Summer Research Project Maps Every Tree on Campus
From left, the tree-mapping team on a 2025 project in nearby Michaux State Forest: Visiting Instructor in Environmental Studies Sarah Sterner and members of the class of 2026 Thea Duane, Cara Kamoie and Rachel Hoffman.
A summer of fieldwork gives Dickinson its first accurate tree census in 13 years—and a map anyone can carry
by Tony Moore
Visiting Instructor in Environmental Studies Sarah Sterner walked out onto the academic quad on a January morning with a 13-year-old map and one question: Are these trees still here?
Sterner was preparing a lab for ENST 162: Integrative Environmental Science, the introductory course for first-year students. The lab sends students out onto campus with the college's 2012 tree map, created by former Dickinson GIS specialist Jim Ciarrocca, to practice reading a map, locate a specific tree and measure its diameter at breast height. She wanted to be sure the assignment still worked.
"I didn't want students wandering around in the January chill for an hour looking for a tree that had been removed five years earlier," Sterner says. As it turned out, only 50 of the 67 trees recorded on the academic quad in 2012 were still standing, while others had been replaced with a different species and some GPS coordinates were slightly off target. "If only 75% of the map was accurate there, that's probably true for the rest of campus," Sterner says. Emerald ash borer had moved through the college's ash trees, hemlock woolly adelgid had hit the eastern hemlocks and construction had taken others.
So Sterner and a team of students counted them again—all of them.
Eight weeks, 10 miles a day
With funding from the Center for Sustainability Education's Sustainability Education Fund and the college's Research & Development Committee, Sterner hired three environmental studies interns for the summer 2025 research project: Thea Duane '26, Cara Kamoie '26 and Rachel Hoffman '26.
Over eight weeks, the three re-surveyed all 1,781 trees in the 2012 dataset, confirming each species and recording updated height and diameter. They logged the 454 trees that had come down since 2012 and added 338 that had been planted or missed the first time, tagging each new tree and fixing its GPS coordinates. The finished inventory covers roughly 215 species from 39 plant families. Current tree count: 1,665
It was walking work. Forestry hypsometers are used to collect tree height data and require the operator to stand at a minimum of 30 feet from the base of the tree with a clear line of sight to the highest branch. In an urban environment, buildings and surrounding trees can often obstruct that view, which led to the interns walking up to 10 miles each day to position themselves for tree measurements.
"It was a massive effort, and they did an incredible job," Sterner says, noting that the interns presented their findings at an Environmental Studies Earth Issues talk in November.
What 13 years of growth adds up to
The inventory also answered a question the college could not previously answer: what its trees are doing for the climate. As it turns out, 13 years of growth increased the lifetime carbon stored in Dickinson's campus trees by more than 3.5 million pounds of CO2.
"The tree-mapping project benefits the student researchers, but it also benefits the campus and the community by shaping how we manage our grounds, our tree canopy and our climate resilience planning," says Lindsey Lyons, executive director of CSE. "It's critical that we know what trees we have, as well as their health and diversity, so we can build the most resilient campus environment with the greatest potential for carbon sequestration."
Those numbers now have somewhere to go. The dataset is headed for environmental studies courses, where students can run their own carbon analyses instead of working from a textbook example.
A map you can walk with
Sterner spent this past summer turning the students' data into a new interactive map, built in ArcGIS and now open to the public. Visitors can pull it up on a phone, tap to navigate and click any tree they pass to see what it is and how big it has gotten.
The map is already doing more than orientation. The Trout Gallery worked with Sterner and her students to build a self-guided campus tree tour tied to the exhibition BRANCH: Trees in American Art, pairing living trees on campus with the ones hanging on the gallery walls. Maddy Hull '24, the gallery's post-baccalaureate fellow in museum education, did the research connecting the artwork to specific trees, and Claudia Colaprete '27 (art & art history, East Asian studies) contributed research and several of the photographs on the online tour.
Come January, students in ENST 162 will head out onto the quad with a map that matches what is actually standing there.
And future phases for the map include characterizing the trees on the Dickinson Farm as well as the solar array on Ritner Highway, while also developing an interactive map for facilities that will allow the college to track and update canopy changes in real time.
“Ultimately, I think that when we take the time to learn a tree’s name, it stops being part of the scenery and we become more invested in its future and well-being,” Sterner says. “My hope is that students using the Dickinson tree map will get to know the trees on their daily commute and in doing so will feel more connected to the natural world and more invested in its future.”
Anyone interested in getting involved with the ongoing campus tree inventory or who notices a change that isn't reflected is encouraged to contact Sterner.
TAKE THE NEXT STEPS
Published September 22, 2026