The Trustees of Reservations’ Grassland Restoration project at Ward Reservation has recently come to near-full fruition. According to ecologist Russell Hopping, “The main work is done, but we will be in a restoration phase for many years to bring back the habitat.”
It was in 2010 that The Trustees commenced the restoration of the property’s natural habitat. They began by clearing wooded areas on Boston Hill, and have since moved on to Holt Hill, a drumlin that hosts a community of fire-adapted plants. Over the years, successional forest had displaced native plant and wildlife species, thereby disrupting the entire ecosystem. The smothering out of sunlight meant the forest understory was more favorable for invasive species than for natives. “We really wanted to bring back that habitat that was more open and fire dependent,” explains Hopping.
There are a multitude of rare plants, animals, and insects that depend on that environment. The frosted elfin butterfly, for example, which feeds exclusively on wild indigo—a wildflower species whose numbers had dwindled under the dark canopy. “We wanted to benefit that species in addition to others,” says Hopping. To do so, they cleared roughly nine acres out of the center of the hill connecting two smaller openings, which they had been maintaining for their scenic value—that was step one.
Next, they cleared 15 acres of young woodland that had once been all pasture, as indicated by the many low stone walls. Hopping refers to “the connectivity of habitat,” when describing the once-wide-open area. “Over the decades, it grew back in but we had about 40 acres of fields that were fragmented, meaning that there were patches of forest in between. That really limited the value of the fields as habitat,” he explains. Standing by an area that, until recently, was filled with 40- to 50-foot-high mid-successional forest, Hopping explains that it made sense to make the fields larger and “defragment” them. “There’s really not a lot of habitat like this around, especially on a hillside.”
Many of the species that depend on grassland habitat need an expansive area to thrive, preferably in excess of 20 acres. “The bigger you get, the more likely it is you will have a greater diversity of species and more viable populations.” The bobolink is one such species. They are more common in prairie states, but because prairie lands have been so negatively impacted by today’s agricultural practices, they are actually doing better in the Northeast. “New England has taken on more of an importance for this species,” says Hopping.
After the second phase of clearing, they returned to Boston Hill and cleared 12 more acres, which is likely the last large-scale clearing they will do. The most recent clearing was of three and a half acres that had been planted with white pines, red pines, and Norway maples (an invasive species) by Mrs. Ward back in the mid-1920s. The planting was starting to decline; the understory was almost all Norway maple saplings, the red pines were dying off, and winter storms were felling trees. “We could see where this was going,” says Hopping. “It had outlived its life, so to speak. We viewed it as an opportunity.”
Today, about 25 reservation acres are open grasslands. Trees remain in some areas but “it is more of a savannah,” as Hopping describes it. It is to the meadows they hope to attract bluebirds, tree swallows, and grassland birds like killdeers—an “indicator” species. “It was great to see all the killdeers and baby chicks running around last year,” says property manager Adam Rolffs. “You know the habitat is working. That’s what we wanted.”
The stewards aren’t targeting specific species; they are looking for those that indicate that what they have created is big enough and of the right structure. They would love to draw American kestrels, also known as sparrow hawks, our region’s smallest falcon, which has declined dramatically in Massachusetts. They eat grasshoppers, dragonflies, and meadow voles—all those species survive in the habitat The Trustees has reestablished. So far, they have sighted one pair of kestrels. Hopefully others will follow. They’d also be happy to see Eastern meadowlarks and a large suite of butterfly species. Though, Hopping says, “We’d be thrilled with any wildlife and plants that like this open habitat.”
“What’s fascinating,” he notes, “is that we didn’t replant. We had a pretty good idea that, once we removed the trees and the sunlight got down to the ground, all the seeds in the seed bank would germinate—and that’s exactly what happened.” Goldenrods, asters, and violets are among the species now flourishing. “There’s a whole smorgasbord of wildflowers out there,” says Hopping. “They were just waiting for that disturbance and sunlight.”
They have also set up about 40 paired bluebird boxes for nesting. Many of the bird species on the reservation are territorial. By providing two boxes near to each other, they are less likely to fight over them, thereby reducing mortality. If that kind of management is not in place, tree swallows and bluebirds are often found dead in the boxes. During last year’s harsh winter, bluebirds essentially starved to death sitting atop piles of Asian bittersweet—an invasive plant species that they tried feeding on, but it took more energy to digest the non-native than it gave them. “Invasives are keeping these birds here all winter now.” Yet another reason to restore native plant habitats.
Hopping notes: “The big story is that, in both cases, here and over at Boston Hill, we have been very careful about looking at what is here in terms of the history, the plants, and the animals—what already exists and what can we do, as stewards of the land, to capitalize on that. We are looking to restore some uncommon and rare habitats while at the same time making it very accessible to the public to come experience, recreate, and learn about the area.”
“A lot of people don’t even know this is here, they can’t tell what it is from the road,” adds Rolffs, noting that when the clearing first got underway, people expressed concern until they understood what was being done, at which point they became supporters of the project. Prior to the clearings, visitors would head to the quaking bog or to the solstice stones, where there’s a clear view of Boston. Now, there are two large expanses from which to see the city skyline. “These areas are actually places that visitors are seeking out as a destination now,” says Hopping. “They love the openness and being able to see over the entire expanse and the city way in the distance.”
“It’s nice when things line up,” he concludes. “The value we are looking for [in terms of] habitat is complementary to recreation and to the scenic values and vice versa. This is one of those bright spots where there is no conflict. Everybody is a winner, including the wildlife.”