WARREN – Much of this week’s furor over reconstruction of a 1.6-mile chunk of Route 1 has been focused on one thing: trees.

Some of the participants say the 18 stately trees that dominate the rolling road are “traffic calmers,” keeping people from speeding. Others call them “deadly fixed objects” that loom as hazards to the same drivers.

The contrast has been so sharp that at least 15 people chose to be hauled off to jail in the past week instead of accepting the start of what might be described as a run-of-the-mill road upgrade.

So far, protesters have not stopped the reconstruction. They have succeeded in getting noticed for one of the largest acts of civil disobedience in the state in recent memory.

What is at stake to generate such a response?

A rural way of life and the integrity of a neighborhood, the safety of homeowners, and the role of citizens in influencing public policy that directly affects them, opponents say.

Transportation Commissioner John Melrose admits to being at a loss in understanding the line protesters have drawn in the pavement.

For one thing, the highway labors under the demands of 9,000 vehicles a day.

And, while meetings with neighbors have not always gone well, the state Department of Transportation has scaled back the scope of the work and is even offering to tear up pavement later if the work proves to be a mistake, Melrose said.

Diana Sewall has lived on Route 1 since 1948 when her father built the family home. An amateur historian and genealogist – and descendant of Warren’s first settlers – she puts the debate in a context beyond traffic engineering and two-year transportation plans.

The house she lives in was built in 1876 and is just 39 feet from the road. Other houses on Route 1 date from the founding of the village in 1736 and predate any east-west road in the area. “I’ve got pictures of it in 1910, and it was just a little one-lane dirt road,” Sewall said.

“They’re ruining an old neighborhood for no good reason,” she said.

The only benefit she sees is for trucks heading north to Rockland’s industrial park, and trucks from Thomaston’s Dragon Cement plant traveling south to the Big Dig in Boston.

Like other opponents, she wonders why it is important to speed tourist traffic north to perennial summer traffic backups in Thomaston and Rockland.

Sewall was an opponent who did not get arrested. And being involved in a protest like Monday’s surprised her.

“I never thought I’d do anything like this in my life,” she said.

A protest leader, Steve Burke, 60, was arrested Monday. He has lived on Route 1 and operated a screen-printing business along it for 22 years. He dates his involvement in the widening issue to the early 1990s, when, he says, Rockland and Thomaston businesses lobbied DOT to widen Route 1 from the Route 90 intersection easterly to downtown Thomaston and Rockland.

DOT announced the project almost three years ago, calling for adding paved shoulders, or breakdown lanes, and set up a series of public meetings in Warren.

Opponents at those meetings felt they had communicated their concerns about losing the rural nature of the road, Burke said. But he argues that DOT did not amend its plans based on the public comment.

Melrose disagrees.

In 1991 and again in 1995, Congress designated Route 1 part of a national highway system, he said, and with that came new standards. And two years ago, the Legislature directed DOT to modernize arterial highways in the state, including the 1.6-mile stretch of Route 1 in Warren. The project, at least this first phase, costs about $3.2 million.

What the road needed, Melrose said, was the addition of 8- to 10-foot-wide shoulders. Instead, DOT agreed to build a 6-foot shoulder with 2 feet more of grass designed to support the weight of a vehicle.

“We’ve deviated from the design standard significantly,” Melrose said.

The 11- to 12-foot-wide travel lanes will remain as they are, despite contrary claims made by opponents.

“We’re designing a 45 mph highway,” Melrose said. It is consistent with the current speed limit “and that’s how we’re posting it.”

He also emphasized that DOT will not straighten or flatten the route, as it often does in upgrades.

As work began this month, a tangible symbol of loss for the area emerged. Eighteen trees, some a century old, faced the business end of a chain saw. Artists began painting the scene to preserve it for posterity, and the planned acts of civil disobedience Monday called for protesters to sit in or be chained to the trees slated for removal.

“I do sympathize about the issue of the trees,” Melrose said. But in DOT parlance, the trees were “deadly fixed objects,” perilously close to the travel lanes.

Opponents argue that without trees and with paved shoulders, drivers will be emboldened to go faster.

Trees, they say, create an effect urban planners call “traffic calming.” And without a shoulder that allows people to pass a car stopped to make a left turn, drivers must proceed more cautiously.

Homeowner Sewall sees some of the protest rooted in what she calls “the powerlessness that we feel.”

Tim Sullivan, 33, of Rockport is a local activist and communication coordinator for the Green Independent party who joined the opponents, seeing a larger issue in the fight.

“My goal is to try to get DOT to think about alternatives,” he said. “I grew up in York County. Every major road there is just this ugly, wide road,” he said.

Sullivan was one of two arrested last Friday.

“If we don’t take a stand, we’re just going to get steamrolled into the pavement of Route 1,” he said.

Melrose said a moratorium has been declared on the second of four phases of the Warren-to-Thomaston reconstruction, and DOT will instead proceed to planned work on Route 1 between Camden village and Camden Hills State Park. Residents there, he noted, have not opposed the plans.