Keystone Trees

American Chestnut & Atlantic White Cedar

Long Island’s geological history resulted in a range of conditions and a diversity of habitats. Deciduous trees thrived in the rich soils of the glacial moraines, while a vast network of maritime forests grew on lowlands among the island’s network of coastal streams . These habitats featured two of Long Island’s iconic trees – American Chestnut and Atlantic White Cedar.

American Chestnut

The American chestnut was once a common tree in the forests of the Eastern United States; it ranged from Georgia to Maine and from the Mississippi to the Atlantic, including parts of Long Island. In the heart of its range, on the slopes of the Appalachian Mountains, it  was a dominant tree species, growing over 100 feet tall and earning its moniker as the “Redwood of the East”.  But an Asian chestnut tree imported into New York in the late 1800s carried a fungus that would change everything. While the fungus only sickened Asian chestnuts, it was fatal to their American cousins. The “Chestnut Blight” as it came to be known, was first noticed in the Bronx Botanical Garden in 1904. Within fifty years, it spread across the American chestnut’s entire range, killing as many as 4 billion trees and nearly driving the tree into extinction. But the saga isn’t over yet. Almost since the blight started, scientists have kept the species on life support, while feverishly working to figure out a way to beat the blight. The effort, led by the American Chestnut Foundation (ACF), includes work to foster natural resistance, extensive crossbreeding, even genetic bioengineering. 

Since 2003, Seatuck has worked to maintain the genetic viability of Long Island’s remaining American Chestnuts. We identify and pollinate existing trees, trying to coax out a few viable nuts before the blight catches up to them. The nuts are then planted and young saplings watched until they are mature enough to flower, bear nuts and start the cycle over again. The goal is to keep this native “Long Island stock” going until the scientists come up with a solution to the blight.

Think you’ve found an American Chestnut?

Have you found a tree on Long Island that you think might be an American Chestnut? The first step is to use this identification guide from the American Chestnut Foundation to make sure it’s not another chestnut species or a hybrid (it can be hard to tell sometimes!). If you still think it’s an American Chestnut, please let us know – you can give us a call at 631-581-6908 or email us at [email protected]. We’ll make plans to visit the tree with you or put you in touch with our partners who represent the American Chestnut Foundation on Long Island.

Atlantic White Cedar

Atlantic White Cedar (Chamaecyparis thyoides) was once a common evergreen tree that was widespread across Long Island. It was found along most, if not all, of the streams on the south shore, selected areas inland and along the north shore. The species was common to abundant in the Pine Barrens where today, the largest extant populations remain, and in several locations on the South Fork. A large stand once occurred on Plum Island although it appears to not have existed on the North Fork. 

With the exception of one other population located in the lower Hudson River Valley, the species total distribution in New York State is restricted to Long Island. And throughout its larger range Atlantic White Cedar generally lives up to its name, never growing far from the Atlantic Coast (the inland most population  is only 90 miles from the ocean). 

Today, the distribution of White Cedar on Long Island is much reduced, due to harvesting and habitat loss and modification including changes to hydrologic conditions to the wetlands in which it grows.  It has been extirpated throughout the western portions of its original range. Three small populations remain in Nassau County and one of these three, in East Massapequa, will likely disappear in the near future due to habitat loss. One tree remains in Babylon and two small populations occur in Islip.  A viable stand occurs in western Suffolk County within the southern portion of Blydenburgh County Park in Smithtown. Several large viable stands are found in Sagaponack and North Sea, on the South Fork. As mentioned above, the stronghold for the species is in a few wetlands situated in the eastern part of the Pine Barrens. The two largest stands are at Cranberry Bog County Nature Preserve where thousands of trees, of various ages, occur and in the Flanders area including Sears-Bellows County Park. A unique “dwarf” cedar population may occur here but more research is needed to determine whether this population is truly dwarfed. 
 Due  to the quality of the wood, highly resistant to decay from fungus and insects, Atlantic White Cedar was, and still is, highly prized. The wood is used to make cedar shakes, used in decoy making and boat building, and due to the typically arrow-straight nature of the main trunk, used for masts and posts of various kinds. This straight-arrow quality also was the primary reason it was used for water supply piping in colonial New York, in which logs were bored out and butt end to butt end sealed with pitch and resin.
Seatuck's John Turner and Emily Hall pose with some Suffolk County AWCs

White Cedar is distinctive from other evergreen trees native to Long Island. It has distinctive flattened branches with minute leaves that often form flat sided “sprays”. The cones are small, the size of a pea. The smooth bark is often slightly spiraled, a feature best seen on larger trees.  

Seatuck’s work to conserve Atlantic White Cedars
Seatuck is working with partners to restore this iconic and important wetland tree to Long Island. We are currently assessing sites suitable for reintroduction, i.e. locations where it was known from but is no longer and where conditions are still conducive to the survival of planted trees which include a high water table and rich organic soils.  

Related Information

Surveys & Consulting

Good conservation begins with good science. A thorough understanding of both historical and existing ecological conditions is essential to ensuring that decisions regarding conservation policy initiatives and land management are effective and successful.

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Water Reuse

March 2023 – Seatuck releases WATER REUSE ROADMAP & ACTION PLAN. Seeks to advance water reuse as a strategy to address water quality and water quantity issues across Long Island.

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