The Martha’s Vineyard Museum is close to selling the West Tisbury land once envisioned as its future home to the neighbors, the Polly Hill Arboretum and the Martha’s Vineyard Agricultural Society.

The sale is likely to be completed by the end of the week, arboretum executive director Tim Boland said. Surveying work was underway and everything was going very positively, he said.

“We both could see real utilitarian needs [for the land] ... and we feel strongly about keeping it in the agrarian spirit,” Mr. Boland said of the unified purchase with the agricultural society.

The nearly 10-acre parcel has been on the market for $1 million, but the museum’s executive director, David Nathans, said late last week it was not actively being marketed at the moment due to an offer pending for what he believed was a fair price.

Nothing has been formalized, but the first steps had been taken, Mr. Nathans said.

“They are two very seasoned and credible organizations,” he said. “They have been great neighbors.”

In 2002 the arboretum, agricultural society and the museum, which was then the Martha’s Vineyard Historical Society, worked together to buy a 25-acre parcel off State Road from the Littlefield family.

The land, tucked between the arboretum and the fairgrounds, was known as Scarecrow Farm because of the intricate scarecrows the late Margaret Littlefield staked through the rows of her vegetable garden, long after it had been grazed by sheep as part of the family’s larger holdings — some of which had been sold for the arboretum and wildlife refuges through the years.

When the sale was announced in 2002, property trustee Leah Littlefield said the family had searched for a way to transfer ownership to a nonprofit organization that would be of service to the Island.

In that $2.5 million sale, the museum put forward $1 million for its nearly 10 acres, with the arboretum acquiring 10 acres next to its existing State Road property and the agricultural society adding five acres to its holdings.

The arboretum was able to use that land for a maintenance building, housing for an employee, a fenced-in nursery and a production greenhouse, Mr. Boland said. Likewise there was an open field that matches the square field on the other side of State Road. “I call it a decompression stretch,” Mr. Boland said, noting that part of the attraction of the new purchase was to maintain visible open space along that stretch of road.

The arboretum has no plan to develop the land now under negotiation. It was more a buffer among its northern wall, he said, and it would help the arboretum if they were to do any further expansion in the future.

“The ag society needs more land than we do,” he said, and the details of how the land would be divided were still unsettled.

“At Polly Hill, we’re thrilled we are able to do this because of what it means to the community, the town, the whole Island,” Mr. Boland said.

Back when the large parcel was first acquired, the historical society set forth on a $25 million plan to build a new home for keeping and exhibiting the artifacts and documents it had been collecting since its formation in 1923. The campaign suffered from the financial crisis, competing large capital projects on the Island, leadership changes and changes of heart among its board members. In 2007 the organization was carrying an operating deficit and by 2009 the capital campaign was put on hold.

The museum is presently located in Edgartown, in a campus patched together from a few Edgartown houses; the oldest dating back to the 1740s was once the home of Edgartown customs agent Thomas Cooke.

The board considered and rejected a move to the old Edgartown School.

Late last year the museum began to explore the possibility of retrofitting the former Marine Hospital in Vineyard Haven for its new home.

In June, using funds provided by a private individual, the museum signed a purchase and sale agreement with the St. Pierre family, which owns the 4.5 acre parcel half a mile from downtown Vineyard Haven. The site had been listed at $3.19 million for about a year, but the sale price was not disclosed.

Mr. Nathans has said of the potential sale of the West Tisbury land, “Every step is a great step,” toward the new facility. “I’m pleased that our change might mean an opportunity for [the arboretum and ag society]. Things seem to be falling into place. The [purchase and sale agreement] on the St. Pierre Marine Hospital was one; this is another.”