Wooster earth sciences team coauthors climate research on tree rings published in scholarly journal

Earth Sciences faculty, staff, and students at The College of Wooster recently published “Changing climate response of Northeast Ohio white oaks, USA: Is it tree age or site age?” in the June 2025 issue of Dendrochronologia, a peer-reviewed international scholarly journal. The article encompassed the work of three Applied Methods and Research Experience (AMRE) teams, collaboration with local partners, and funding from the National Science Foundation (NSF).

The Wooster team of coauthors included Gregory C. Wiles, Shoolroy Chair of Natural Resources and professor of earth sciences, Meagen Pollock, Lewis M. and Marian Senter Nixon Professorship in the Natural Sciences, Nick Wisenberg, lab technician in Scovel Hall, Melita Wiles ’22, Caitlyn Denes ’23, Tyrell Cooper ’25, and Desiree Smith ’25.

“This region is getting warmer and wetter overall, especially in the spring,” said Pollock. “The team studied how white oak trees respond to summer weather by looking at forest stands of different ages.” In spring 2022, an AMRE team consisting of Cooper, Smith, and others worked under the leadership of Pollock and Wiles, with peer advising from Denes, an environmental geoscience graduate. They studied tree rings from 100, 200, and 300+ year old white oaks in and around Wooster. The white oak provides reliable, yearly ring growth, so the team analyzed the cores from these different generations of trees to understand how they are responding to the increase in precipitation (a several-inch rise annually throughout the past 100 years).

Pollock said, “Understanding how tree age and site history affect how oaks respond to climate can help scientists monitor forest health, estimate how much carbon forests can store, and improve how researchers use tree rings to study past climates.” In summer 2023 and 2024, the research team continued to accomplish significant fieldwork, data management, and produced a brochure and a functional database for the public. Wiesenberg directed the field and lab work and Melita Wiles, a physics and math major, worked on one of the tree-ring sites and helped with data analysis and statistics. Their finished publication showcases analysis results from the tree-ring sites.

“This opportunity was very important to me because it wiped away any doubts and preconceptions that I had about doing research and being a scientist,” said Cooper, an environmental geoscience major. “This was my first time working effectively and intensely with a team of fellow students to create a product to be used by individuals outside of the classroom. I am very proud of the work we put in and happy I got the chance to contribute to a publication as an undergrad.”

Lab Technician Nick Wiesenberg and Des Smith ’25 work in the field alongside other AMRE students in year two of the project.

According to Pollock, younger stands consistently grow better when there’s more rain in June and July. However, tree growth across all sites tends to decline with higher summer temperatures, and usually, when it’s hotter, there’s less rainfall. The combination of rising temperatures and a prediction of less rain in late summer could mean more stress on white oak trees in the future.

“The data in this study are contributed to an International Tree-Ring Data Bank, which is widely used by others,” said Wiles, adding that future employers and graduate advisors of these students like to see what products/deliverables came from research. Along with their contributions to the data bank, Cooper and Smith won an outstanding poster award for presenting their work at the American Geophysical Union conference in December 2022. “I am amazed at the ability of our students to present so articulately and with such confidence, and this award, in part, reflects this, said Wiles.”

Smith, an environmental geoscience and archaeology major, said the award and positive experience at AGU was meaningful because, “This was the first ‘real research’ I’d done, it was my first conference, and it was on an international level. In my time at Wooster, I’ve continued to share my research and attended four total conferences and developed a love for public communication and accessible science.”

The research was funded by two NSF grants: A GEOPAths (Pathways into the Earth, Ocean, Polar and Atmospheric & Geospace Sciences) grant helps to broaden participation in the geosciences through experiential learning for students from underrepresented communities, and an earth sciences grant that seeks to better understand hydroclimate in the Midwest.

Wiles emphasized that the group’s work was conducted in collaboration with several local sites, including Secrest Arboretum (Ohio State University), Wooster Memorial Park (Friends of WMP and City of Wooster), the College campus, Kinney Fields and Cornerstone Elementary (City of Wooster), David Kline’s Farm (author and farmer), Browns Lake (The Nature Conservancy), and Johnson Woods (Ohio Department of Natural Resources).  “These are all stands of trees that are preserved and maintained by many groups and individuals, and without their efforts this work would not be possible,” noted Wiles.

Coauthors Wiles, Pollock, Smith, and Cooper participated in an invertebrate field survey with other AMRE students and members of Trout Unlimited.

Featured image: Tyrell Cooper ’25 collects a tree-ring sample in spring 2022. 

Posted in Experiential Learning, Homepage Featured, News on May 13, 2025.