ESSEX — - Murwin Johnson claps his hands and the ewes come running up a hill at the sheep farm he's lived on for five decades.

Sheep blats pierce the silence of this tranquil place, 50 acres of pasture and woods with vast views of the Connecticut River Valley.

A developer had his eye on the land recently, one of only three privately owned properties of 40 acres or more left in this 12-square-mile town of nearly 7,000 residents. His plan was to build 20 homes on the site.But there were the sheep to think about — and the local children. For years, boys and girls have visited the farm during summer sheep-shearing demonstrations and in the spring when the lambs are born.

So Johnson, 79, who used to work for the state Department of Agriculture, said no to the developer and the others with dreams of building "trophy homes" on one of the town's popular landmarks.

Instead, Johnson entered into an agreement with the local land trust to restrict the use of his land, a deal that local officials say is a milestone for Essex and the Essex Land Trust, the latest land trust to look to purchasing development rights as a way to preserve farmland.Town leaders are in favor of spending $150,000 of town funds to assist the land trust in acquiring the development rights to Johnson's Walnut Street property. Residents will vote on the $150,000 expenditure Wednesday.

First Selectman Phil Miller said that although the town and the land trust have worked together for years to preserve open space, this deal is the first time the town has been involved in the purchase of development rights for a local farm.

The purchase of development rights, a form of conservation easement or restriction, has been used by the state since the 1970s to preserve farmland and open space. But as the amount of farmland in the state shrinks, land trusts and municipalities are turning to acquiring development rights as a way to save what is left of the ever-dwindling number of farms in Connecticut.

As recently as last month, the town of Suffield purchased development rights to two local farms. Other towns that have looked to conservation easements to protect farmland include Pomfret, Ashford, Woodstock, Shelton, Simsbury, South Windsor, Ridgefield and Easton, said Jay Dippel of the state Department of Agriculture's farmland preservation division.

The state participates in deals involving farms that meet certain qualifications. Other agreements are made between towns and land trusts. Some municipalities buy the development rights outright and other easements are donated.

"What's new about this is that towns and local land trusts are using agricultural easements for the first time," said Henry Talmage, executive director of the Connecticut Farmland Trust, a private statewide land trust. "These easements are unique because the farmer can still farm on the land and maintain it, but he no longer has the development rights to it. And regardless of how many times the property is sold, the restriction lives on."

Johnson's farm has long been on the radar of Essex officials and local preservationists who feared losing the land to development. The farm was identified in a 2005 town conservation and development plan as a property that should be preserved.

"He has a wonderful farm and he's done a lot of work there," said Dippel, whose department did not take part in the deal but had visited the farm. "He's got his sweat and blood and life there and it's important for him to preserve it. It's wonderful that Essex is working to preserve the few farms remaining there."

But the negotiations have not been easy. Some say the talks lasted five years. Others say 10. William Grover, president of the nonprofit Essex Land Trust, called the deal "the toughest challenge that we've faced yet as a land trust." The 40-year-old group has holdings of more than 400 acres.

Talmage said rural towns struggling to make their budgets and looking to preserve farmland often lack the resources needed to acquire the land.

"When these deals get pulled off, it really is a time for celebration," Talmage said.

Towns looking for remedies often turn to regional and local land trusts. Dippel said Connecticut has more than 100 land trusts, the highest number in the nation.

"Towns are starting to plan more," Dippel said. "It's not about preserving everything at any cost. It's about planning for their services and where they have their support systems. There's more and more thought about it on a local level."

Preserving Johnson's farm would add to open space acreage in Essex, which Miller said amounts to a little over 12 percent. He said reaching the state open space preservation goal of 20 percent for each municipality by 2023 is "ambitious," particularly without state forest or water company land to look to. The town is already looking at preserving two other farms in town, totaling about 120 acres, he said.

Under the agreement, the land trust would pay Johnson the market value of the development rights of the farm, which have been appraised at $780,000. Johnson also would receive tax breaks on the property, which is appraised at more than $1 million, according to minutes from a recent town meeting.

The land trust would have right of first refusal to buy the farm if the Johnsons decide to sell the land.

The total cost of the development rights is estimated at $850,000, which includes legal fees and other expenses.

Though some have complained that the Johnson farm deal would keep the land private, those who support using the $150,000 say keeping the land as farm land or open space would spare Essex the extra burden they say more residences would likely bring to the town's services, schools and roadways.

"Towns are now taking a look at it from a fiscal point of view. They don't want to build that new $90 million middle school," Talmage said.

And the growing interest in locally grown food has also prompted townsto take another look at their farms as a viable food source for the community.

"There is this kind of awakening in the towns, largely driven by the local food movement," Talmage said. "There's a whole new group of people interested in farmland preservation that have never been at the table before."

To help raise money for purchase, Johnson deeded 6 acres in the southern area of his property to the Essex Land Trust, which plans to sell the property as two building lots.

Johnson said he isn't worried about those lots intruding on his sanctuary, where the only regular noise comes from the faint whistle of the distant Essex Steam Train. These days, as Johnson tends his acres and sheep, he stops often to reflect on the land's beauty with his wife, Polly, as they sit on a bench underneath two shade trees.

"I just wanted this to be around for the next generation of kids," Johnson said.