One of Napa County's historic vineyards will remain agricultural forever.

Grape grower Andy Beckstoffer on Tuesday said that he is donating his 89-acre parcel of the original To Kalon vineyard in Oakville to the Land Trust of Napa County, reaping the benefits of a new law President Bush signed last week.

"It will always be agricultural land," said Beckstoffer about the vineyard first planted by H.W. Crabb in 1868.

"What (Crabb) started, we will finish," Beckstoffer told a group of reporters at his vineyard that borders Highway 29 at a press conference attended by Rep. Mike Thompson, D-St. Helena, and John Hoffnagle, executive director of the Land Trust of Napa County. Beckstoffer gives up the right to develop the property but will continue to farm the land.

Thompson, who spearheaded efforts to pass new tax deductions through Congress, believes the new rules will provide greater incentives to preserve agricultural lands.

"We lose two acres of agricultural land every minute across this country," Thompson said.

That's "bad" for agriculture, the environment and communities, he said.

"Whenever you have sprawl development, it costs local governments a lot more money to deliver services."

The tax incentives allow farmers who enter into conservation agreements to deduct up to 100 percent of their adjusted gross income for as many as 15 years. Farmers have 16 months to enter into the agreement under these rules. Until now the cap was 30 percent for six years.

The Oakville vineyard, known for its cabernet sauvignon grapes, is in an agricultural preserve under Measure J, the initiative Napa County voters passed in 1990. Under Measure J, lands in agricultural preserves cannot be developed without a vote of the people.

The agricultural preserves are not permanent because Measure J sunsets in 2020, explained Hoffnagle.

He now wants to preserve 1,000 acres of the Napa Valley every year and hopes the recently passed tax incentives will be extended.

Beckstoffer, 66, who has owned the 89 acres since 1994, campaigned for the bill and hopes others will donate their lands for conservation.

"It's good for business," he said, referring to the new tax rules.

About 20,000 acres of land in Napa County is in conservation agreements with the Land Trust of Napa County, though most of it is not prime agricultural land like the To Kalon vineyard.

Since 1976 the Land Trust has worked with more than 50 landowners in Napa County to preserve nearly 20,000 acres of land through conservation easements. Vineyards are planted on 9 percent of the valley's 500,000 acres -- or about 49,000 acres.

Beckstoffer's property may be the first property in the nation to be placed into a conservation agreement under the new rules, the speakers said.