By Kyrnan Harvey
I was able to attend a meeting of the Three Village Community Trust last Thursday that addressed the complicated issue of nonnative invasive plants. Guest speaker Luke Gervase of the Long Island Invasive Species Management Area led the discussion that emphasized Patriots Hollow State Forest, the few dozen acres of woods running north and west of Route 25A in Setauket, roughly opposite Stop & Shop. Recently the trust announced that it is working toward a stewardship agreement with the New York State Department of Environmental Conservation, as reported in these pages, to restore the woods, currently impenetrable with fallen and cracked trees and the bittersweet, greenbriar and multiflora rose that have seized the day.
But this is not a virgin forest. English settlers in the 17th century farmed along North Country Road and what would become 25A, and the Setalcotts likely did the same before that.
The Fitzsimmons family started farming there in 1939, growing potatoes, and in ensuing years acquired parcels and rented the land to other farmers. Meanwhile, the Roman Catholic Diocese of Rockville Center owned 30 acres along 25A since the 1960s, which was tilled as late as 1980. In other words, this was more or less open land until the farming was discontinued.
Immediately thereafter began the ecological succession of plants that start germinating in fallow fields. On Long Island these would have first been sun-loving perennials like asters, grasses, boneset (Eupatorium perfoliatum), goldenrods and milkweeds, but also sun-loving woody plants like eastern red cedar, Virginia creeper, poison ivy, Rosa multiflora, sumacs (Rhus spp.), wild raspberries and blackberries (Rubus spp.). Native trees like gray birch and black cherry and exotics, like white mulberry and black locust, soon start displacing the pioneering species.
Desirable successional tree species would be hardwood natives like oaks, sassafras and black gum (Nyssa sylvatica), but 40 years later at Patriots Hollow we have, in this prime location within the Old Setauket Historic District, a vast mess of nonnative invasives like black locust, tree of heaven (Ailanthus) and Norway maple that out-competed other canopy trees like the native red maple, the caterpillar-hosting black cherry and the dignified white oak and have precluded the prosperity of understory natives like shadbush (Amelanchier), arrowwood (Viburnum dentatum), spicebush and American holly, not to mention the potential of an array of wonderful undergrowth perennials.
Restoring Patriots Hollow Forest to a multifunctional habitat (for birds and insects, as well as for human use with trails) by engineering species diversity through vertical layering (canopy trees, understory trees and shrubs, undergrowth perennials) and horizontal layering (woods, edge of woods, open clearing) is a daunting project. It requires a vision, human and financial resources and a coherent set of attainable goals. Cynthia Barnes, president of the board of trustees for the Three Village Community Trust, says that a task force will be meeting to draft some preliminary guidelines and ideas for restoration of this DEC property, including doing an inventory of the flora and fauna and describing the current conditions. The task force will work on hosting facilitated public planning workshops in collaboration with the DEC later this year.
Which brings me back to our speaker, Gervase of the LIISMA, who made the point that it is advised to only gradually remove nonnative invasives, else you are clearing the way for a new wave of opportunistic invasive. For example, if you cut down all the black locusts, then you will quickly get a vast inundation of fast-growing Norway maples. But this presumes there will be little or no maintenance at the site. Thousands of freshly germinated maple seedlings can annually be quickly rubbed out with a scuffle hoe, if there is an integrated management plan in place.
Nor need a rigidly dogmatic approach be adopted. Perhaps some black locusts should be left, ones that have attained to the gnarly character of old age, considering that they are “near native”; that it is not prohibitively difficult to establish understory trees, shrubs and perennials under them and that their wood is for split-rail fencing.
I advocate for a nuanced approach that would be capable of adapting to shifting circumstances and that would be capable of improvising wise decisions midstream.
Kyrnan Harvey is a horticulturist and garden designer residing in East Setauket. For more information, visit www.boskygarden.com.