In 2019, the Nantucket Conservation Foundation’s (NCF) Board of Trustees decided to retire cranberry cultivation on the Foundation’s Windswept Bog property (located on Polpis Road) to pursue a watershed level wetland restoration project. The 231-acre Windswept Bog property, which is contiguous with several thousand acres of protected conservation land in the Middle and Eastern Moors, contains 39 acres of former cranberry bog and 111 acres of natural wetlands. Cranberry cultivation began at Windswept in the early 1900’s, with the Foundation purchasing the property in 1980.
Since this decision, NCF’s Science and Stewardship Department has been working with staff from the Massachusetts Division of Ecological Restoration (DER) to develop restoration plans for the former bogs and surrounding areas at Windswept. Through its Cranberry Bog Program, DER works with local, state, and federal partners to provide technical services (such as engineering, design work, permitting and construction assistance), small grants, and project management and fundraising help to landowners interested in restoring wetlands on retired cranberry bogs.
Over the last few years and with support from DER, our science team has been busy gaining a better understanding of the rare and unique resources that are already present on this property so that we can incorporate this information into our wetland restoration plans. Working with Dr. Jen Karberg (our wetland ecologist), the USDA Natural Resources Conservation Service (NRCS) conducted a ground penetrating radar (GPR) survey across portions of the former bogs to document historic peat layers, indicating the presence of wetlands at the site prior to cranberry bog construction. Danielle O’Dell (our wildlife ecologist) oversaw three seasons of spotted turtle trapping and radio-tracking to determine pre-restoration habitat use patterns. This information will be used to minimize impacts to this species during the construction process as well as ensure that suitable habitat will be created post-restoration. Libby Buck (our ecological research technician) spent two seasons monitoring wetland bird habitat use so that we can gain a better understanding of how this shifts and changes over time in response to restoration. Kelly Omand (our botanist) thoroughly documented the upland, wetland, rare and invasive plant species present at the site to target for future management or protection.
We are very excited to now be at the stage where all this information collected over the past several years is being incorporated into more refined plans for implementing the actual restoration work. DER, which has already been through this process at numerous other restored cranberry farms in southeastern Massachusetts, has been a fantastic partner on this project. With their expertise and financial assistance, we are working with Fuss and O’Neill, Inc. (an environmental engineering firm) over the coming year to advance our existing 25% preliminary design plans to 50% preliminary design plans, perform a hydrologic investigation incorporating data downloaded from multiple surface and ground water loggers across the property, apply for the first stage of project permitting under the Massachusetts Environmental Protection Act (MEPA), and develop several “landscape renderings” of what the completed project could look like for use in outreach and education. If this work proceeds as planned, we could have preliminary permitting completed (or at least in progress) by 2023, which would be followed by final permitting and anticipated construction initiation over the next year (dependent on grant funding availability).
Karen Beattie (our department director) and Jen Karberg recently spent a day in the field with Jess Cohn (Ecological Restoration Specialist with DER) visiting a number of potential wetland “reference sites” on Nantucket for this restoration process. These reference sites are areas of comparable size, structure, and function to what Windswept Bog likely supported before it was altered by cranberry farming. For Windswept Bog, we plan to use a natural reference wetland on Nantucket as a model for our restoration work as well as a means of measuring project success. Although more reconnaissance is needed, we located a very promising site near Windswept Bog that likely has similar soils, hydrology, glacial history, and other environmental conditions.
Finally, we just recently consulted with the Nantucket Conservation Commission regarding plans to install 6 (50 x 50 ft) research treatment plots within one of the bog cells slated for restoration. Through this pilot project, we plan to test several different restoration techniques that have never been implemented in a cranberry bog restoration project. The traditional restoration technique for breaking up the bog’s dense sand layers (resulting from many years of past cranberry cultivation) has been to use an excavator to “scoop and flip” the compacted sand layer, exposing the underlying peat to facilitate restoration. At sites elsewhere in southeastern Massachusetts, this has been effective but is very time consuming and expensive to implement.
We plan to test disk harrowing, plowing and a combination of these treatments to see if we can achieve similar results using simpler, more time efficient and less costly techniques. In conjunction with this work, we will be collecting data on vegetation response, disturbance depth, soil moisture, and bulk density. These test treatments will be completed in March 2022 using equipment that NCF and Nick Larrabee (our cranberry bog manager) already own. We will be monitoring the response over the 2022 growing season and incorporating promising results into our overall restoration plans for the site.
We are extremely grateful to our partners at DER for technical expertise and funding provided to support this project since its inception. We look forward to sharing more information and progress regarding this project as plans continue to move forward!
The Nantucket Conservation Foundation is a private, non-profit land trust that depends on contributions from our members to support our science projects, conservation property acquisitions and land management efforts. If you are not already a member, please join us now! www.nantucketconservation.org