Adding another gem to its emerald necklace of properties on Chappaquiddick, the Martha’s Vineyard Land Bank announced this week that it has purchased 22 acres of native sandplain off Quammox Road. The property includes 550 feet of beachfront on the extreme eastern end of Katama Bay.

The sellers are Dick and Laura Chasin, who own about 95 acres in the same area including the old Barnes estate. The purchase price is $2.1 million, with $1.85 million coming from the land bank and $250,000 coming from the Chappaquiddick Open Space Fund. The south-facing property slopes gently down to the bay and includes a small salt pond braced against the barrier beach. Much of the vegetation is pristine sandplain habitat, a low-growing dense groundcover of blueberry, bayberry, lichens and native grasses, salt-blasted and dotted with hardy wildflowers from spring until fall.

A preliminary plant inventory on the property has documented, among other things, yellow thistle, bristly foxtail, toothed whitetop aster, butterfly weed, a variety of goldenrods and asters, sand jointweed, oxeye daisy, lady’s tresses, American germander, groundsel tree and high tide bush. Farther back on the property is an oak and pitch pine woodland.

The closing was Dec. 26.

“This is a really good price and the land bank is extremely grateful to both the Chasins and to the open space fund,” said land bank executive director James Lengyel this week. Formed several years ago by a small group of Chappaquiddick residents, the open space fund has quietly and steadily raised money to assist with strategic open space purchases on the small island that remains one of the last rural outposts in the town of Edgartown.

“It is such a remarkable committee that has been so helpful to the land bank so many times. If other neighborhoods on the Vineyard had a fund like this it would help the land bank go into these neighborhoods and preserve open space,” Mr. Lengyel said.

Situated at the Wasque end of Litchfield Road at the intersection known as Five Corners (where there is another land bank property by the same name), Quammox Road is a town right of way that runs down to the bay. Some Chappy residents use it as an access point to launch small sailboats, kayaks and rowboats. The area is remote and tranquil and the view across the bay was once to the outer barrier beach that connected Chappaquiddick to Edgartown. But since the breach at Norton Point nearly two years ago, the view has changed dramatically and now is a distinct vista of the frothy Atlantic Ocean pouring through the breach, which has grown to nearly a mile in width.

The property will be named the Quammox Preserve. Mr. Lengyel said he anticipates it will be open to the public by the coming summer. The land bank has been negotiating actively with the Chasins for two years to buy the land, but Mr. Lengyel said the first letter of interest in the property actually went out in 1988.

“Quammox Preserve fits the pattern which the land bank has often seen; sometimes these things take decades. This is an example of sometimes how long it takes the land bank to achieve its goals,” he said.

The Quammox Preserve purchase brings the total land bank holdings on Chappaquiddick to 506 acres.