged with assault.

On the surface, the whole incident seems bizarre. I can’t be alone in finding it hard to even summon the idea of a U.S. lawmaker on a lawn tractor. Folksy Paul Ryan, perhaps, but Mitch McConnell?

No doubt the full story of the attack will come out in court, but we already have a glimpse of the dynamics. The neighbors haven’t gotten along in years. Some of the reported sources of the dispute had to do with recently planted trees, grass clippings that strayed, and leaves left unraked. Such disputes are familiar to homeowners across the land, particularly in that strange limbo between city and country we call suburbia, a place where territorial aspirations so easily exceed their boundaries.

Such extreme neighbor conflicts as assault are usually the culmination of long periods of tension. Paul and Boucher have lived next to each other in their gated community for 17 years. But yards are battlegrounds; they’re where boundaries meet and outlooks and personalities collide.

Traunfeld and other horticulture pros who advise homeowners have spent years encountering such disputes.

In my travels, a common gripe is that a neighbor’s tree has brought unwanted shade. Some of the concerns are more pressing — a neighbor’s decaying tree overhanging one’s house, floodwater that causes erosion and property damage, unchecked invasive weeds, junk that becomes a breeding ground for mosquitoes. But others are less rational. No, your neighbor isn’t really responsible for leaves carried by the wind from her tree to your gutter.

Autumn leaves in general are a source of great vexation, particularly when you add the relatively recent invention of the leaf blower. This is a machine that to some is indispensable in yard grooming; to others, it’s a major source of neighborhood pollution, with noise, fumes and dust.

We know you love your leaf blower, but it’s ruining the neighborhood

Leaves have the capacity to irritate some neighbors if they are left untouched, and they irritate others when they are blown. Traunfeld scratches his head when he sees neighbors blow leaves and grass clippings from their properties onto the street, where they simply sit over the winter, rotting and clogging storm drains. Once the leaves are off the property, “they feel it’s not theirs anymore, and that’s ridiculous.”

Another source of conflict arises from widely different perceptions of what is unkempt and what is not. Some people are obsessive about lawn mowing and edging and removing any fallen leaf. This contrasts with a movement in gardening toward more naturalistic gardens that are often read as being weedy.

Animals — both pets and wildlife — present another enormous well of poisoned relations. Adria Bordas, horticultural extension agent for Fairfax County, Va., recalls the case of a resident whose new, expensive plantings were being eaten by deer because a neighbor down the street was maintaining a smorgasbord for wildlife.

Irritation morphs into enmity when one neighbor perceives an action as not just careless but also willful, as when someone blows their leaves onto the neighbor’s lawn on purpose. Even more extreme: accusations of plant poisoning. This is not an entirely unfounded fear.

“I have had people ask me if I would take soil samples for them so I could testify in court,” Bordas said. She stays out of such disputes, but there are consulting arborists who do that kind of work.

“It can get very heated, and it’s amazing some of the stories people share,” she said. “Some people plant certain things on a certain side of the property, plants that stink.”

Traunfeld and Bordas advise people to make the effort to get to know their neighbors so that when the inevitable problem arises, there’s a rapport that will smooth the wrinkles.

That isn’t always possible, Bordas concedes. “The days of leaning over the fence with an apple pie are gone,” she said, laughing.

One of the oddest recent cases of neighborhood confrontations occurred this year in England when a man described as “a rampaging pensioner” attacked his neighbor’s home with a hammer while wearing a false beard. The disguise did not fool the law, and he was duly convicted and fined.

And if you see your neighbor on a lawn tractor with ear protectors on, it’s probably best to leave him be.

Nan Fairbrother, writing in her 1956 book “Men and Gardens,” observed that because “human beings are gregarious creatures, there are many things we share quite happily with our neighbors. But gardens are not one of them.”

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