MILLINOCKET — A section of forest in an undeveloped area near Baxter State Park has been bought by the Nature Conservancy.

The organization announced Monday that it had purchased an additional 1,013 acres around Big Reed Pond, an area about 10 miles north of the park.

The land was bought from the Pingree family, which has owned the land for about 150 years.

The new purchase, three years after the conservancy bought 3,800 acres from the Pingrees, includes all the land surrounding a wilderness pond and the remaining unprotected watershed of Big Reed Pond.

Conservancy Director Mason Morfit said the $278,000 purchase completes the acquisition of the conservancy’s Big Reed Forest Preserve.

He said the organization now owns all the forest in the area that has not been disturbed by road construction or forest harvesting.

The area has been managed by Seven Islands Land Co. for many years and company records do not indicate that the land has ever been harvested. It is the largest such uncut forest known to exist in Maine.

Morfit said the group has spent more than $1 million in its two Big Reed Pond purchases and now plans to concentrate its efforts on preserving parts of the pine barrens of York County, which he said “are considered by many scientists to be the most threatened forest type in New England.”