Two years after the city of Bothell began preserving the remnants of what is optimistically called “Bothell’s last great forest,’’ another parcel of land has been added, moving the city closer to having 64 acres of natural habitat close to downtown.

A total of 41 acres has now been acquired, becoming a conservation legacy for generations to come, say members of the fundraising groups. Some $1.8 million still needs to be raised for additional acreage.

The most recent acquisition, 5.9 acres, was bought from Tom and Jeanie Robinson, who acquired the site several years ago to protect it from being developed and sold it to the city for $250,000, a reduced cost. The Bothell City Council approved the sale last month.

At one point, 50 houses were planned in the area, said Patricia Parkhurst, recreation and park planning manager, said. But the steep hillside there prevented additional development.

“It’s quite an accomplishment to achieve the acquisition,’’ Parkhurst said.

There are three more parcels the city would like to acquire in North Creek Forest, she said.

Funding to purchase the property came through a grant from King County Conservation Futures funds and the Washington State Recreation and Conservation Office, which administered the federal Land and Water Conservation Fund. The city worked in collaboration with two community groups, the Friends of the North Creek Forest and Help Our Woods, to apply for funding.

Bothell’s “urban forest,’’ consists of mature coniferous forest with large Douglas fir, Western Hemlock and cedar trees, and is home to a wide array of plants and animals, including pileated woodpeckers and band-tailed pigeons, Parkhurst said. The forest is an integral part of the North Creek watershed, which filters water flowing into North Creek, an active salmon stream.

The purchases secure a nearly unbroken wildlife corridor from Juanita Bay in Kenmore to Bothell, protecting a portion of the 33-square-mile North Creek Watershed at a time when already 49 percent of it is covered with impervious surfaces such as parking lots, buildings and roads.

Nancy Bartley: nbartley@seattletimes.com or 206-464-8522