One of the many features that make visiting the Landis Arboretum a unique experience is its old growth forests. This article from the Winter 2002 newsletter, originally written by Director Fred Breglia with Dave Yarrow, has been edited for brevity. At that time the large Old Growth Forest area in the northern section was not part of the Arboretum. It makes reference to the Arboretum’s signature Great Oak, which was toppled by a hurricane in 2011 – after 400 years!
A new survey team has been formed to explore and evaluate potential old growth forests in the Hudson-Mohawk Valley, Schoharie Valley, and Catskills. Its headquarters are based at the Landis Arboretum, and led by arborist Fred Breglia and naturalist Dave Yarrow.
On Sunday, December 2, the Eastern New York Old Growth Survey Team searched for ancient trees in the 20 acres on the hill above the Farmhouse, west of the Great Oak. The team concluded that although there is significant old growth on the site, it has been disturbed and damaged in the 200-year history of European settlement. However, enough original and ancient trees remain to be regenerating an exemplary old growth forest. That forest consists of approximately 30% hemlock, 20% red oak, and 10% white oak, with most trees in the 250 – 300 year range. The Arboretum’s Great Oak was estimated to be 400 years old, the oldest tree on the Arboretum’s grounds. However, the team discovered an old stump in the 500-year old range. Other species that reached old growth status include black birch, basswood, sugar maple, beech, big tooth aspen, and ironwood. Other sites investigated by the Old Growth Survey Team include the Lisha Kill and the Albany Pine Bush, both owned by the Nature Conservancy, and Old Maid’s Woods, which is owned by the City of Schenectady.
According to forest botanists and ecologists, old growth is defined by 10 characteristics that describe the trees, understory, and terrain. One key criterion is that at least six large trees per acre must be at least 150 years old. Trees must be of a variety of all age ranges, from young saplings to mature trees. The forest must have a well-developed canopy, with a significant number of snags, downed trees, and woody debris. There should be an understory of small trees, shrubs, herbs, mosses, and lichens, all of which indicates a rich biodiversity of flora and fauna. Human disturbances should be absent or minimal.
When Columbus arrived in the Western Hemisphere, America east of the Mississippi was sheltered by a thick cover of tall, majestic trees – an ancient forest of grand dimensions that had existed for uncounted centuries. European settlers quickly cut down the trees to clear the land, converting it into farmland and harvesting the trees for timber, charcoal, and potash. In the 21st Century, only a tiny remnant of that virgin forest – less than 0.25% – survives. Many acres have regrown with secondary stands that can only approximate the once great forests. Most of these forest remnants and secondary growth are in national and state forest preserves; smaller tracts are owned by environmental organizations, private citizens, and timber companies.
Old growth forests are valuable for many reasons, such as they provide habitat for a maximum diversity of life, including many endangered and threatened species. Because of their biological complexity and maturity, ancient forests serve as critical controls in scientific studies of forest dynamics. Studies also demonstrate old growth forests are efficient systems in removing carbon from the atmosphere, mitigating global climate change due to greenhouse gases.
Remember: “If you’re not forest, then you’re against us.”