Researchers date demolished New Paltz house using tree ring data

Jaimie Kaefer doing research.

For her senior research project, Jaimie Kaefer, a December 2019 graduate of the SUNY New Paltz Environmental Geochemical Science program, used wood samples from a recently demolished house adjacent to the Wallkill Valley Rail Trail between Rosendale and Kingston to determine the age of the structure.

Kaefer’s research advisor was Dr. John Rayburn, an associate professor in the Geology Department at SUNY New Paltz who specializes in climate records from sediment cores and tree rings. Jeffery Benjamin, a Ph.D. candidate from Columbia University, had collected the wood samples from the house.

But Kaefer had a problem: she needed a nearby mature Eastern Hemlock stand to build a data set. And since the onset of the invasive Wooly Adelgid in the early 2000s, finding mature hemlocks would be challenging. However, Cara Gentry, the coordinator of land stewardship for the Wallkill Valley Land Trust (WVLT), knew exactly where one could be found.


“Cara had recently conducted an annual site visit to the WVLT conservation easement known as Hare East where she found a beautiful, mature stand of Eastern Hemlocks and had made a mental note of the hemlock stand because the Eastern Hemlocks are under attack by a small aphid-like insect called the invasive Wooly Adelgid,” said Christie DeBoer, executive director of the WVLT. “She thought it was impressive to see a stand of hemlocks with so many trees still alive.”

The Hare East conservation easement covers two properties, one owned by the original easement grantors, Rob Hare and Iza Tripani-Hare and another which is now owned by Jon and Denine Sherman. After a few emails and a phone call, Kaefer and Rayburn were allowed to take tree core samples from the hemlock trees.

The SUNY New Paltz researchers were able to create a “complete tree ring record” that spanned from the Fall of 1530 to the Spring of 2019, and then determined that the house was built in 1867.

In a research article, Kaefer said the tree ring data showed that “several of the Hemlocks begin life in the 1750s – 1770s, so perhaps the canopy was opening due to early settlement logging in the area. The trees then demonstrated a normal growth pattern until the 1820s – 1840s when again there is an increased growth rate.”

Kaefer noted that this corresponds “roughly to the onset of industrialization such as the cement industry activity in the area and may again be the result of canopy opening due to increased logging.” She wrote that the living trees at the sample site also “show a significantly higher growth rate suggesting generally more favorable growing conditions at this location until about 1920 when their growth rates increased likely due to active land management.” The data also showed the impact of the pesky Wooly Adelgid around 2003.

 “Research such as this not only reveals insights about the region’s ecological history, but also underpins why protection of open space is vital to understanding how habitats evolve as well as the impact of humans on the environment,” DeBoer said.

 To review the entire article by Kaefer, visit the Wallkill Valley Land Trust’s website “Latest News” page: