At a Nantucket cranberry bog, conservation group launches its biggest restoration project

Excavation work began last month to restore a 40-acre Nantucket cranberry bog to naturally functioning wetlands.

The project at Windswept Bog, off Polpis Road, is the largest-ever restoration conducted by the Nantucket Conservation Foundation. It seeks to “unwind” human intervention on approximately 40 acres of bog, said Karen Beattie, vice president of science and stewardship.

The nonprofit foundation has been focused on land acquisition for 60 years, she said. Now that it owns some 9,000 acres of land — about a third of the island — the foundation wants to add more restoration to its agenda.

“Our strategic priorities are still acquisition, but we're also looking to put a lot more focus on doing ecological restoration work, such as this, on the property that we already own,” she said.

Nantucket Conservation Foundation

On Wednesday, the Windswept Bog project received a fresh infusion of public grant money: $1 million from the U.S. Fish and Wildlife Service, toward a total cost of about $3.4 million.

This winter, workers are excavating artificially deposited sand from the bog and using it to fill the drainage ditches. The center of the bog will be lowered and the land regraded to give it a more natural contour.

Nantucket Conservation Foundation

“I suspect that most of the restored wetlands will be vegetated,” she said. “At first it'll be grasses, and sedges, and rushes, and things like that. And then over time, you'll start to see some wetland shrubs, such as highbush blueberry and sweet pepperbush start to move in.”

Work will stop in mid March until next winter to protect wildlife who use the bog in the warmer months. The foundation’s goal is to finish the project next winter.

“It's been a really great learning experience for us,” Beattie said. “And I think we'll be doing a lot more of this kind of work in the future.”

The foundation owns the Windswept Bog and retired the bog from cranberry growing several years ago. Natural peat beneath the bog shows it was a wetland prior to human intervention, she said.

Foundation staff continue to cultivate about 25 acres of berries at the Milestone Bog, which the foundation also owns.

The cranberry industry in southeastern Massachusetts has faced economic challenges for a number of reasons, including cranberries from Canada flooding the market, along with climate change, Beattie said. She said warmer temperatures affect the berries and bring an increase in fungus and new insects.