The Changing Flora of the Boston Harbor Islands Dale F. Levering, Jr. After more than three and one-half centuries of vicissitude, the deciduous forest that once covered the Boston Harbor islands may have begun to return Situated just to the north of the sandy, up- ing animals, the Eastern Deciduous Forest- lifted coastal plain of Cape Cod and just to the which was dominated by broad-leaved, south of the rocky coastline of northern New round-topped deciduous trees (as opposed to England, the Boston Harbor islands consti- needle-leaved, spire-topped evergreens)-was tute a unique maritime ecosystem. To the a richer source of food for the colonists than south of the Harbor, pines dominate the the evergreen forests to the north and south. sandy, mineral-deficient soil where the land No doubt this was one reason the English meets the sea; to the north, hemlock, white settled northward, rather than southward, pine, spruce, and fir. Some twenty thousand from Plymouth. years ago, when the Pleistocene ice sheet was The present-day vegetation of Moswe- at its maximum, the shoreline lay approxi- tusset Hummock, a small island situated at mately thirty miles east of where it does now; the northern end of Wollaston Beach in when the glacier first began to recede, what Quincy, is perhaps the closest indication we are now the Boston Harbor islands were ex- will ever have of what the Boston Harbor posed as high spots on what was then the islands’ vegetation looked like at the time of mainland. Alluvium from the Boston Basin English settlement. Remains of dead Ameri- deposited around the Boston Harbor islands can chestnut trees (Castanea americana) can by the Mystic, Charles, and Neponset rivers still be seen on Thompson’s Island, and young during this time created a mineral-rich sub- oak forest is reestablishing itself on Peddock’s stratum that plants would readily colonize Island. For the most part, however, the Boston after the glacier had melted away. Harbor islands have been cut over, and the In particular, the alluvium was colonized rich, climax deciduous forest that clothed by species of the Eastern Deciduous Forest, a them when the English arrived on these narrow, species-rich strip of forest stretching shores early in the seventeenth century is northeastward from the mountains of Ken- now in the early stages of biotic succession tucky and West Virginia, reaching the ocean from old fields to climax forest. along the Massachusetts shoreline between Ipswich and Plymouth. (It corresponds to The Islands’ Early History Zone 5 of the Arnold Arboretum’s cold-hardi- In 1585-thirty-five years before Plymouth ness map and to Zone 6 of the United States was settled-David Thompson established a Department of Agriculture’s map). Once trading post on the Boston Harbor island that dominated by chestnuts and oaks, it has been now bears his name. During summer of 16211 devastated by chestnut blight and by the Captain John Smith, who had landed at Ply- Europeans who settled in it, who have used it mouth in 1620, sailed into Boston Harbor. In as a source of construction timber and fire- the ship’s log he wrote of "the groves of trees, wood. With its complement of nut-consum- the fields of corn, and the well proportioned 19 Indians" standing on the shore. Captain livestock pasture. Smith and the crew set foot on the mainland By 1634 the English settlers had recognized at what is now Squaw Rock in the Squantum the value of the Boston Harbor islands as stra- section of Quincy. Although there has been tegic lookout points for protecting the devel- speculation that the corn fields he mentions opment of Boston and had begun to construct were in reality marsh grasses, fragmentary fortifications on Castle Island. Between 1850 remains of corn have been found in archaeo- and 1865, George’s Island was extensively Map of the Boston Harbor Islands in 1711. logical digs on Calf Island. Evidence of cleared altered by the construction of Fort Warren. areas suggesting gardens has also been docu- The world wars also significantly altered the mented. Once the settlers had cleared them of island ecosystem. Massive fortifications trees, the islands became valuable pasture were built on Peddock’s, Gallop’s, Lovell’s, land free of predators. Some of them-Sheep, Great Brewster, Middle Brewster, and Outer Calf, and Hog islands-reflect their use as Brewster islands. Until recent times, perhaps 20 as much as any use, the construction of forti- Emerald Necklace, planned to extend his fications has led to the destruction of the landscape through World’s End in Hingham, islands’ native plants and animals. into the Boston Harbor islands. Unfortu- As Boston grew into a prominent port and nately, Olmsted’s death brought to an end as urbanization spread, the islands’ value early realization of the special ecology of the became increasingly evident. (Sweetser’s his- Boston Harbor islands. Aerial view of the Boston Harbor islands, looking southeast toward Hull. Thompson Island is in the foreground, Spectacle Island at the left center margin. The bridge connects Moon Island (right center) with Long Island. The peninsula at the right rear is the northern part of the town of Hull. Copyright © 1988 by Alex S. MacLean/Landslides. tory of the Boston Harbor islands gives an The Boston Harbor Islands State Park early insight into their unique nature.) Because they were being used by the military, Frederick Law Olmsted, while creating the the Boston Harbors islands were largely off 21 limits to the general public for nearly two-thirds of the Boston Harbor Islands twentieth With the advent of nuclear century. weapons, State Park however, islands lying only a few miles off a coast lost much and the Commonwealth of of their strategic significance, , We want to create the best harbor ’ Massachusetts began acquiring the islands in Boston Harbor; park system in the world because it in 1974, the Boston Harbor Islands State Park was estab- has the potential to be just that. lished. Public visitation has been encouraged since then, and -Govemor Michael S. Dukakis, George’s Island, 1986 public campgrounds have been established on Lovell’s, and Peddock’s islands. service from Grape, Bumpkin, Ferry The Boston Harbor islands are a to Island makes it for Long Wharf, Boston, George’s possible remarkable resource, permitting people to take advantage of the free-of-charge water-taxi recreational and educational service provided by the Commonwealth from May until opportunities rarely found in an October to several of the Boston Harbor islands. Interpreta- urban setting. Though the Bos- ton skyline is rarely out of view, the islands have a wild character, providing a resting spot for mi- grating birds and city residents alike. People can camp on the islands or visit for the day, expe- riencing the forces of the sea and the wilds. Easily accessible via inexpensive ferry boats from Long Wharf, connected to each other by a free water taxi, the islands are destinations for resi- dents of every Boston neighbor- hood and the region, as well as tourists who venture out for pic- nics, school outings, and discov- ery. ’, Thirty-one islands are pres- ently owned by public agencies; seven are staffed during the sum- mer months as Boston Harbor State Park. The park is jointly Map of the Boston Harbor islands. Copyright © 1987 by The managed by the Metropolitan Christian Science Publishing Society. District Commission (MDC), which owns George’s, Lovell’s, and Peddock’s islands; and by the tion of the islands’ natural history and ecology is now pro- Department of Environmental which owns vided by island managers, who are coordinated through the Management, Massachusetts of Environmental Grape, Bumpkin, Gallop’s, Great Department Management Brewster islands and of the Volunteer service in and many (DEM). appreciation interpretation smaller islands. The City of Bos- of this state has been the Friends of unique park provided by i~ ton owns three islands which the Boston Harbor Islands. have yet to be included in the park: Long, Spectacle, and Rains- The Islands’ Plants ford islands. Each island in the The flora of the Boston Harbor islands reflects man’s impact park has its own history and its upon the landscape, and few undisturbed patches of native own present and potential uses- plants remain. The American Indians used to retreat to the in sum, the islands are a unique 22 resource of national-park qual- water-taxi hub and site of Fort sible by automobile, is the site of ity. Warren, a national Historic land- the Long Island Hospital and the The islands are drumlins (gla- mark-is by far the most heavily remnants of Fort Strong. Sum- cial hills) and rock outcroppings visited island, with its picnic mer work crews have begun to ranging in size from less than one grounds, concession stand, and clean up the island and it figures acre to over two hundred acres. running water. In recent years an prominently in the dreams of Seasonally occupied by Native intensive educational program many Boston environmentalists Americans, who harvested an has been developed on George’s and Harbor-lovers, though it is abundance of shellfish, the is- Island, providing programs to not in the park or open to the lands were used by Puritan colo- some 15,000 school children, public yet. Spectacle Island, a nists as wood lots and pasture including 2,000 Boston school former dump site, also remains lands. Over the years, the islands children, and to over 15,000 outside the park and is closed to were used for quarantine and summer visitors.