Beeches on the Island
American beech is a dominant species within the coastal oak-beech forest community.2 In 1639, Lion Gardiner reported large “…oaks intermixed with walnut and beech”3 on nearby Gardiners Island, which likely describes what Winthrop would have encountered on Fishers Island as well.
This is confirmed by a 1734 lease agreement between the lessor Winthrops and George and Mary Havens stipulating that the Winthrops had full rights over the woods on the island, and that the lessees were forbidden to cut or suffer to be cut or strip, peel or destroy any Vines, Pines, Spruce, Cedar, Wallnutt, Chestnutt, Birch, Beach, Maple, Sassafras, Ash or Elm or any Cherry trees…4
Despite Winthrop’s early edict, land use practices have nearly eliminated beeches on Fishers Island. Just five groves have survived – three on Land Trust property – although more may still be identified. While the groves on Land Trust property are protected, they remain vulnerable to disease and a changing climate.5
Beech Leaf Disease
I had been watching for signs of beech leaf disease (BLD) ever since attending an online lecture in 2020. Last May, looking upwards towards the beech tree leaves silhouetted against the sky, I spotted an abnormal gallery of shadowy bands within the leaves – a tell-tale sign of the disease.
First recognized in Ohio in 2012, by 2019 both American and European beech trees in the areas around New York City, western Connecticut, and Long Island, including Suffolk County, were showing the symptoms of BLD.6
Since this disease is a relatively recent discovery,7 much about it, including mode of transmission, pathology, and cure, remains unknown. But understanding and combating the disease has become a priority for forest managers, plant disease researchers, and other scientists, since beech trees are critically important for providing food and habitat that sustains a wide range of wildlife.
American Beech: Thin Skin, Shallow Roots, Long Life8
The American beech, Fagus grandiflora, is a storied species that can live to 400 years. One 365-year-old tree in eastern Tennessee was inscribed by Daniel Boone, “D. Boon cilled a bar in year 1760”. Its girth (circumference) was 28½ feet when it fell in 1916.”9
Although the smooth, grey veneer of bark is perfect for memorializing oneself with incised initials, this is a selfish act that triggers a cycle of imitators. It scars the tree for life at best. At worst, it could make the tree more vulnerable to infection from diseases like beech bark disease (BBD), a devastating insect-initiated fungal infection.
Growth, Form and Age
Unlike the more upright, straight-trunk beech trees typical of coastal oak-beech forests found in other Fishers Island groves, most beeches growing at the Betty Matthiessen Wildlife Sanctuary on Island Pond are stunted, with contorted branches emanating from lower on the trunk. This form is more typical of trees of the rare maritime beech plant community, which is influenced by oceanic forces, such as hurricane strength winds and salt spray.10
Counting annular rings is the only reliable way to measure a tree’s age. A large branch, broken from an old beech tree at Island Pond last fall, showed 116 annular growth rings, which indicate the branch formed around 1905 and the tree a little earlier. This grove likely became established as farming practices were coming to an end in this area.
A healthy beech grove creates a canopy of shade and fallen leaves which form a brown, spongy, persistent blanket that inhibits the establishment of other competitive species. Beech saplings are often found in clumps growing out of the roots of the older trees. Otherwise, there is little understory.
The notable exception is the twig-like parasitic plant known as “beechdrop,” Epifagus virginiana.
Epifagus lives exclusively on the roots of American beech trees. Beechdrop is an annual plant that lacks leaves and chlorophyll, relying on energy derived from the roots of older trees. While beechdrops are technically parasites, they cause no harm to their host trees; indeed, the presence of Epifagus indicates a high quality, undisturbed plant community.11
Although all five of the Fishers Island groves inhabit the same soil class, only one has an abundant population of beechdrops and three groves have none.